3.1\u521b\u5efa\u6570\u636e\u5e93<\/h3>\n\n\n\n CREATE DATABASE library_db
CHARACTER SET utf8mb4;
USE library_db;<\/pre>\n\n\n\n3.2\u521b\u5efa\u6570\u636e\u5e93\u8868<\/h3>\n\n\n\n CREATE TABLE book(
bno CHAR(10) PRIMARY KEY,
bname VARCHAR(50) NOT NULL,
author VARCHAR(30),
press VARCHAR(30),
pubyear INT,
stock INT DEFAULT 1 CHECK(stock>=0)
);
CREATE TABLE reader(
rno CHAR(12) PRIMARY KEY,
rname VARCHAR(20) NOT NULL,
rsex CHAR(1)
CHECK(rsex IN('\u7537','\u5973')),
dept VARCHAR(40),
phone VARCHAR(20)
);
CREATE TABLE borrow(
borrowid INT AUTO_INCREMENT PRIMARY KEY,
rno CHAR(12) NOT NULL,
bno CHAR(10) NOT NULL,
borrowdate DATE NOT NULL,
returndate DATE NOT NULL,
actualdate DATE,
CONSTRAINT fk_reader
FOREIGN KEY(rno)
REFERENCES reader(rno)
ON DELETE RESTRICT
ON UPDATE CASCADE,
CONSTRAINT fk_book
FOREIGN KEY(bno)
REFERENCES book(bno)
ON DELETE RESTRICT
ON UPDATE CASCADE
);
desc book;
desc reader;
desc borrow;<\/pre>\n\n\n\n![\"image-20260531161032406\"\/](\"data:image\/svg+xml;base64,PCEtLUFyZ29uTG9hZGluZy0tPgo8c3ZnIHdpZHRoPSIxIiBoZWlnaHQ9IjEiIHhtbG5zPSJodHRwOi8vd3d3LnczLm9yZy8yMDAwL3N2ZyIgc3Ryb2tlPSIjZmZmZmZmMDAiPjxnPjwvZz4KPC9zdmc+\")
<\/div><\/figure>\n\n\n\n<\/div><\/figure>\n\n\n\n<\/div><\/figure>\n\n\n\n<\/div><\/figure>\n\n\n\n3.3 \u6dfb\u52a0\u4fee\u6539\u5220\u9664\u5b57\u6bb5<\/h3>\n\n\n\n ALTER TABLE book
ADD pages INT;
\u200b
ALTER TABLE reader
ADD email VARCHAR(50) UNIQUE;
\u200b
\u9a8c\u8bc1\uff1a
desc book
desc reader
\u200b
ALTER TABLE book
MODIFY author VARCHAR(50);
\u200b
ALTER TABLE reader
MODIFY phone VARCHAR(20)
DEFAULT '\u65e0';
\u200b
SHOW CREATE TABLE borrow;
ALTER TABLE book
DROP COLUMN pages;
\u200b
ALTER TABLE borrow
DROP FOREIGN KEY fk_reader;<\/pre>\n\n\n\n4.\u6570\u636e\u63d2\u5165<\/h2>\n\n\n\n INSERT INTO book VALUES
('B001','\u6570\u636e\u5e93\u7cfb\u7edf\u6982\u8bba','\u738b\u73ca',
'\u9ad8\u7b49\u6559\u80b2\u51fa\u7248\u793e',2018,5),
\u200b
('B002','C\u7a0b\u5e8f\u8bbe\u8ba1\u8bed\u8a00','K&R',
'\u673a\u68b0\u5de5\u4e1a\u51fa\u7248\u793e',2015,3),
\u200b
('B003','\u4e09\u4f53','\u5218\u6148\u6b23',
'\u91cd\u5e86\u51fa\u7248\u793e',2010,8),
\u200b
('B004','\u8ba1\u7b97\u673a\u7f51\u7edc','\u8c22\u5e0c\u4ec1',
'\u7535\u5b50\u5de5\u4e1a\u51fa\u7248\u793e',2018,4);
\u200b
INSERT INTO reader
VALUES
('R2024001','\u5f20\u660e','\u7537',
'\u8ba1\u7b97\u673a\u5b66\u9662','13812345678',
'zhangming@qq.com'),
\u200b
('R2024002','\u674e\u82b3','\u5973',
'\u4fe1\u606f\u5b66\u9662','13912345678',
'lifang@qq.com'),
\u200b
('R2024003','\u738b\u78ca','\u7537',
'\u6587\u5b66\u9662','13612345678',
'wanglei@qq.com');
\u200b
INSERT INTO borrow VALUES
(1,'R2024001','B001',
'2025-03-01',
'2025-03-15',
'2025-03-14'),
(2,'R2024001','B003',
'2025-03-10',
'2025-03-24',
NULL),
(3,'R2024002','B002',
'2025-04-01',
'2025-04-15',
NULL),
(4,'R2024003','B004',
'2025-03-20',
'2025-04-03',
'2025-04-05');<\/pre>\n\n\n\n4.1 \u8bbe\u8ba1\u8fdd\u53cd\u5916\u952e\u7ea6\u675f\u548ccheck\u7ea6\u675f\u5e76\u89e3\u91ca<\/h3>\n\n\n\n INSERT INTO borrow(
rno,bno,
borrowdate,
returndate)
VALUES(
'R999999',
'B001',
'2025-05-01',
'2025-05-15');
\u200b
\u9519\u8bef\uff1aCannot add or update a child row:
a foreign key constraint fails
\u200b
\u539f\u56e0\uff1aR999999\u5728reader\u8868\u4e2d\u4e0d\u5b58\u5728\uff0c
\u8fdd\u53cd\u53c2\u7167\u5b8c\u6574\u6027\u7ea6\u675f\u3002
\u200b
\u8fdd\u53cdcheck
INSERT INTO reader
VALUES(
'R2024004',
'\u8d75\u654f',
'\u672a\u77e5',
'\u827a\u672f\u5b66\u9662',
'13712345678');
\u200b
\u9519\u8bef\uff1aCheck constraint violated
\u200b
\u539f\u56e0\uff1arsex\u5b57\u6bb5\u53ea\u80fd\u53d6
\u7537 \u6216 \u5973\uff0c
\u56e0\u6b64\u8fdd\u53cdCHECK\u7ea6\u675f\u3002<\/pre>\n\n\n\n5.\u6570\u636e\u67e5\u8be2\uff08DQL-\u57fa\u7840\u67e5\u8be2\uff09<\/h2>\n\n\n\n 1.select\u67e5\u8be2\u5168\u90e8\u56fe\u4e66\u4fe1\u606f
select * from book;
2.\u67e5\u8be2\u5e93\u5b58\u5927\u4e8e3\u7684\u56fe\u4e66
SELECT bno,bname,stock
FROM book
WHERE stock > 3;
3.\u67e5\u8be22018\u5e74\u51fa\u7248\u4e14\u5e93\u5b58\u4e0d\u5c11\u4e8e4\u672c\u7684\u56fe\u4e66
SELECT bno,bname,pubyear,stock
FROM book
WHERE pubyear = 2018 AND stock >= 4;
4.\u67e5\u8be22015\u5e74\u81f32018\u5e74\u51fa\u7248\u7684\u56fe\u4e66
SELECT bno,bname,pubyear
FROM book
WHERE pubyear BETWEEN 2015 AND 2018;
5.\u67e5\u8be2\u51fa\u7248\u793e\u4e3a\u201c\u91cd\u5e86\u51fa\u7248\u793e\u201d\u6216\u201c\u9ad8\u7b49\u6559\u80b2\u51fa\u7248\u793e\u201d\u7684\u56fe\u4e66
SELECT bno,bname,press
FROM book
WHERE press IN('\u91cd\u5e86\u51fa\u7248\u793e','\u9ad8\u7b49\u6559\u80b2\u51fa\u7248\u793e');
6.\u67e5\u8be2\u4e66\u540d\u4e2d\u5305\u542b\u201c\u8ba1\u7b97\u673a\u201d\u7684\u56fe\u4e66
SELECT bno,bname
FROM book
WHERE bname LIKE '%\u8ba1\u7b97\u673a%';
7.\u67e5\u8be2\u5c1a\u672a\u5f52\u8fd8\u7684\u501f\u9605\u8bb0\u5f55
SELECT *
FROM borrow
WHERE actualdate IS NULL;
8.\u6309\u5e93\u5b58\u6570\u91cf\u964d\u5e8f\u67e5\u8be2\u56fe\u4e66
SELECT bno,bname,stock
FROM book
ORDER BY stock DESC;
9.\u67e5\u8be2\u5e93\u5b58\u6700\u591a\u7684\u524d2\u672c\u56fe\u4e66
SELECT bno,bname,stock
FROM book
ORDER BY stock DESC
LIMIT 2;
10.\u67e5\u8be2\u6240\u6709\u4e0d\u540c\u7684\u51fa\u7248\u793e
SELECT DISTINCT press
FROM book;<\/pre>\n\n\n\n6.\u6570\u636e\u66f4\u65b0\uff08update\/delete\uff09<\/h2>\n\n\n\n 1.\u5c06BOO1\u7684\u5e93\u5b58\u4fee\u6539\u4e3a6
UPDATE book
SET stock = 6
WHERE bno = 'B001';
\u200b
SELECT * FROM book WHERE bno='B001';
2.\u4fee\u6539\u5f20\u660e\u7684\u9662\u7cfb\u548c\u7535\u8bdd
UPDATE reader
SET dept = '\u4eba\u5de5\u667a\u80fd\u5b66\u9662',
phone = '18888888888'
WHERE rno = 'R2024001';
\u200b
SELECT * FROM reader WHERE rno='R2024001';
3.\u5c062018\u5e74\u51fa\u7248\u56fe\u4e66\u5e93\u5b58\u7edf\u4e00\u589e\u52a01
UPDATE book
SET stock = stock + 1
WHERE pubyear = 2018;
\u200b
SELECT * FROM book WHERE pubyear=2018;
4.\u5220\u9664\u4e00\u4e2a\u6d4b\u8bd5\u8bfb\u8005
INSERT INTO reader
VALUES('R2024999','\u6d4b\u8bd5\u8bfb\u8005','\u7537','\u6d4b\u8bd5\u5b66\u9662','\u65e0');
\u200b
DELETE FROM reader
WHERE rno = 'R2024999';
5.\u4e8b\u52a1\u63a7\u5236\uff1a\u66f4\u65b0\u540e\u56de\u6eda
START TRANSACTION;
\u200b
UPDATE book
SET stock = stock - 1
WHERE bno = 'B003';
\u200b
SELECT * FROM book WHERE bno='B003';
\u200b
ROLLBACK;
\u200b
SELECT * FROM book WHERE bno='B003';<\/pre>\n\n\n\n7.\u805a\u5408\u67e5\u8be2\u4e0e\u5206\u7ec4\u7edf\u8ba1<\/h2>\n\n\n\n 1.\u7edf\u8ba1\u56fe\u4e66\u603b\u6570
select count(*) as \u56fe\u4e66\u603b\u6570 from book;
2.\u7edf\u8ba1\u56fe\u4e66\u5e93\u5b58\u603b\u91cf
select sum(stock) as \u5e93\u5b58\u603b\u91cf from book;
3.\u7edf\u8ba1\u5e73\u5747\u5e93\u5b58
select avg(stock) as \u5e73\u5747\u5e93\u5b58 from book;
4.\u67e5\u8be2\u6700\u5927\u5e93\u5b58\u548c\u6700\u5c0f\u5e93\u5b58
SELECT MAX(stock) AS \u6700\u5927\u5e93\u5b58,
MIN(stock) AS \u6700\u5c0f\u5e93\u5b58
FROM book;
5.\u6309\u51fa\u7248\u793e\u7edf\u8ba1\u56fe\u4e66\u6570\u91cf\uff0c\u5e76\u7b5b\u9009\u6570\u91cf\u5927\u4e8e\u7b49\u4e8e1\u7684\u51fa\u7248\u793e
SELECT press, COUNT(*) AS \u56fe\u4e66\u6570\u91cf
FROM book
GROUP BY press
HAVING COUNT(*) >= 1;<\/pre>\n\n\n\n8.\u591a\u8868\u8fde\u63a5\u67e5\u8be2<\/h2>\n\n\n\n1.\u7b49\u503c\u8fde\u63a5\uff1a\u67e5\u8be2\u8bfb\u8005\u59d3\u540d\u548c\u6240\u501f\u56fe\u4e66
SELECT reader.rname, book.bname
FROM reader, borrow, book
WHERE reader.rno = borrow.rno
AND borrow.bno = book.bno;
2.\u5185\u8fde\u63a5\uff1a\u67e5\u8be2\u501f\u9605\u8bb0\u5f55\u8be6\u60c5
SELECT r.rname, b.bname, br.borrowdate, br.returndate
FROM borrow br
JOIN reader r ON br.rno = r.rno
JOIN book b ON br.bno = b.bno;
3.\u5de6\u5916\u8fde\u63a5\uff1a\u67e5\u8be2\u6240\u6709\u8bfb\u8005\u53ca\u5176\u501f\u9605\u8bb0\u5f55
SELECT r.rno, r.rname, br.borrowid, br.bno
FROM reader r
LEFT JOIN borrow br
ON r.rno = br.rno;
4.\u53f3\u5916\u8fde\u63a5\uff1a\u67e5\u8be2\u6240\u6709\u501f\u9605\u8bb0\u5f55\u53ca\u8bfb\u8005\u4fe1\u606f
SELECT r.rname, br.borrowid, br.bno
FROM reader r
RIGHT JOIN borrow br
ON r.rno = br.rno;
5.\u81ea\u8eab\u8fde\u63a5\uff1a\u67e5\u8be2\u540c\u4e00\u5e74\u51fa\u7248\u7684\u4e0d\u540c\u56fe\u4e66
SELECT a.bname AS \u56fe\u4e661,
b.bname AS \u56fe\u4e662,
a.pubyear AS \u51fa\u7248\u5e74\u4efd
FROM book a
JOIN book b
ON a.pubyear = b.pubyear
AND a.bno < b.bno;<\/pre>\n\n\n\n9.\u5d4c\u5957\u67e5\u8be2<\/h2>\n\n\n\n1.IN\uff1a\u67e5\u8be2\u501f\u8fc7\u4e66\u7684\u8bfb\u8005
SELECT *
FROM reader
WHERE rno IN(
SELECT rno FROM borrow
);
2.\u6bd4\u8f83\u8fd0\u7b97\u7b26\uff1a\u67e5\u8be2\u5e93\u5b58\u5927\u4e8e\u5e73\u5747\u5e93\u5b58\u7684\u56fe\u4e66
SELECT bno,bname,stock
FROM book
WHERE stock > (
SELECT AVG(stock)
FROM book
);
3.EXISTS\uff1a\u67e5\u8be2\u5b58\u5728\u501f\u9605\u8bb0\u5f55\u7684\u8bfb\u8005
SELECT *
FROM reader r
WHERE EXISTS(
SELECT *
FROM borrow br
WHERE br.rno = r.rno
);
4.ANY\uff1a\u67e5\u8be2\u5e93\u5b58\u5927\u4e8e\u4efb\u610f\u4e00\u672c2018\u5e74\u51fa\u7248\u56fe\u4e66\u5e93\u5b58\u7684\u56fe\u4e66
SELECT bno,bname,stock
FROM book
WHERE stock > ANY(
SELECT stock
FROM book
WHERE pubyear = 2018
);
5.ALL\uff1a\u67e5\u8be2\u5e93\u5b58\u4e0d\u5c11\u4e8e\u6240\u6709\u56fe\u4e66\u5e93\u5b58\u7684\u56fe\u4e66
SELECT bno,bname,stock
FROM book
WHERE stock >= ALL(
SELECT stock
FROM book
);<\/pre>\n\n\n\n10.\u96c6\u5408\u67e5\u8be2<\/h2>\n\n\n\n1.UNION\uff1a\u5408\u5e76\u8bfb\u8005\u59d3\u540d\u548c\u4f5c\u8005\u59d3\u540d\u5e76\u53bb\u91cd
SELECT rname AS name
FROM reader
UNION
SELECT author AS name
FROM book;
2.UNION ALL\uff1a\u5408\u5e76\u8bfb\u8005\u59d3\u540d\u548c\u4f5c\u8005\u59d3\u540d\uff0c\u4e0d\u53bb\u91cd
SELECT rname AS name
FROM reader
UNION ALL
SELECT author AS name
FROM book;
3.\u6a21\u62df INTERSECT\uff1a\u67e5\u8be2\u501f\u8fc7\u4e66\u7684\u8bfb\u8005\u8bc1\u53f7
SELECT rno
FROM reader
WHERE rno IN(
SELECT rno
FROM borrow
);
4.\u6a21\u62df EXCEPT\uff1a\u67e5\u8be2\u6ca1\u6709\u501f\u4e66\u7684\u8bfb\u8005
SELECT rno,rname
FROM reader
WHERE rno NOT IN(
SELECT rno
FROM borrow
);<\/pre>\n\n\n\n11.\u89c6\u56fe\u64cd\u4f5c<\/h2>\n\n\n\n1.\u521b\u5efa\u672a\u5f52\u8fd8\u56fe\u4e66\u89c6\u56fe
CREATE VIEW v_unreturned AS
SELECT br.borrowid, r.rname, b.bname,
br.borrowdate, br.returndate
FROM borrow br
JOIN reader r ON br.rno = r.rno
JOIN book b ON br.bno = b.bno
WHERE br.actualdate IS NULL;
2.\u67e5\u8be2\u89c6\u56fe
SELECT * FROM v_unreturned;
3.\u521b\u5efa\u5b66\u751f\u8bfb\u8005\u89c6\u56fe\uff0c\u5e26 WITH CHECK OPTION
CREATE VIEW v_student_reader AS
SELECT *
FROM reader
WHERE dept LIKE '%\u5b66\u9662%'
WITH CHECK OPTION;
4.\u6d4b\u8bd5\u53ef\u66f4\u65b0\u89c6\u56fe
UPDATE v_student_reader
SET phone = '18800000000'
WHERE rno = 'R2024002';
\u8bf4\u660e\uff1a
\u8be5\u89c6\u56fe\u57fa\u4e8e\u5355\u8868 reader \u521b\u5efa\uff0c\u6ca1\u6709\u805a\u5408\u51fd\u6570\u3001\u5206\u7ec4\u548c\u8fde\u63a5\uff0c\u56e0\u6b64\u5c5e\u4e8e\u53ef\u66f4\u65b0\u89c6\u56fe\u3002
5.\u521b\u5efa\u4e0d\u53ef\u66f4\u65b0\u7684\u805a\u5408\u89c6\u56fe
CREATE VIEW v_press_count AS
SELECT press, COUNT(*) AS total
FROM book
GROUP BY press;
\u8bf4\u660e\uff1a
\u8be5\u89c6\u56fe\u4f7f\u7528\u4e86 GROUP BY \u548c COUNT \u805a\u5408\u51fd\u6570\uff0c\u56e0\u6b64\u4e00\u822c\u4e0d\u80fd\u76f4\u63a5\u66f4\u65b0\u3002
6.\u5220\u9664\u89c6\u56fe
DROP VIEW v_unreturned;
DROP VIEW v_student_reader;
DROP VIEW v_press_count;<\/pre>\n\n\n\n12.\u7d22\u5f15<\/h2>\n\n\n\n1.\u521b\u5efa\u666e\u901a\u7d22\u5f15
CREATE INDEX idx_book_bname
ON book(bname);
2.\u521b\u5efa\u552f\u4e00\u7d22\u5f15
CREATE UNIQUE INDEX idx_reader_phone
ON reader(phone);
3.\u521b\u5efa\u590d\u5408\u7d22\u5f15
CREATE INDEX idx_borrow_rno_bno
ON borrow(rno,bno);
\u67e5\u770b\u7d22\u5f15
SHOW INDEX FROM book;
SHOW INDEX FROM reader;
SHOW INDEX FROM borrow;
\u5220\u9664\u7d22\u5f15
DROP INDEX idx_book_bname ON book;
DROP INDEX idx_reader_phone ON reader;
DROP INDEX idx_borrow_rno_bno ON borrow;<\/pre>\n\n\n\n13.\u6570\u636e\u5b8c\u6574\u6027\u7ea6\u675f\u9a8c\u8bc1\u4e0e\u7ea7\u8054\u64cd\u4f5c<\/h2>\n\n\n\n1.\u5b9e\u4f53\u5b8c\u6574\u6027\u9a8c\u8bc1\uff1a\u4e3b\u952e\u4e0d\u80fd\u4e3a\u7a7a
INSERT INTO book(bno,bname,author,press,pubyear,stock)
VALUES(NULL,'\u6d4b\u8bd5\u4e66','\u6d4b\u8bd5\u4f5c\u8005','\u6d4b\u8bd5\u51fa\u7248\u793e',2020,1);
\u8bf4\u660e\uff1a
bno \u662f book \u8868\u4e3b\u952e\uff0c\u4e3b\u952e\u4e0d\u80fd\u4e3a\u7a7a\uff0c\u56e0\u6b64\u63d2\u5165\u5931\u8d25\u3002
2.\u53c2\u7167\u5b8c\u6574\u6027\u9a8c\u8bc1\uff1a\u63d2\u5165\u4e0d\u5b58\u5728\u7684\u56fe\u4e66\u7f16\u53f7
INSERT INTO borrow(rno,bno,borrowdate,returndate,actualdate)
VALUES('R2024001','B999','2025-05-01','2025-05-15',NULL);
\u8bf4\u660e\uff1a
B999 \u5728 book \u8868\u4e2d\u4e0d\u5b58\u5728\uff0cborrow.bno \u662f\u5916\u952e\uff0c\u56e0\u6b64\u8fdd\u53cd\u53c2\u7167\u5b8c\u6574\u6027\u3002
3.\u7528\u6237\u5b9a\u4e49\u5b8c\u6574\u6027\u9a8c\u8bc1\uff1a\u5e93\u5b58\u4e0d\u80fd\u5c0f\u4e8e0
UPDATE book
SET stock = -1
WHERE bno = 'B001';
\u8bf4\u660e\uff1a
stock \u5b57\u6bb5\u8bbe\u7f6e\u4e86 CHECK(stock>=0)\uff0c\u5e93\u5b58\u4e0d\u80fd\u4e3a\u8d1f\u6570\u3002
4.\u7528\u6237\u5b9a\u4e49\u5b8c\u6574\u6027\u9a8c\u8bc1\uff1a\u5e93\u5b58\u4e0d\u80fd\u5c0f\u4e8e0
UPDATE book
SET stock = -1
WHERE bno = 'B001';
\u8bf4\u660e\uff1a
stock \u5b57\u6bb5\u8bbe\u7f6e\u4e86 CHECK(stock>=0)\uff0c\u5e93\u5b58\u4e0d\u80fd\u4e3a\u8d1f\u6570\u3002
5.ON UPDATE CASCADE \u6d4b\u8bd5
UPDATE reader
SET rno = 'R2024999'
WHERE rno = 'R2024003';
SELECT * FROM borrow
WHERE rno = 'R2024999';
\u8bf4\u660e\uff1a
reader.rno \u66f4\u65b0\u540e\uff0cborrow \u8868\u4e2d\u5bf9\u5e94\u7684\u5916\u952e rno \u4f1a\u81ea\u52a8\u540c\u6b65\u66f4\u65b0\u3002<\/pre>\n\n\n\n14.\u89e6\u53d1\u5668<\/h2>\n\n\n\n\u51c6\u5907\uff1a\u5220\u9664\u65e7\u89e6\u53d1\u5668
DROP TRIGGER IF EXISTS trg_borrow_before_insert;
DROP TRIGGER IF EXISTS trg_return_after_update;
DROP TRIGGER IF EXISTS trg_reader_before_delete;
\u521b\u5efa\u5220\u9664\u8bfb\u8005\u65e5\u5fd7\u8868
CREATE TABLE reader_delete_log(
logid INT AUTO_INCREMENT PRIMARY KEY,
rno CHAR(12),
rname VARCHAR(20),
dept VARCHAR(40),
delete_time DATETIME DEFAULT CURRENT_TIMESTAMP
);
1.\u501f\u4e66\u65f6\u81ea\u52a8\u51cf\u5c11\u5e93\u5b58
DELIMITER \/\/
CREATE TRIGGER trg_borrow_before_insert
BEFORE INSERT ON borrow
FOR EACH ROW
BEGIN
DECLARE v_stock INT;
SELECT stock INTO v_stock
FROM book
WHERE bno = NEW.bno;
IF v_stock <= 0 THEN
SIGNAL SQLSTATE '45000'
SET MESSAGE_TEXT = '\u5e93\u5b58\u4e0d\u8db3\uff0c\u4e0d\u80fd\u501f\u4e66';
ELSE
UPDATE book
SET stock = stock - 1
WHERE bno = NEW.bno;
END IF;
END \/\/
DELIMITER ;
\u6d4b\u8bd5\uff1a
SELECT stock FROM book WHERE bno='B003';
INSERT INTO borrow(rno,bno,borrowdate,returndate,actualdate)
VALUES('R2024002','B003','2025-05-01','2025-05-15',NULL);
SELECT stock FROM book WHERE bno='B003';
2.\u8fd8\u4e66\u65f6\u81ea\u52a8\u589e\u52a0\u5e93\u5b58\u5e76\u8ba1\u7b97\u7f5a\u6b3e
DELIMITER \/\/
CREATE TRIGGER trg_return_after_update
AFTER UPDATE ON borrow
FOR EACH ROW
BEGIN
IF OLD.actualdate IS NULL AND NEW.actualdate IS NOT NULL THEN
UPDATE book
SET stock = stock + 1
WHERE bno = NEW.bno;
UPDATE borrow
SET fine =
CASE
WHEN NEW.actualdate > NEW.returndate
THEN DATEDIFF(NEW.actualdate, NEW.returndate) * 1
ELSE 0
END
WHERE borrowid = NEW.borrowid;
END IF;
END \/\/
DELIMITER ;
\u6d4b\u8bd5\uff1a
UPDATE borrow
SET actualdate = '2025-05-18'
WHERE rno='R2024002'
AND bno='B003'
AND borrowdate='2025-05-01';
SELECT * FROM borrow
WHERE rno='R2024002'
AND bno='B003';
SELECT stock FROM book WHERE bno='B003';
3.\u5220\u9664\u8bfb\u8005\u524d\u8bb0\u5f55\u65e5\u5fd7
DELIMITER \/\/
CREATE TRIGGER trg_reader_before_delete
BEFORE DELETE ON reader
FOR EACH ROW
BEGIN
INSERT INTO reader_delete_log(rno,rname,dept)
VALUES(OLD.rno, OLD.rname, OLD.dept);
END \/\/
DELIMITER ;
\u6d4b\u8bd5\uff1a
INSERT INTO reader
VALUES('R2024888','\u65e5\u5fd7\u6d4b\u8bd5','\u7537','\u6d4b\u8bd5\u5b66\u9662','\u65e0');
DELETE FROM reader
WHERE rno='R2024888';
SELECT * FROM reader_delete_log;<\/pre>\n\n\n\n15.\u6570\u636e\u5b89\u5168\u6027<\/h2>\n\n\n\n1.\u521b\u5efa\u7528\u6237\u5e76\u6388\u4e88\u67e5\u8be2\u6743\u9650
CREATE USER 'lib_user1'@'localhost'
IDENTIFIED BY '123456';
GRANT SELECT
ON library_db.book
TO 'lib_user1'@'localhost';
\u67e5\u770b\u6743\u9650\uff1a
SHOW GRANTS FOR 'lib_user1'@'localhost';
2.\u6388\u4e88\u6743\u9650\u5e76\u5141\u8bb8\u8f6c\u6388\u6743
GRANT SELECT, INSERT
ON library_db.reader
TO 'lib_user1'@'localhost'
WITH GRANT OPTION;
\u8bf4\u660e\uff1a
WITH GRANT OPTION \u8868\u793a\u8be5\u7528\u6237\u53ef\u4ee5\u5c06\u81ea\u5df1\u62e5\u6709\u7684\u6743\u9650\u518d\u6388\u4e88\u5176\u4ed6\u7528\u6237\u3002
3.\u56de\u6536\u6743\u9650
REVOKE INSERT
ON library_db.reader
FROM 'lib_user1'@'localhost';
4.\u521b\u5efa\u89d2\u8272\u5e76\u6388\u6743
CREATE ROLE 'reader_role';
GRANT SELECT
ON library_db.*
TO 'reader_role';
CREATE USER 'lib_user2'@'localhost'
IDENTIFIED BY '123456';
GRANT 'reader_role'
TO 'lib_user2'@'localhost';
SET DEFAULT ROLE 'reader_role'
TO 'lib_user2'@'localhost';<\/pre>\n\n\n\n16.\u89c6\u56fe\u4e0e\u6d3e\u751f\u8868<\/h2>\n\n\n\n1.\u5e26\u805a\u5408\u51fd\u6570\u7684\u89c6\u56fe\uff1a\u7edf\u8ba1\u6bcf\u4e2a\u8bfb\u8005\u501f\u9605\u6b21\u6570
CREATE VIEW v_reader_borrow_count AS
SELECT r.rno, r.rname, COUNT(br.borrowid) AS borrow_count
FROM reader r
LEFT JOIN borrow br
ON r.rno = br.rno
GROUP BY r.rno, r.rname;
\u67e5\u8be2\uff1a
SELECT * FROM v_reader_borrow_count;
2.\u6d3e\u751f\u8868\uff1a\u67e5\u8be2\u501f\u9605\u6b21\u6570\u5927\u4e8e1\u7684\u8bfb\u8005
SELECT *
FROM (
SELECT rno, COUNT(*) AS borrow_count
FROM borrow
GROUP BY rno
) AS t
WHERE t.borrow_count > 1;
3.WITH \u5b50\u53e5\u7edf\u8ba1\u6bcf\u4f4d\u8bfb\u8005\u501f\u9605\u6570\u91cf
WITH reader_count AS (
SELECT rno, COUNT(*) AS total
FROM borrow
GROUP BY rno
)
SELECT r.rno, r.rname, rc.total
FROM reader r
LEFT JOIN reader_count rc
ON r.rno = rc.rno;
4.WITH \u5b50\u53e5\uff1a\u67e5\u8be2\u672a\u5f52\u8fd8\u56fe\u4e66
WITH unreturned AS (
SELECT br.borrowid, r.rname, b.bname,
br.borrowdate, br.returndate
FROM borrow br
JOIN reader r ON br.rno = r.rno
JOIN book b ON br.bno = b.bno
WHERE br.actualdate IS NULL
)
SELECT * FROM unreturned;<\/pre>\n\n\n\n17.\u6269\u5c55\u601d\u8003<\/h2>\n\n\n\n\n- \u5982\u4f55\u5904\u7406\u5206\u7c7b\u5b9e\u4f53\u7684\u81ea\u5173\u8054\uff1f<\/li>\n<\/ol>\n\n\n\n
\u5206\u7c7b\u5b9e\u4f53\u5b58\u5728\u201c\u4e0a\u7ea7\u5206\u7c7b\u201d\u548c\u201c\u4e0b\u7ea7\u5206\u7c7b\u201d\u7684\u5173\u7cfb\uff0c\u56e0\u6b64\u53ef\u4ee5\u5728 category \u8868\u4e2d\u8bbe\u7f6e parentid \u5b57\u6bb5\u3002
category(
cid,
cname,
parentid
)
\u5176\u4e2d cid \u662f\u5206\u7c7b\u7f16\u53f7\uff0cparentid \u662f\u4e0a\u7ea7\u5206\u7c7b\u7f16\u53f7\uff0c\u540c\u65f6 parentid \u4e5f\u662f\u6307\u5411 category.cid \u7684\u5916\u952e\u3002
\u5982\u679c\u67d0\u5206\u7c7b\u6ca1\u6709\u4e0a\u7ea7\u5206\u7c7b\uff0c\u5219 parentid \u53ef\u4ee5\u4e3a\u7a7a\u3002
\u8fd9\u79cd\u8bbe\u8ba1\u53ef\u4ee5\u8868\u793a\u6811\u5f62\u7ed3\u6784\uff0c\u4f8b\u5982\uff1a
\u56fe\u4e66
\u251c\u2500\u2500 \u8ba1\u7b97\u673a
\u2502 \u251c\u2500\u2500 \u6570\u636e\u5e93
\u2502 \u2514\u2500\u2500 \u7f51\u7edc\u6280\u672f
\u2514\u2500\u2500 \u6587\u5b66
\u2514\u2500\u2500 \u79d1\u5e7b\u5c0f\u8bf4<\/pre>\n\n\n\n
\n\n\n\n2. \u501f\u9605\u5173\u7cfb\u662f\u5426\u53ef\u80fd\u5b58\u5728\u6570\u636e\u5197\u4f59\uff1f<\/h2>\n\n\n\n\u501f\u9605\u8868\u5982\u679c\u53ea\u4fdd\u5b58 rno\u3001bno\u3001borrowdate\u3001returndate\u3001actualdate \u7b49\u4fe1\u606f\uff0c\u5219\u5197\u4f59\u8f83\u5c11\u3002
\u4f46\u662f\u5982\u679c\u5728 borrow \u8868\u4e2d\u540c\u65f6\u4fdd\u5b58\u8bfb\u8005\u59d3\u540d rname\u3001\u56fe\u4e66\u540d\u79f0 bname\u3001\u51fa\u7248\u793e press \u7b49\u4fe1\u606f\uff0c\u5c31\u4f1a\u4ea7\u751f\u6570\u636e\u5197\u4f59\u3002
\u4f8b\u5982\uff1a
borrow(borrowid, rno, rname, bno, bname, borrowdate)
\u5176\u4e2d rname \u4f9d\u8d56 rno\uff0cbname \u4f9d\u8d56 bno\uff0c\u800c\u4e0d\u662f\u76f4\u63a5\u4f9d\u8d56 borrowid\uff0c\u4f1a\u4ea7\u751f\u4f20\u9012\u4f9d\u8d56\u3002
\u89c4\u8303\u5316\u65b9\u6848\uff1a
\u5c06\u8bfb\u8005\u4fe1\u606f\u4fdd\u5b58\u5728 reader \u8868\uff1b
\u5c06\u56fe\u4e66\u4fe1\u606f\u4fdd\u5b58\u5728 book \u8868\uff1b
borrow \u8868\u53ea\u4fdd\u5b58\u8bfb\u8005\u8bc1\u53f7\u548c\u56fe\u4e66\u7f16\u53f7\u4f5c\u4e3a\u5916\u952e\u3002<\/pre>\n\n\n\n
\n\n\n\n3. \u5982\u4f55\u9632\u6b62\u5e93\u5b58\u4e3a\u8d1f\u6570\uff1f<\/h2>\n\n\n\n\u53ef\u4ee5\u4ece\u4e24\u4e2a\u65b9\u9762\u9632\u6b62\u5e93\u5b58\u4e3a\u8d1f\u6570\uff1a
\u7b2c\u4e00\uff0c\u5728 book \u8868\u4e2d\u8bbe\u7f6e CHECK(stock >= 0) \u7ea6\u675f\uff0c\u4fdd\u8bc1\u5e93\u5b58\u4e0d\u80fd\u5c0f\u4e8e0\u3002
\u7b2c\u4e8c\uff0c\u5728\u501f\u4e66\u89e6\u53d1\u5668\u4e2d\u5224\u65ad\u5e93\u5b58\u6570\u91cf\u3002
\u5f53\u63d2\u5165 borrow \u501f\u9605\u8bb0\u5f55\u65f6\uff0c\u5148\u67e5\u8be2\u56fe\u4e66\u5e93\u5b58\u3002
\u5982\u679c\u5e93\u5b58\u5c0f\u4e8e\u7b49\u4e8e0\uff0c\u5219\u4f7f\u7528 SIGNAL \u629b\u51fa\u9519\u8bef\uff0c\u963b\u6b62\u501f\u4e66\u64cd\u4f5c\uff1b
\u5982\u679c\u5e93\u5b58\u5927\u4e8e0\uff0c\u5219\u5141\u8bb8\u501f\u9605\uff0c\u5e76\u81ea\u52a8\u5c06\u5e93\u5b58\u51cf1\u3002
\u8fd9\u6837\u53ef\u4ee5\u4fdd\u8bc1\u501f\u4e66\u65f6\u4e0d\u4f1a\u51fa\u73b0\u5e93\u5b58\u4e3a\u8d1f\u6570\u7684\u60c5\u51b5\u3002<\/pre>\n\n\n\n
\n\n\n\n4. \u9884\u7ea6\u56fe\u4e66\u529f\u80fd\u9700\u8981\u589e\u52a0\u54ea\u4e9b\u5b9e\u4f53\u548c\u5173\u7cfb\uff1f<\/h2>\n\n\n\n\u5982\u679c\u7cfb\u7edf\u652f\u6301\u9884\u7ea6\u56fe\u4e66\u529f\u80fd\uff0c\u53ef\u4ee5\u589e\u52a0 reservation \u9884\u7ea6\u8868\u3002
reservation(
reserveid,
rno,
bno,
reservedate,
status
)
\u5176\u4e2d\uff1a
reserveid \u8868\u793a\u9884\u7ea6\u7f16\u53f7\uff1b
rno \u662f\u8bfb\u8005\u8bc1\u53f7\uff0c\u5916\u952e\u5f15\u7528 reader.rno\uff1b
bno \u662f\u56fe\u4e66\u7f16\u53f7\uff0c\u5916\u952e\u5f15\u7528 book.bno\uff1b
reservedate \u8868\u793a\u9884\u7ea6\u65e5\u671f\uff1b
status \u8868\u793a\u9884\u7ea6\u72b6\u6001\uff0c\u5982\u201c\u9884\u7ea6\u4e2d\u201d\u201c\u5df2\u53d6\u6d88\u201d\u201c\u5df2\u5b8c\u6210\u201d\u3002
\u65b0\u589e\u5173\u7cfb\uff1a
\u4e00\u4e2a\u8bfb\u8005\u53ef\u4ee5\u9884\u7ea6\u591a\u672c\u56fe\u4e66\uff1b
\u4e00\u672c\u56fe\u4e66\u53ef\u4ee5\u88ab\u591a\u4e2a\u8bfb\u8005\u9884\u7ea6\uff1b
\u8bfb\u8005\u548c\u56fe\u4e66\u4e4b\u95f4\u901a\u8fc7 reservation \u8868\u5f62\u6210 m:n \u8054\u7cfb\u3002<\/pre>\n\n\n\n
\n\n\n\n5. \u4e3a\u4ec0\u4e48\u9075\u5faa\u6700\u5c0f\u6743\u9650\u539f\u5219\uff1f<\/h2>\n\n\n\n\u6700\u5c0f\u6743\u9650\u539f\u5219\u662f\u6307\u53ea\u7ed9\u7528\u6237\u5b8c\u6210\u5de5\u4f5c\u6240\u5fc5\u9700\u7684\u6743\u9650\uff0c\u4e0d\u6388\u4e88\u591a\u4f59\u6743\u9650\u3002
\u5728\u672c\u5b9e\u9a8c\u4e2d\uff0c\u5982\u679c\u67d0\u7528\u6237\u53ea\u8d1f\u8d23\u67e5\u8be2\u56fe\u4e66\u4fe1\u606f\uff0c\u5219\u53ea\u6388\u4e88 SELECT \u6743\u9650\u5373\u53ef\uff0c\u4e0d\u5e94\u8be5\u6388\u4e88 INSERT\u3001UPDATE\u3001DELETE \u7b49\u6743\u9650\u3002
\u4f8b\u5982\uff1a
GRANT SELECT ON library_db.book TO 'lib_user1'@'localhost';
\u8fd9\u6837\u53ef\u4ee5\u9632\u6b62\u7528\u6237\u8bef\u5220\u3001\u8bef\u6539\u6570\u636e\uff0c\u63d0\u9ad8\u6570\u636e\u5e93\u5b89\u5168\u6027\u3002
\u5982\u679c\u540e\u7eed\u4e0d\u518d\u9700\u8981\u67d0\u9879\u6743\u9650\uff0c\u8fd8\u53ef\u4ee5\u4f7f\u7528 REVOKE \u56de\u6536\u6743\u9650\u3002<\/pre>\n\n\n\n
\n\n\n\n6. \u5e76\u53d1\u501f\u9605\u5e93\u5b58\u4ec5\u52691\u672c\u7684\u56fe\u4e66\u4f1a\u4ea7\u751f\u4ec0\u4e48\u95ee\u9898\uff1f\u5982\u4f55\u89e3\u51b3\uff1f<\/h2>\n\n\n\n\u5f53\u591a\u7528\u6237\u540c\u65f6\u501f\u9605\u540c\u4e00\u672c\u5e93\u5b58\u4ec5\u52691\u672c\u7684\u56fe\u4e66\u65f6\uff0c\u53ef\u80fd\u51fa\u73b0\u8d85\u5356\u95ee\u9898\u3002
\u4f8b\u5982\u4e24\u4e2a\u7528\u6237\u540c\u65f6\u8bfb\u53d6\u5e93\u5b58 stock=1\uff0c\u90fd\u8ba4\u4e3a\u53ef\u4ee5\u501f\u9605\uff0c\u7136\u540e\u540c\u65f6\u63d2\u5165\u501f\u9605\u8bb0\u5f55\u5e76\u6267\u884c\u5e93\u5b58\u51cf1\uff0c\u6700\u7ec8\u53ef\u80fd\u5bfc\u81f4\u5e93\u5b58\u5f02\u5e38\u6216\u51fa\u73b0\u8d85\u989d\u501f\u9605\u3002
\u89e3\u51b3\u65b9\u6cd5\uff1a
1. \u4f7f\u7528\u4e8b\u52a1\u4fdd\u8bc1\u501f\u4e66\u64cd\u4f5c\u7684\u539f\u5b50\u6027\uff1b
2. \u4f7f\u7528 SELECT ... FOR UPDATE \u5bf9\u56fe\u4e66\u5e93\u5b58\u8bb0\u5f55\u52a0\u884c\u7ea7\u9501\uff1b
3. \u5728\u89e6\u53d1\u5668\u4e2d\u5224\u65ad\u5e93\u5b58\u662f\u5426\u5927\u4e8e0\uff1b
4. \u7ed9 stock \u5b57\u6bb5\u8bbe\u7f6e CHECK(stock >= 0) \u7ea6\u675f\u3002
\u793a\u4f8b\uff1a
START TRANSACTION;
SELECT stock
FROM book
WHERE bno='B001'
FOR UPDATE;
UPDATE book
SET stock = stock - 1
WHERE bno='B001'
AND stock > 0;
INSERT INTO borrow(rno,bno,borrowdate,returndate)
VALUES('R2024001','B001','2025-05-01','2025-05-15');
COMMIT;
\u8fd9\u6837\u53ef\u4ee5\u907f\u514d\u591a\u4e2a\u7528\u6237\u540c\u65f6\u4fee\u6539\u5e93\u5b58\u5bfc\u81f4\u6570\u636e\u4e0d\u4e00\u81f4\u3002<\/pre>\n\n\n\n
\n\n\n\n\u5b9e\u9a8c\u603b\u7ed3<\/h1>\n\n\n\n \u901a\u8fc7\u672c\u6b21\u56fe\u4e66\u501f\u9605\u7ba1\u7406\u7cfb\u7edf\u7efc\u5408\u5b9e\u9a8c\uff0c\u6211\u7cfb\u7edf\u5730\u5b8c\u6210\u4e86\u6570\u636e\u5e93\u8bbe\u8ba1\u4e0e\u5b9e\u73b0\u7684\u5168\u8fc7\u7a0b\u3002\u5b9e\u9a8c\u4ece\u9700\u6c42\u5206\u6790\u5f00\u59cb\uff0c\u9010\u6b65\u5b8c\u6210 E-R \u56fe\u8bbe\u8ba1\u3001\u5173\u7cfb\u6a21\u5f0f\u8f6c\u6362\u3001\u7269\u7406\u8868\u7ed3\u6784\u8bbe\u8ba1\u3001\u6570\u636e\u63d2\u5165\u3001\u67e5\u8be2\u64cd\u4f5c\u3001\u89c6\u56fe\u3001\u7d22\u5f15\u3001\u5b8c\u6574\u6027\u7ea6\u675f\u3001\u89e6\u53d1\u5668\u548c\u6743\u9650\u7ba1\u7406\u7b49\u5185\u5bb9\uff0c\u4f7f\u6211\u5bf9\u6570\u636e\u5e93\u5e94\u7528\u7cfb\u7edf\u7684\u8bbe\u8ba1\u6d41\u7a0b\u6709\u4e86\u66f4\u52a0\u5b8c\u6574\u7684\u8ba4\u8bc6\u3002
\u200b
\u5728\u5b9e\u9a8c\u8fc7\u7a0b\u4e2d\uff0c\u6211\u9996\u5148\u6839\u636e\u56fe\u4e66\u9986\u4e1a\u52a1\u9700\u6c42\u5206\u6790\u51fa\u56fe\u4e66\u3001\u8bfb\u8005\u3001\u501f\u9605\u3001\u51fa\u7248\u793e\u3001\u5206\u7c7b\u7b49\u5b9e\u4f53\uff0c\u5e76\u660e\u786e\u4e86\u5b83\u4eec\u4e4b\u95f4\u7684\u8054\u7cfb\u7c7b\u578b\u3002\u4f8b\u5982\uff0c\u51fa\u7248\u793e\u4e0e\u56fe\u4e66\u4e4b\u95f4\u662f\u4e00\u5bf9\u591a\u5173\u7cfb\uff0c\u5206\u7c7b\u4e0e\u56fe\u4e66\u4e4b\u95f4\u662f\u4e00\u5bf9\u591a\u5173\u7cfb\uff0c\u8bfb\u8005\u4e0e\u56fe\u4e66\u4e4b\u95f4\u901a\u8fc7\u501f\u9605\u8868\u5f62\u6210\u591a\u5bf9\u591a\u5173\u7cfb\u3002\u901a\u8fc7 E-R \u56fe\u8bbe\u8ba1\uff0c\u6211\u8fdb\u4e00\u6b65\u7406\u89e3\u4e86\u6982\u5ff5\u7ed3\u6784\u8bbe\u8ba1\u5728\u6570\u636e\u5e93\u5f00\u53d1\u4e2d\u7684\u91cd\u8981\u4f5c\u7528\u3002
\u200b
\u5728\u903b\u8f91\u7ed3\u6784\u8bbe\u8ba1\u9636\u6bb5\uff0c\u6211\u5c06 E-R \u56fe\u8f6c\u6362\u4e3a\u5173\u7cfb\u6a21\u5f0f\uff0c\u5e76\u5206\u6790\u5404\u8868\u662f\u5426\u6ee1\u8db3\u7b2c\u4e09\u8303\u5f0f\u3002\u901a\u8fc7\u89c4\u8303\u5316\u8bbe\u8ba1\uff0c\u907f\u514d\u4e86\u5728\u501f\u9605\u8868\u4e2d\u91cd\u590d\u4fdd\u5b58\u8bfb\u8005\u59d3\u540d\u3001\u56fe\u4e66\u540d\u79f0\u7b49\u4fe1\u606f\uff0c\u51cf\u5c11\u4e86\u6570\u636e\u5197\u4f59\uff0c\u63d0\u9ad8\u4e86\u6570\u636e\u4e00\u81f4\u6027\u3002\u5728\u7269\u7406\u8bbe\u8ba1\u9636\u6bb5\uff0c\u6211\u4f7f\u7528 SQL \u521b\u5efa\u6570\u636e\u5e93\u548c\u6570\u636e\u8868\uff0c\u8bbe\u7f6e\u4e86\u4e3b\u952e\u3001\u5916\u952e\u3001\u975e\u7a7a\u3001\u9ed8\u8ba4\u503c\u548c CHECK \u7ea6\u675f\uff0c\u5bf9\u5b9e\u4f53\u5b8c\u6574\u6027\u3001\u53c2\u7167\u5b8c\u6574\u6027\u548c\u7528\u6237\u5b9a\u4e49\u5b8c\u6574\u6027\u6709\u4e86\u66f4\u6df1\u523b\u7684\u7406\u89e3\u3002
\u200b
\u5728\u6570\u636e\u64cd\u4f5c\u90e8\u5206\uff0c\u6211\u7ec3\u4e60\u4e86 INSERT\u3001UPDATE\u3001DELETE \u548c SELECT \u8bed\u53e5\uff0c\u5e76\u5b8c\u6210\u4e86\u57fa\u7840\u67e5\u8be2\u3001\u805a\u5408\u67e5\u8be2\u3001\u591a\u8868\u8fde\u63a5\u67e5\u8be2\u3001\u5d4c\u5957\u67e5\u8be2\u548c\u96c6\u5408\u67e5\u8be2\u7b49\u5185\u5bb9\u3002\u901a\u8fc7\u8fd9\u4e9b\u7ec3\u4e60\uff0c\u6211\u638c\u63e1\u4e86 SQL \u67e5\u8be2\u8bed\u53e5\u7684\u5e38\u89c1\u5199\u6cd5\uff0c\u5c24\u5176\u662f\u591a\u8868\u8fde\u63a5\u548c\u5d4c\u5957\u67e5\u8be2\u7684\u4f7f\u7528\u65b9\u6cd5\u3002\u5b9e\u9a8c\u4e2d\u8fd8\u521b\u5efa\u4e86\u89c6\u56fe\u548c\u7d22\u5f15\uff0c\u7406\u89e3\u4e86\u89c6\u56fe\u53ef\u4ee5\u7b80\u5316\u590d\u6742\u67e5\u8be2\uff0c\u7d22\u5f15\u53ef\u4ee5\u63d0\u9ad8\u67e5\u8be2\u6548\u7387\uff0c\u4f46\u4e5f\u4f1a\u589e\u52a0\u7ef4\u62a4\u6210\u672c\u3002
\u200b
\u5728\u89e6\u53d1\u5668\u90e8\u5206\uff0c\u6211\u5b9e\u73b0\u4e86\u501f\u4e66\u81ea\u52a8\u51cf\u5c11\u5e93\u5b58\u3001\u8fd8\u4e66\u81ea\u52a8\u589e\u52a0\u5e93\u5b58\u5e76\u8ba1\u7b97\u7f5a\u6b3e\u3001\u5220\u9664\u8bfb\u8005\u524d\u8bb0\u5f55\u65e5\u5fd7\u7b49\u529f\u80fd\u3002\u901a\u8fc7\u89e6\u53d1\u5668\u5b9e\u9a8c\uff0c\u6211\u8ba4\u8bc6\u5230\u6570\u636e\u5e93\u4e0d\u4ec5\u53ef\u4ee5\u5b58\u50a8\u6570\u636e\uff0c\u8fd8\u53ef\u4ee5\u5728\u7279\u5b9a\u64cd\u4f5c\u53d1\u751f\u65f6\u81ea\u52a8\u6267\u884c\u4e00\u4e9b\u4e1a\u52a1\u903b\u8f91\u3002\u5b9e\u9a8c\u8fc7\u7a0b\u4e2d\u4e5f\u9047\u5230\u4e86\u4e00\u4e9b\u95ee\u9898\uff0c\u4f8b\u5982\u5916\u952e\u7ea6\u675f\u5bfc\u81f4\u6570\u636e\u65e0\u6cd5\u5220\u9664\u3001CHECK \u7ea6\u675f\u63d2\u5165\u5931\u8d25\u3001\u89e6\u53d1\u5668\u8bed\u6cd5\u9519\u8bef\u7b49\u3002\u901a\u8fc7\u67e5\u770b\u9519\u8bef\u4fe1\u606f\u3001\u4fee\u6539 SQL \u8bed\u53e5\u548c\u53cd\u590d\u6d4b\u8bd5\uff0c\u6700\u7ec8\u89e3\u51b3\u4e86\u8fd9\u4e9b\u95ee\u9898\u3002
\u200b
\u901a\u8fc7\u672c\u6b21\u5b9e\u9a8c\uff0c\u6211\u4e0d\u4ec5\u5de9\u56fa\u4e86\u6570\u636e\u5e93\u7406\u8bba\u77e5\u8bc6\uff0c\u4e5f\u63d0\u9ad8\u4e86 SQL \u7f16\u5199\u80fd\u529b\u548c\u6570\u636e\u5e93\u8c03\u8bd5\u80fd\u529b\u3002\u4eca\u540e\u5728\u8bbe\u8ba1\u6570\u636e\u5e93\u7cfb\u7edf<\/pre>\n","protected":false},"excerpt":{"rendered":"\u6570\u636e\u5e93\u7efc\u5408\u5b9e\u9a8c 1.\u9700\u6c42\u5206\u6790 \u67d0\u5927\u578b\u56fe\u4e66\u9986\u9700\u8981\u5f00\u53d1\u4e00\u5957\u6570\u5b57\u5316\u501f\u9605\u7ba1\u7406\u7cfb\u7edf\uff0c\u4e3b\u8981\u4e1a\u52a1\u9700\u6c42\u5982\u4e0b\uff1a \u56fe\u4e66\u4fe1\u606f\uff1a\u8bb0\u5f55\u56fe […]<\/p>\n","protected":false},"author":1,"featured_media":448,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[9],"tags":[],"class_list":["post-446","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-wenzhang"],"_links":{"self":[{"href":"https:\/\/fg2025.cn\/index.php\/wp-json\/wp\/v2\/posts\/446","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/fg2025.cn\/index.php\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/fg2025.cn\/index.php\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/fg2025.cn\/index.php\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/fg2025.cn\/index.php\/wp-json\/wp\/v2\/comments?post=446"}],"version-history":[{"count":0,"href":"https:\/\/fg2025.cn\/index.php\/wp-json\/wp\/v2\/posts\/446\/revisions"}],"wp:attachment":[{"href":"https:\/\/fg2025.cn\/index.php\/wp-json\/wp\/v2\/media?parent=446"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/fg2025.cn\/index.php\/wp-json\/wp\/v2\/categories?post=446"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/fg2025.cn\/index.php\/wp-json\/wp\/v2\/tags?post=446"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}
CHARACTER SET utf8mb4;
USE library_db;<\/pre>\n\n\n\n
3.2\u521b\u5efa\u6570\u636e\u5e93\u8868<\/h3>\n\n\n\n CREATE TABLE book(
bno CHAR(10) PRIMARY KEY,
bname VARCHAR(50) NOT NULL,
author VARCHAR(30),
press VARCHAR(30),
pubyear INT,
stock INT DEFAULT 1 CHECK(stock>=0)
);
CREATE TABLE reader(
rno CHAR(12) PRIMARY KEY,
rname VARCHAR(20) NOT NULL,
rsex CHAR(1)
CHECK(rsex IN('\u7537','\u5973')),
dept VARCHAR(40),
phone VARCHAR(20)
);
CREATE TABLE borrow(
borrowid INT AUTO_INCREMENT PRIMARY KEY,
rno CHAR(12) NOT NULL,
bno CHAR(10) NOT NULL,
borrowdate DATE NOT NULL,
returndate DATE NOT NULL,
actualdate DATE,
CONSTRAINT fk_reader
FOREIGN KEY(rno)
REFERENCES reader(rno)
ON DELETE RESTRICT
ON UPDATE CASCADE,
CONSTRAINT fk_book
FOREIGN KEY(bno)
REFERENCES book(bno)
ON DELETE RESTRICT
ON UPDATE CASCADE
);
desc book;
desc reader;
desc borrow;<\/pre>\n\n\n\n<\/div><\/figure>\n\n\n\n<\/div><\/figure>\n\n\n\n<\/div><\/figure>\n\n\n\n<\/div><\/figure>\n\n\n\n3.3 \u6dfb\u52a0\u4fee\u6539\u5220\u9664\u5b57\u6bb5<\/h3>\n\n\n\n ALTER TABLE book
ADD pages INT;
\u200b
ALTER TABLE reader
ADD email VARCHAR(50) UNIQUE;
\u200b
\u9a8c\u8bc1\uff1a
desc book
desc reader
\u200b
ALTER TABLE book
MODIFY author VARCHAR(50);
\u200b
ALTER TABLE reader
MODIFY phone VARCHAR(20)
DEFAULT '\u65e0';
\u200b
SHOW CREATE TABLE borrow;
ALTER TABLE book
DROP COLUMN pages;
\u200b
ALTER TABLE borrow
DROP FOREIGN KEY fk_reader;<\/pre>\n\n\n\n4.\u6570\u636e\u63d2\u5165<\/h2>\n\n\n\n INSERT INTO book VALUES
('B001','\u6570\u636e\u5e93\u7cfb\u7edf\u6982\u8bba','\u738b\u73ca',
'\u9ad8\u7b49\u6559\u80b2\u51fa\u7248\u793e',2018,5),
\u200b
('B002','C\u7a0b\u5e8f\u8bbe\u8ba1\u8bed\u8a00','K&R',
'\u673a\u68b0\u5de5\u4e1a\u51fa\u7248\u793e',2015,3),
\u200b
('B003','\u4e09\u4f53','\u5218\u6148\u6b23',
'\u91cd\u5e86\u51fa\u7248\u793e',2010,8),
\u200b
('B004','\u8ba1\u7b97\u673a\u7f51\u7edc','\u8c22\u5e0c\u4ec1',
'\u7535\u5b50\u5de5\u4e1a\u51fa\u7248\u793e',2018,4);
\u200b
INSERT INTO reader
VALUES
('R2024001','\u5f20\u660e','\u7537',
'\u8ba1\u7b97\u673a\u5b66\u9662','13812345678',
'zhangming@qq.com'),
\u200b
('R2024002','\u674e\u82b3','\u5973',
'\u4fe1\u606f\u5b66\u9662','13912345678',
'lifang@qq.com'),
\u200b
('R2024003','\u738b\u78ca','\u7537',
'\u6587\u5b66\u9662','13612345678',
'wanglei@qq.com');
\u200b
INSERT INTO borrow VALUES
(1,'R2024001','B001',
'2025-03-01',
'2025-03-15',
'2025-03-14'),
(2,'R2024001','B003',
'2025-03-10',
'2025-03-24',
NULL),
(3,'R2024002','B002',
'2025-04-01',
'2025-04-15',
NULL),
(4,'R2024003','B004',
'2025-03-20',
'2025-04-03',
'2025-04-05');<\/pre>\n\n\n\n4.1 \u8bbe\u8ba1\u8fdd\u53cd\u5916\u952e\u7ea6\u675f\u548ccheck\u7ea6\u675f\u5e76\u89e3\u91ca<\/h3>\n\n\n\n INSERT INTO borrow(
rno,bno,
borrowdate,
returndate)
VALUES(
'R999999',
'B001',
'2025-05-01',
'2025-05-15');
\u200b
\u9519\u8bef\uff1aCannot add or update a child row:
a foreign key constraint fails
\u200b
\u539f\u56e0\uff1aR999999\u5728reader\u8868\u4e2d\u4e0d\u5b58\u5728\uff0c
\u8fdd\u53cd\u53c2\u7167\u5b8c\u6574\u6027\u7ea6\u675f\u3002
\u200b
\u8fdd\u53cdcheck
INSERT INTO reader
VALUES(
'R2024004',
'\u8d75\u654f',
'\u672a\u77e5',
'\u827a\u672f\u5b66\u9662',
'13712345678');
\u200b
\u9519\u8bef\uff1aCheck constraint violated
\u200b
\u539f\u56e0\uff1arsex\u5b57\u6bb5\u53ea\u80fd\u53d6
\u7537 \u6216 \u5973\uff0c
\u56e0\u6b64\u8fdd\u53cdCHECK\u7ea6\u675f\u3002<\/pre>\n\n\n\n5.\u6570\u636e\u67e5\u8be2\uff08DQL-\u57fa\u7840\u67e5\u8be2\uff09<\/h2>\n\n\n\n 1.select\u67e5\u8be2\u5168\u90e8\u56fe\u4e66\u4fe1\u606f
select * from book;
2.\u67e5\u8be2\u5e93\u5b58\u5927\u4e8e3\u7684\u56fe\u4e66
SELECT bno,bname,stock
FROM book
WHERE stock > 3;
3.\u67e5\u8be22018\u5e74\u51fa\u7248\u4e14\u5e93\u5b58\u4e0d\u5c11\u4e8e4\u672c\u7684\u56fe\u4e66
SELECT bno,bname,pubyear,stock
FROM book
WHERE pubyear = 2018 AND stock >= 4;
4.\u67e5\u8be22015\u5e74\u81f32018\u5e74\u51fa\u7248\u7684\u56fe\u4e66
SELECT bno,bname,pubyear
FROM book
WHERE pubyear BETWEEN 2015 AND 2018;
5.\u67e5\u8be2\u51fa\u7248\u793e\u4e3a\u201c\u91cd\u5e86\u51fa\u7248\u793e\u201d\u6216\u201c\u9ad8\u7b49\u6559\u80b2\u51fa\u7248\u793e\u201d\u7684\u56fe\u4e66
SELECT bno,bname,press
FROM book
WHERE press IN('\u91cd\u5e86\u51fa\u7248\u793e','\u9ad8\u7b49\u6559\u80b2\u51fa\u7248\u793e');
6.\u67e5\u8be2\u4e66\u540d\u4e2d\u5305\u542b\u201c\u8ba1\u7b97\u673a\u201d\u7684\u56fe\u4e66
SELECT bno,bname
FROM book
WHERE bname LIKE '%\u8ba1\u7b97\u673a%';
7.\u67e5\u8be2\u5c1a\u672a\u5f52\u8fd8\u7684\u501f\u9605\u8bb0\u5f55
SELECT *
FROM borrow
WHERE actualdate IS NULL;
8.\u6309\u5e93\u5b58\u6570\u91cf\u964d\u5e8f\u67e5\u8be2\u56fe\u4e66
SELECT bno,bname,stock
FROM book
ORDER BY stock DESC;
9.\u67e5\u8be2\u5e93\u5b58\u6700\u591a\u7684\u524d2\u672c\u56fe\u4e66
SELECT bno,bname,stock
FROM book
ORDER BY stock DESC
LIMIT 2;
10.\u67e5\u8be2\u6240\u6709\u4e0d\u540c\u7684\u51fa\u7248\u793e
SELECT DISTINCT press
FROM book;<\/pre>\n\n\n\n6.\u6570\u636e\u66f4\u65b0\uff08update\/delete\uff09<\/h2>\n\n\n\n 1.\u5c06BOO1\u7684\u5e93\u5b58\u4fee\u6539\u4e3a6
UPDATE book
SET stock = 6
WHERE bno = 'B001';
\u200b
SELECT * FROM book WHERE bno='B001';
2.\u4fee\u6539\u5f20\u660e\u7684\u9662\u7cfb\u548c\u7535\u8bdd
UPDATE reader
SET dept = '\u4eba\u5de5\u667a\u80fd\u5b66\u9662',
phone = '18888888888'
WHERE rno = 'R2024001';
\u200b
SELECT * FROM reader WHERE rno='R2024001';
3.\u5c062018\u5e74\u51fa\u7248\u56fe\u4e66\u5e93\u5b58\u7edf\u4e00\u589e\u52a01
UPDATE book
SET stock = stock + 1
WHERE pubyear = 2018;
\u200b
SELECT * FROM book WHERE pubyear=2018;
4.\u5220\u9664\u4e00\u4e2a\u6d4b\u8bd5\u8bfb\u8005
INSERT INTO reader
VALUES('R2024999','\u6d4b\u8bd5\u8bfb\u8005','\u7537','\u6d4b\u8bd5\u5b66\u9662','\u65e0');
\u200b
DELETE FROM reader
WHERE rno = 'R2024999';
5.\u4e8b\u52a1\u63a7\u5236\uff1a\u66f4\u65b0\u540e\u56de\u6eda
START TRANSACTION;
\u200b
UPDATE book
SET stock = stock - 1
WHERE bno = 'B003';
\u200b
SELECT * FROM book WHERE bno='B003';
\u200b
ROLLBACK;
\u200b
SELECT * FROM book WHERE bno='B003';<\/pre>\n\n\n\n7.\u805a\u5408\u67e5\u8be2\u4e0e\u5206\u7ec4\u7edf\u8ba1<\/h2>\n\n\n\n 1.\u7edf\u8ba1\u56fe\u4e66\u603b\u6570
select count(*) as \u56fe\u4e66\u603b\u6570 from book;
2.\u7edf\u8ba1\u56fe\u4e66\u5e93\u5b58\u603b\u91cf
select sum(stock) as \u5e93\u5b58\u603b\u91cf from book;
3.\u7edf\u8ba1\u5e73\u5747\u5e93\u5b58
select avg(stock) as \u5e73\u5747\u5e93\u5b58 from book;
4.\u67e5\u8be2\u6700\u5927\u5e93\u5b58\u548c\u6700\u5c0f\u5e93\u5b58
SELECT MAX(stock) AS \u6700\u5927\u5e93\u5b58,
MIN(stock) AS \u6700\u5c0f\u5e93\u5b58
FROM book;
5.\u6309\u51fa\u7248\u793e\u7edf\u8ba1\u56fe\u4e66\u6570\u91cf\uff0c\u5e76\u7b5b\u9009\u6570\u91cf\u5927\u4e8e\u7b49\u4e8e1\u7684\u51fa\u7248\u793e
SELECT press, COUNT(*) AS \u56fe\u4e66\u6570\u91cf
FROM book
GROUP BY press
HAVING COUNT(*) >= 1;<\/pre>\n\n\n\n8.\u591a\u8868\u8fde\u63a5\u67e5\u8be2<\/h2>\n\n\n\n1.\u7b49\u503c\u8fde\u63a5\uff1a\u67e5\u8be2\u8bfb\u8005\u59d3\u540d\u548c\u6240\u501f\u56fe\u4e66
SELECT reader.rname, book.bname
FROM reader, borrow, book
WHERE reader.rno = borrow.rno
AND borrow.bno = book.bno;
2.\u5185\u8fde\u63a5\uff1a\u67e5\u8be2\u501f\u9605\u8bb0\u5f55\u8be6\u60c5
SELECT r.rname, b.bname, br.borrowdate, br.returndate
FROM borrow br
JOIN reader r ON br.rno = r.rno
JOIN book b ON br.bno = b.bno;
3.\u5de6\u5916\u8fde\u63a5\uff1a\u67e5\u8be2\u6240\u6709\u8bfb\u8005\u53ca\u5176\u501f\u9605\u8bb0\u5f55
SELECT r.rno, r.rname, br.borrowid, br.bno
FROM reader r
LEFT JOIN borrow br
ON r.rno = br.rno;
4.\u53f3\u5916\u8fde\u63a5\uff1a\u67e5\u8be2\u6240\u6709\u501f\u9605\u8bb0\u5f55\u53ca\u8bfb\u8005\u4fe1\u606f
SELECT r.rname, br.borrowid, br.bno
FROM reader r
RIGHT JOIN borrow br
ON r.rno = br.rno;
5.\u81ea\u8eab\u8fde\u63a5\uff1a\u67e5\u8be2\u540c\u4e00\u5e74\u51fa\u7248\u7684\u4e0d\u540c\u56fe\u4e66
SELECT a.bname AS \u56fe\u4e661,
b.bname AS \u56fe\u4e662,
a.pubyear AS \u51fa\u7248\u5e74\u4efd
FROM book a
JOIN book b
ON a.pubyear = b.pubyear
AND a.bno < b.bno;<\/pre>\n\n\n\n9.\u5d4c\u5957\u67e5\u8be2<\/h2>\n\n\n\n1.IN\uff1a\u67e5\u8be2\u501f\u8fc7\u4e66\u7684\u8bfb\u8005
SELECT *
FROM reader
WHERE rno IN(
SELECT rno FROM borrow
);
2.\u6bd4\u8f83\u8fd0\u7b97\u7b26\uff1a\u67e5\u8be2\u5e93\u5b58\u5927\u4e8e\u5e73\u5747\u5e93\u5b58\u7684\u56fe\u4e66
SELECT bno,bname,stock
FROM book
WHERE stock > (
SELECT AVG(stock)
FROM book
);
3.EXISTS\uff1a\u67e5\u8be2\u5b58\u5728\u501f\u9605\u8bb0\u5f55\u7684\u8bfb\u8005
SELECT *
FROM reader r
WHERE EXISTS(
SELECT *
FROM borrow br
WHERE br.rno = r.rno
);
4.ANY\uff1a\u67e5\u8be2\u5e93\u5b58\u5927\u4e8e\u4efb\u610f\u4e00\u672c2018\u5e74\u51fa\u7248\u56fe\u4e66\u5e93\u5b58\u7684\u56fe\u4e66
SELECT bno,bname,stock
FROM book
WHERE stock > ANY(
SELECT stock
FROM book
WHERE pubyear = 2018
);
5.ALL\uff1a\u67e5\u8be2\u5e93\u5b58\u4e0d\u5c11\u4e8e\u6240\u6709\u56fe\u4e66\u5e93\u5b58\u7684\u56fe\u4e66
SELECT bno,bname,stock
FROM book
WHERE stock >= ALL(
SELECT stock
FROM book
);<\/pre>\n\n\n\n10.\u96c6\u5408\u67e5\u8be2<\/h2>\n\n\n\n1.UNION\uff1a\u5408\u5e76\u8bfb\u8005\u59d3\u540d\u548c\u4f5c\u8005\u59d3\u540d\u5e76\u53bb\u91cd
SELECT rname AS name
FROM reader
UNION
SELECT author AS name
FROM book;
2.UNION ALL\uff1a\u5408\u5e76\u8bfb\u8005\u59d3\u540d\u548c\u4f5c\u8005\u59d3\u540d\uff0c\u4e0d\u53bb\u91cd
SELECT rname AS name
FROM reader
UNION ALL
SELECT author AS name
FROM book;
3.\u6a21\u62df INTERSECT\uff1a\u67e5\u8be2\u501f\u8fc7\u4e66\u7684\u8bfb\u8005\u8bc1\u53f7
SELECT rno
FROM reader
WHERE rno IN(
SELECT rno
FROM borrow
);
4.\u6a21\u62df EXCEPT\uff1a\u67e5\u8be2\u6ca1\u6709\u501f\u4e66\u7684\u8bfb\u8005
SELECT rno,rname
FROM reader
WHERE rno NOT IN(
SELECT rno
FROM borrow
);<\/pre>\n\n\n\n11.\u89c6\u56fe\u64cd\u4f5c<\/h2>\n\n\n\n1.\u521b\u5efa\u672a\u5f52\u8fd8\u56fe\u4e66\u89c6\u56fe
CREATE VIEW v_unreturned AS
SELECT br.borrowid, r.rname, b.bname,
br.borrowdate, br.returndate
FROM borrow br
JOIN reader r ON br.rno = r.rno
JOIN book b ON br.bno = b.bno
WHERE br.actualdate IS NULL;
2.\u67e5\u8be2\u89c6\u56fe
SELECT * FROM v_unreturned;
3.\u521b\u5efa\u5b66\u751f\u8bfb\u8005\u89c6\u56fe\uff0c\u5e26 WITH CHECK OPTION
CREATE VIEW v_student_reader AS
SELECT *
FROM reader
WHERE dept LIKE '%\u5b66\u9662%'
WITH CHECK OPTION;
4.\u6d4b\u8bd5\u53ef\u66f4\u65b0\u89c6\u56fe
UPDATE v_student_reader
SET phone = '18800000000'
WHERE rno = 'R2024002';
\u8bf4\u660e\uff1a
\u8be5\u89c6\u56fe\u57fa\u4e8e\u5355\u8868 reader \u521b\u5efa\uff0c\u6ca1\u6709\u805a\u5408\u51fd\u6570\u3001\u5206\u7ec4\u548c\u8fde\u63a5\uff0c\u56e0\u6b64\u5c5e\u4e8e\u53ef\u66f4\u65b0\u89c6\u56fe\u3002
5.\u521b\u5efa\u4e0d\u53ef\u66f4\u65b0\u7684\u805a\u5408\u89c6\u56fe
CREATE VIEW v_press_count AS
SELECT press, COUNT(*) AS total
FROM book
GROUP BY press;
\u8bf4\u660e\uff1a
\u8be5\u89c6\u56fe\u4f7f\u7528\u4e86 GROUP BY \u548c COUNT \u805a\u5408\u51fd\u6570\uff0c\u56e0\u6b64\u4e00\u822c\u4e0d\u80fd\u76f4\u63a5\u66f4\u65b0\u3002
6.\u5220\u9664\u89c6\u56fe
DROP VIEW v_unreturned;
DROP VIEW v_student_reader;
DROP VIEW v_press_count;<\/pre>\n\n\n\n12.\u7d22\u5f15<\/h2>\n\n\n\n1.\u521b\u5efa\u666e\u901a\u7d22\u5f15
CREATE INDEX idx_book_bname
ON book(bname);
2.\u521b\u5efa\u552f\u4e00\u7d22\u5f15
CREATE UNIQUE INDEX idx_reader_phone
ON reader(phone);
3.\u521b\u5efa\u590d\u5408\u7d22\u5f15
CREATE INDEX idx_borrow_rno_bno
ON borrow(rno,bno);
\u67e5\u770b\u7d22\u5f15
SHOW INDEX FROM book;
SHOW INDEX FROM reader;
SHOW INDEX FROM borrow;
\u5220\u9664\u7d22\u5f15
DROP INDEX idx_book_bname ON book;
DROP INDEX idx_reader_phone ON reader;
DROP INDEX idx_borrow_rno_bno ON borrow;<\/pre>\n\n\n\n13.\u6570\u636e\u5b8c\u6574\u6027\u7ea6\u675f\u9a8c\u8bc1\u4e0e\u7ea7\u8054\u64cd\u4f5c<\/h2>\n\n\n\n1.\u5b9e\u4f53\u5b8c\u6574\u6027\u9a8c\u8bc1\uff1a\u4e3b\u952e\u4e0d\u80fd\u4e3a\u7a7a
INSERT INTO book(bno,bname,author,press,pubyear,stock)
VALUES(NULL,'\u6d4b\u8bd5\u4e66','\u6d4b\u8bd5\u4f5c\u8005','\u6d4b\u8bd5\u51fa\u7248\u793e',2020,1);
\u8bf4\u660e\uff1a
bno \u662f book \u8868\u4e3b\u952e\uff0c\u4e3b\u952e\u4e0d\u80fd\u4e3a\u7a7a\uff0c\u56e0\u6b64\u63d2\u5165\u5931\u8d25\u3002
2.\u53c2\u7167\u5b8c\u6574\u6027\u9a8c\u8bc1\uff1a\u63d2\u5165\u4e0d\u5b58\u5728\u7684\u56fe\u4e66\u7f16\u53f7
INSERT INTO borrow(rno,bno,borrowdate,returndate,actualdate)
VALUES('R2024001','B999','2025-05-01','2025-05-15',NULL);
\u8bf4\u660e\uff1a
B999 \u5728 book \u8868\u4e2d\u4e0d\u5b58\u5728\uff0cborrow.bno \u662f\u5916\u952e\uff0c\u56e0\u6b64\u8fdd\u53cd\u53c2\u7167\u5b8c\u6574\u6027\u3002
3.\u7528\u6237\u5b9a\u4e49\u5b8c\u6574\u6027\u9a8c\u8bc1\uff1a\u5e93\u5b58\u4e0d\u80fd\u5c0f\u4e8e0
UPDATE book
SET stock = -1
WHERE bno = 'B001';
\u8bf4\u660e\uff1a
stock \u5b57\u6bb5\u8bbe\u7f6e\u4e86 CHECK(stock>=0)\uff0c\u5e93\u5b58\u4e0d\u80fd\u4e3a\u8d1f\u6570\u3002
4.\u7528\u6237\u5b9a\u4e49\u5b8c\u6574\u6027\u9a8c\u8bc1\uff1a\u5e93\u5b58\u4e0d\u80fd\u5c0f\u4e8e0
UPDATE book
SET stock = -1
WHERE bno = 'B001';
\u8bf4\u660e\uff1a
stock \u5b57\u6bb5\u8bbe\u7f6e\u4e86 CHECK(stock>=0)\uff0c\u5e93\u5b58\u4e0d\u80fd\u4e3a\u8d1f\u6570\u3002
5.ON UPDATE CASCADE \u6d4b\u8bd5
UPDATE reader
SET rno = 'R2024999'
WHERE rno = 'R2024003';
SELECT * FROM borrow
WHERE rno = 'R2024999';
\u8bf4\u660e\uff1a
reader.rno \u66f4\u65b0\u540e\uff0cborrow \u8868\u4e2d\u5bf9\u5e94\u7684\u5916\u952e rno \u4f1a\u81ea\u52a8\u540c\u6b65\u66f4\u65b0\u3002<\/pre>\n\n\n\n14.\u89e6\u53d1\u5668<\/h2>\n\n\n\n\u51c6\u5907\uff1a\u5220\u9664\u65e7\u89e6\u53d1\u5668
DROP TRIGGER IF EXISTS trg_borrow_before_insert;
DROP TRIGGER IF EXISTS trg_return_after_update;
DROP TRIGGER IF EXISTS trg_reader_before_delete;
\u521b\u5efa\u5220\u9664\u8bfb\u8005\u65e5\u5fd7\u8868
CREATE TABLE reader_delete_log(
logid INT AUTO_INCREMENT PRIMARY KEY,
rno CHAR(12),
rname VARCHAR(20),
dept VARCHAR(40),
delete_time DATETIME DEFAULT CURRENT_TIMESTAMP
);
1.\u501f\u4e66\u65f6\u81ea\u52a8\u51cf\u5c11\u5e93\u5b58
DELIMITER \/\/
CREATE TRIGGER trg_borrow_before_insert
BEFORE INSERT ON borrow
FOR EACH ROW
BEGIN
DECLARE v_stock INT;
SELECT stock INTO v_stock
FROM book
WHERE bno = NEW.bno;
IF v_stock <= 0 THEN
SIGNAL SQLSTATE '45000'
SET MESSAGE_TEXT = '\u5e93\u5b58\u4e0d\u8db3\uff0c\u4e0d\u80fd\u501f\u4e66';
ELSE
UPDATE book
SET stock = stock - 1
WHERE bno = NEW.bno;
END IF;
END \/\/
DELIMITER ;
\u6d4b\u8bd5\uff1a
SELECT stock FROM book WHERE bno='B003';
INSERT INTO borrow(rno,bno,borrowdate,returndate,actualdate)
VALUES('R2024002','B003','2025-05-01','2025-05-15',NULL);
SELECT stock FROM book WHERE bno='B003';
2.\u8fd8\u4e66\u65f6\u81ea\u52a8\u589e\u52a0\u5e93\u5b58\u5e76\u8ba1\u7b97\u7f5a\u6b3e
DELIMITER \/\/
CREATE TRIGGER trg_return_after_update
AFTER UPDATE ON borrow
FOR EACH ROW
BEGIN
IF OLD.actualdate IS NULL AND NEW.actualdate IS NOT NULL THEN
UPDATE book
SET stock = stock + 1
WHERE bno = NEW.bno;
UPDATE borrow
SET fine =
CASE
WHEN NEW.actualdate > NEW.returndate
THEN DATEDIFF(NEW.actualdate, NEW.returndate) * 1
ELSE 0
END
WHERE borrowid = NEW.borrowid;
END IF;
END \/\/
DELIMITER ;
\u6d4b\u8bd5\uff1a
UPDATE borrow
SET actualdate = '2025-05-18'
WHERE rno='R2024002'
AND bno='B003'
AND borrowdate='2025-05-01';
SELECT * FROM borrow
WHERE rno='R2024002'
AND bno='B003';
SELECT stock FROM book WHERE bno='B003';
3.\u5220\u9664\u8bfb\u8005\u524d\u8bb0\u5f55\u65e5\u5fd7
DELIMITER \/\/
CREATE TRIGGER trg_reader_before_delete
BEFORE DELETE ON reader
FOR EACH ROW
BEGIN
INSERT INTO reader_delete_log(rno,rname,dept)
VALUES(OLD.rno, OLD.rname, OLD.dept);
END \/\/
DELIMITER ;
\u6d4b\u8bd5\uff1a
INSERT INTO reader
VALUES('R2024888','\u65e5\u5fd7\u6d4b\u8bd5','\u7537','\u6d4b\u8bd5\u5b66\u9662','\u65e0');
DELETE FROM reader
WHERE rno='R2024888';
SELECT * FROM reader_delete_log;<\/pre>\n\n\n\n15.\u6570\u636e\u5b89\u5168\u6027<\/h2>\n\n\n\n1.\u521b\u5efa\u7528\u6237\u5e76\u6388\u4e88\u67e5\u8be2\u6743\u9650
CREATE USER 'lib_user1'@'localhost'
IDENTIFIED BY '123456';
GRANT SELECT
ON library_db.book
TO 'lib_user1'@'localhost';
\u67e5\u770b\u6743\u9650\uff1a
SHOW GRANTS FOR 'lib_user1'@'localhost';
2.\u6388\u4e88\u6743\u9650\u5e76\u5141\u8bb8\u8f6c\u6388\u6743
GRANT SELECT, INSERT
ON library_db.reader
TO 'lib_user1'@'localhost'
WITH GRANT OPTION;
\u8bf4\u660e\uff1a
WITH GRANT OPTION \u8868\u793a\u8be5\u7528\u6237\u53ef\u4ee5\u5c06\u81ea\u5df1\u62e5\u6709\u7684\u6743\u9650\u518d\u6388\u4e88\u5176\u4ed6\u7528\u6237\u3002
3.\u56de\u6536\u6743\u9650
REVOKE INSERT
ON library_db.reader
FROM 'lib_user1'@'localhost';
4.\u521b\u5efa\u89d2\u8272\u5e76\u6388\u6743
CREATE ROLE 'reader_role';
GRANT SELECT
ON library_db.*
TO 'reader_role';
CREATE USER 'lib_user2'@'localhost'
IDENTIFIED BY '123456';
GRANT 'reader_role'
TO 'lib_user2'@'localhost';
SET DEFAULT ROLE 'reader_role'
TO 'lib_user2'@'localhost';<\/pre>\n\n\n\n16.\u89c6\u56fe\u4e0e\u6d3e\u751f\u8868<\/h2>\n\n\n\n1.\u5e26\u805a\u5408\u51fd\u6570\u7684\u89c6\u56fe\uff1a\u7edf\u8ba1\u6bcf\u4e2a\u8bfb\u8005\u501f\u9605\u6b21\u6570
CREATE VIEW v_reader_borrow_count AS
SELECT r.rno, r.rname, COUNT(br.borrowid) AS borrow_count
FROM reader r
LEFT JOIN borrow br
ON r.rno = br.rno
GROUP BY r.rno, r.rname;
\u67e5\u8be2\uff1a
SELECT * FROM v_reader_borrow_count;
2.\u6d3e\u751f\u8868\uff1a\u67e5\u8be2\u501f\u9605\u6b21\u6570\u5927\u4e8e1\u7684\u8bfb\u8005
SELECT *
FROM (
SELECT rno, COUNT(*) AS borrow_count
FROM borrow
GROUP BY rno
) AS t
WHERE t.borrow_count > 1;
3.WITH \u5b50\u53e5\u7edf\u8ba1\u6bcf\u4f4d\u8bfb\u8005\u501f\u9605\u6570\u91cf
WITH reader_count AS (
SELECT rno, COUNT(*) AS total
FROM borrow
GROUP BY rno
)
SELECT r.rno, r.rname, rc.total
FROM reader r
LEFT JOIN reader_count rc
ON r.rno = rc.rno;
4.WITH \u5b50\u53e5\uff1a\u67e5\u8be2\u672a\u5f52\u8fd8\u56fe\u4e66
WITH unreturned AS (
SELECT br.borrowid, r.rname, b.bname,
br.borrowdate, br.returndate
FROM borrow br
JOIN reader r ON br.rno = r.rno
JOIN book b ON br.bno = b.bno
WHERE br.actualdate IS NULL
)
SELECT * FROM unreturned;<\/pre>\n\n\n\n17.\u6269\u5c55\u601d\u8003<\/h2>\n\n\n\n\n- \u5982\u4f55\u5904\u7406\u5206\u7c7b\u5b9e\u4f53\u7684\u81ea\u5173\u8054\uff1f<\/li>\n<\/ol>\n\n\n\n
\u5206\u7c7b\u5b9e\u4f53\u5b58\u5728\u201c\u4e0a\u7ea7\u5206\u7c7b\u201d\u548c\u201c\u4e0b\u7ea7\u5206\u7c7b\u201d\u7684\u5173\u7cfb\uff0c\u56e0\u6b64\u53ef\u4ee5\u5728 category \u8868\u4e2d\u8bbe\u7f6e parentid \u5b57\u6bb5\u3002
category(
cid,
cname,
parentid
)
\u5176\u4e2d cid \u662f\u5206\u7c7b\u7f16\u53f7\uff0cparentid \u662f\u4e0a\u7ea7\u5206\u7c7b\u7f16\u53f7\uff0c\u540c\u65f6 parentid \u4e5f\u662f\u6307\u5411 category.cid \u7684\u5916\u952e\u3002
\u5982\u679c\u67d0\u5206\u7c7b\u6ca1\u6709\u4e0a\u7ea7\u5206\u7c7b\uff0c\u5219 parentid \u53ef\u4ee5\u4e3a\u7a7a\u3002
\u8fd9\u79cd\u8bbe\u8ba1\u53ef\u4ee5\u8868\u793a\u6811\u5f62\u7ed3\u6784\uff0c\u4f8b\u5982\uff1a
\u56fe\u4e66
\u251c\u2500\u2500 \u8ba1\u7b97\u673a
\u2502 \u251c\u2500\u2500 \u6570\u636e\u5e93
\u2502 \u2514\u2500\u2500 \u7f51\u7edc\u6280\u672f
\u2514\u2500\u2500 \u6587\u5b66
\u2514\u2500\u2500 \u79d1\u5e7b\u5c0f\u8bf4<\/pre>\n\n\n\n
\n\n\n\n2. \u501f\u9605\u5173\u7cfb\u662f\u5426\u53ef\u80fd\u5b58\u5728\u6570\u636e\u5197\u4f59\uff1f<\/h2>\n\n\n\n\u501f\u9605\u8868\u5982\u679c\u53ea\u4fdd\u5b58 rno\u3001bno\u3001borrowdate\u3001returndate\u3001actualdate \u7b49\u4fe1\u606f\uff0c\u5219\u5197\u4f59\u8f83\u5c11\u3002
\u4f46\u662f\u5982\u679c\u5728 borrow \u8868\u4e2d\u540c\u65f6\u4fdd\u5b58\u8bfb\u8005\u59d3\u540d rname\u3001\u56fe\u4e66\u540d\u79f0 bname\u3001\u51fa\u7248\u793e press \u7b49\u4fe1\u606f\uff0c\u5c31\u4f1a\u4ea7\u751f\u6570\u636e\u5197\u4f59\u3002
\u4f8b\u5982\uff1a
borrow(borrowid, rno, rname, bno, bname, borrowdate)
\u5176\u4e2d rname \u4f9d\u8d56 rno\uff0cbname \u4f9d\u8d56 bno\uff0c\u800c\u4e0d\u662f\u76f4\u63a5\u4f9d\u8d56 borrowid\uff0c\u4f1a\u4ea7\u751f\u4f20\u9012\u4f9d\u8d56\u3002
\u89c4\u8303\u5316\u65b9\u6848\uff1a
\u5c06\u8bfb\u8005\u4fe1\u606f\u4fdd\u5b58\u5728 reader \u8868\uff1b
\u5c06\u56fe\u4e66\u4fe1\u606f\u4fdd\u5b58\u5728 book \u8868\uff1b
borrow \u8868\u53ea\u4fdd\u5b58\u8bfb\u8005\u8bc1\u53f7\u548c\u56fe\u4e66\u7f16\u53f7\u4f5c\u4e3a\u5916\u952e\u3002<\/pre>\n\n\n\n
\n\n\n\n3. \u5982\u4f55\u9632\u6b62\u5e93\u5b58\u4e3a\u8d1f\u6570\uff1f<\/h2>\n\n\n\n\u53ef\u4ee5\u4ece\u4e24\u4e2a\u65b9\u9762\u9632\u6b62\u5e93\u5b58\u4e3a\u8d1f\u6570\uff1a
\u7b2c\u4e00\uff0c\u5728 book \u8868\u4e2d\u8bbe\u7f6e CHECK(stock >= 0) \u7ea6\u675f\uff0c\u4fdd\u8bc1\u5e93\u5b58\u4e0d\u80fd\u5c0f\u4e8e0\u3002
\u7b2c\u4e8c\uff0c\u5728\u501f\u4e66\u89e6\u53d1\u5668\u4e2d\u5224\u65ad\u5e93\u5b58\u6570\u91cf\u3002
\u5f53\u63d2\u5165 borrow \u501f\u9605\u8bb0\u5f55\u65f6\uff0c\u5148\u67e5\u8be2\u56fe\u4e66\u5e93\u5b58\u3002
\u5982\u679c\u5e93\u5b58\u5c0f\u4e8e\u7b49\u4e8e0\uff0c\u5219\u4f7f\u7528 SIGNAL \u629b\u51fa\u9519\u8bef\uff0c\u963b\u6b62\u501f\u4e66\u64cd\u4f5c\uff1b
\u5982\u679c\u5e93\u5b58\u5927\u4e8e0\uff0c\u5219\u5141\u8bb8\u501f\u9605\uff0c\u5e76\u81ea\u52a8\u5c06\u5e93\u5b58\u51cf1\u3002
\u8fd9\u6837\u53ef\u4ee5\u4fdd\u8bc1\u501f\u4e66\u65f6\u4e0d\u4f1a\u51fa\u73b0\u5e93\u5b58\u4e3a\u8d1f\u6570\u7684\u60c5\u51b5\u3002<\/pre>\n\n\n\n
\n\n\n\n4. \u9884\u7ea6\u56fe\u4e66\u529f\u80fd\u9700\u8981\u589e\u52a0\u54ea\u4e9b\u5b9e\u4f53\u548c\u5173\u7cfb\uff1f<\/h2>\n\n\n\n\u5982\u679c\u7cfb\u7edf\u652f\u6301\u9884\u7ea6\u56fe\u4e66\u529f\u80fd\uff0c\u53ef\u4ee5\u589e\u52a0 reservation \u9884\u7ea6\u8868\u3002
reservation(
reserveid,
rno,
bno,
reservedate,
status
)
\u5176\u4e2d\uff1a
reserveid \u8868\u793a\u9884\u7ea6\u7f16\u53f7\uff1b
rno \u662f\u8bfb\u8005\u8bc1\u53f7\uff0c\u5916\u952e\u5f15\u7528 reader.rno\uff1b
bno \u662f\u56fe\u4e66\u7f16\u53f7\uff0c\u5916\u952e\u5f15\u7528 book.bno\uff1b
reservedate \u8868\u793a\u9884\u7ea6\u65e5\u671f\uff1b
status \u8868\u793a\u9884\u7ea6\u72b6\u6001\uff0c\u5982\u201c\u9884\u7ea6\u4e2d\u201d\u201c\u5df2\u53d6\u6d88\u201d\u201c\u5df2\u5b8c\u6210\u201d\u3002
\u65b0\u589e\u5173\u7cfb\uff1a
\u4e00\u4e2a\u8bfb\u8005\u53ef\u4ee5\u9884\u7ea6\u591a\u672c\u56fe\u4e66\uff1b
\u4e00\u672c\u56fe\u4e66\u53ef\u4ee5\u88ab\u591a\u4e2a\u8bfb\u8005\u9884\u7ea6\uff1b
\u8bfb\u8005\u548c\u56fe\u4e66\u4e4b\u95f4\u901a\u8fc7 reservation \u8868\u5f62\u6210 m:n \u8054\u7cfb\u3002<\/pre>\n\n\n\n
\n\n\n\n5. \u4e3a\u4ec0\u4e48\u9075\u5faa\u6700\u5c0f\u6743\u9650\u539f\u5219\uff1f<\/h2>\n\n\n\n\u6700\u5c0f\u6743\u9650\u539f\u5219\u662f\u6307\u53ea\u7ed9\u7528\u6237\u5b8c\u6210\u5de5\u4f5c\u6240\u5fc5\u9700\u7684\u6743\u9650\uff0c\u4e0d\u6388\u4e88\u591a\u4f59\u6743\u9650\u3002
\u5728\u672c\u5b9e\u9a8c\u4e2d\uff0c\u5982\u679c\u67d0\u7528\u6237\u53ea\u8d1f\u8d23\u67e5\u8be2\u56fe\u4e66\u4fe1\u606f\uff0c\u5219\u53ea\u6388\u4e88 SELECT \u6743\u9650\u5373\u53ef\uff0c\u4e0d\u5e94\u8be5\u6388\u4e88 INSERT\u3001UPDATE\u3001DELETE \u7b49\u6743\u9650\u3002
\u4f8b\u5982\uff1a
GRANT SELECT ON library_db.book TO 'lib_user1'@'localhost';
\u8fd9\u6837\u53ef\u4ee5\u9632\u6b62\u7528\u6237\u8bef\u5220\u3001\u8bef\u6539\u6570\u636e\uff0c\u63d0\u9ad8\u6570\u636e\u5e93\u5b89\u5168\u6027\u3002
\u5982\u679c\u540e\u7eed\u4e0d\u518d\u9700\u8981\u67d0\u9879\u6743\u9650\uff0c\u8fd8\u53ef\u4ee5\u4f7f\u7528 REVOKE \u56de\u6536\u6743\u9650\u3002<\/pre>\n\n\n\n
\n\n\n\n6. \u5e76\u53d1\u501f\u9605\u5e93\u5b58\u4ec5\u52691\u672c\u7684\u56fe\u4e66\u4f1a\u4ea7\u751f\u4ec0\u4e48\u95ee\u9898\uff1f\u5982\u4f55\u89e3\u51b3\uff1f<\/h2>\n\n\n\n\u5f53\u591a\u7528\u6237\u540c\u65f6\u501f\u9605\u540c\u4e00\u672c\u5e93\u5b58\u4ec5\u52691\u672c\u7684\u56fe\u4e66\u65f6\uff0c\u53ef\u80fd\u51fa\u73b0\u8d85\u5356\u95ee\u9898\u3002
\u4f8b\u5982\u4e24\u4e2a\u7528\u6237\u540c\u65f6\u8bfb\u53d6\u5e93\u5b58 stock=1\uff0c\u90fd\u8ba4\u4e3a\u53ef\u4ee5\u501f\u9605\uff0c\u7136\u540e\u540c\u65f6\u63d2\u5165\u501f\u9605\u8bb0\u5f55\u5e76\u6267\u884c\u5e93\u5b58\u51cf1\uff0c\u6700\u7ec8\u53ef\u80fd\u5bfc\u81f4\u5e93\u5b58\u5f02\u5e38\u6216\u51fa\u73b0\u8d85\u989d\u501f\u9605\u3002
\u89e3\u51b3\u65b9\u6cd5\uff1a
1. \u4f7f\u7528\u4e8b\u52a1\u4fdd\u8bc1\u501f\u4e66\u64cd\u4f5c\u7684\u539f\u5b50\u6027\uff1b
2. \u4f7f\u7528 SELECT ... FOR UPDATE \u5bf9\u56fe\u4e66\u5e93\u5b58\u8bb0\u5f55\u52a0\u884c\u7ea7\u9501\uff1b
3. \u5728\u89e6\u53d1\u5668\u4e2d\u5224\u65ad\u5e93\u5b58\u662f\u5426\u5927\u4e8e0\uff1b
4. \u7ed9 stock \u5b57\u6bb5\u8bbe\u7f6e CHECK(stock >= 0) \u7ea6\u675f\u3002
\u793a\u4f8b\uff1a
START TRANSACTION;
SELECT stock
FROM book
WHERE bno='B001'
FOR UPDATE;
UPDATE book
SET stock = stock - 1
WHERE bno='B001'
AND stock > 0;
INSERT INTO borrow(rno,bno,borrowdate,returndate)
VALUES('R2024001','B001','2025-05-01','2025-05-15');
COMMIT;
\u8fd9\u6837\u53ef\u4ee5\u907f\u514d\u591a\u4e2a\u7528\u6237\u540c\u65f6\u4fee\u6539\u5e93\u5b58\u5bfc\u81f4\u6570\u636e\u4e0d\u4e00\u81f4\u3002<\/pre>\n\n\n\n
\n\n\n\n\u5b9e\u9a8c\u603b\u7ed3<\/h1>\n\n\n\n \u901a\u8fc7\u672c\u6b21\u56fe\u4e66\u501f\u9605\u7ba1\u7406\u7cfb\u7edf\u7efc\u5408\u5b9e\u9a8c\uff0c\u6211\u7cfb\u7edf\u5730\u5b8c\u6210\u4e86\u6570\u636e\u5e93\u8bbe\u8ba1\u4e0e\u5b9e\u73b0\u7684\u5168\u8fc7\u7a0b\u3002\u5b9e\u9a8c\u4ece\u9700\u6c42\u5206\u6790\u5f00\u59cb\uff0c\u9010\u6b65\u5b8c\u6210 E-R \u56fe\u8bbe\u8ba1\u3001\u5173\u7cfb\u6a21\u5f0f\u8f6c\u6362\u3001\u7269\u7406\u8868\u7ed3\u6784\u8bbe\u8ba1\u3001\u6570\u636e\u63d2\u5165\u3001\u67e5\u8be2\u64cd\u4f5c\u3001\u89c6\u56fe\u3001\u7d22\u5f15\u3001\u5b8c\u6574\u6027\u7ea6\u675f\u3001\u89e6\u53d1\u5668\u548c\u6743\u9650\u7ba1\u7406\u7b49\u5185\u5bb9\uff0c\u4f7f\u6211\u5bf9\u6570\u636e\u5e93\u5e94\u7528\u7cfb\u7edf\u7684\u8bbe\u8ba1\u6d41\u7a0b\u6709\u4e86\u66f4\u52a0\u5b8c\u6574\u7684\u8ba4\u8bc6\u3002
\u200b
\u5728\u5b9e\u9a8c\u8fc7\u7a0b\u4e2d\uff0c\u6211\u9996\u5148\u6839\u636e\u56fe\u4e66\u9986\u4e1a\u52a1\u9700\u6c42\u5206\u6790\u51fa\u56fe\u4e66\u3001\u8bfb\u8005\u3001\u501f\u9605\u3001\u51fa\u7248\u793e\u3001\u5206\u7c7b\u7b49\u5b9e\u4f53\uff0c\u5e76\u660e\u786e\u4e86\u5b83\u4eec\u4e4b\u95f4\u7684\u8054\u7cfb\u7c7b\u578b\u3002\u4f8b\u5982\uff0c\u51fa\u7248\u793e\u4e0e\u56fe\u4e66\u4e4b\u95f4\u662f\u4e00\u5bf9\u591a\u5173\u7cfb\uff0c\u5206\u7c7b\u4e0e\u56fe\u4e66\u4e4b\u95f4\u662f\u4e00\u5bf9\u591a\u5173\u7cfb\uff0c\u8bfb\u8005\u4e0e\u56fe\u4e66\u4e4b\u95f4\u901a\u8fc7\u501f\u9605\u8868\u5f62\u6210\u591a\u5bf9\u591a\u5173\u7cfb\u3002\u901a\u8fc7 E-R \u56fe\u8bbe\u8ba1\uff0c\u6211\u8fdb\u4e00\u6b65\u7406\u89e3\u4e86\u6982\u5ff5\u7ed3\u6784\u8bbe\u8ba1\u5728\u6570\u636e\u5e93\u5f00\u53d1\u4e2d\u7684\u91cd\u8981\u4f5c\u7528\u3002
\u200b
\u5728\u903b\u8f91\u7ed3\u6784\u8bbe\u8ba1\u9636\u6bb5\uff0c\u6211\u5c06 E-R \u56fe\u8f6c\u6362\u4e3a\u5173\u7cfb\u6a21\u5f0f\uff0c\u5e76\u5206\u6790\u5404\u8868\u662f\u5426\u6ee1\u8db3\u7b2c\u4e09\u8303\u5f0f\u3002\u901a\u8fc7\u89c4\u8303\u5316\u8bbe\u8ba1\uff0c\u907f\u514d\u4e86\u5728\u501f\u9605\u8868\u4e2d\u91cd\u590d\u4fdd\u5b58\u8bfb\u8005\u59d3\u540d\u3001\u56fe\u4e66\u540d\u79f0\u7b49\u4fe1\u606f\uff0c\u51cf\u5c11\u4e86\u6570\u636e\u5197\u4f59\uff0c\u63d0\u9ad8\u4e86\u6570\u636e\u4e00\u81f4\u6027\u3002\u5728\u7269\u7406\u8bbe\u8ba1\u9636\u6bb5\uff0c\u6211\u4f7f\u7528 SQL \u521b\u5efa\u6570\u636e\u5e93\u548c\u6570\u636e\u8868\uff0c\u8bbe\u7f6e\u4e86\u4e3b\u952e\u3001\u5916\u952e\u3001\u975e\u7a7a\u3001\u9ed8\u8ba4\u503c\u548c CHECK \u7ea6\u675f\uff0c\u5bf9\u5b9e\u4f53\u5b8c\u6574\u6027\u3001\u53c2\u7167\u5b8c\u6574\u6027\u548c\u7528\u6237\u5b9a\u4e49\u5b8c\u6574\u6027\u6709\u4e86\u66f4\u6df1\u523b\u7684\u7406\u89e3\u3002
\u200b
\u5728\u6570\u636e\u64cd\u4f5c\u90e8\u5206\uff0c\u6211\u7ec3\u4e60\u4e86 INSERT\u3001UPDATE\u3001DELETE \u548c SELECT \u8bed\u53e5\uff0c\u5e76\u5b8c\u6210\u4e86\u57fa\u7840\u67e5\u8be2\u3001\u805a\u5408\u67e5\u8be2\u3001\u591a\u8868\u8fde\u63a5\u67e5\u8be2\u3001\u5d4c\u5957\u67e5\u8be2\u548c\u96c6\u5408\u67e5\u8be2\u7b49\u5185\u5bb9\u3002\u901a\u8fc7\u8fd9\u4e9b\u7ec3\u4e60\uff0c\u6211\u638c\u63e1\u4e86 SQL \u67e5\u8be2\u8bed\u53e5\u7684\u5e38\u89c1\u5199\u6cd5\uff0c\u5c24\u5176\u662f\u591a\u8868\u8fde\u63a5\u548c\u5d4c\u5957\u67e5\u8be2\u7684\u4f7f\u7528\u65b9\u6cd5\u3002\u5b9e\u9a8c\u4e2d\u8fd8\u521b\u5efa\u4e86\u89c6\u56fe\u548c\u7d22\u5f15\uff0c\u7406\u89e3\u4e86\u89c6\u56fe\u53ef\u4ee5\u7b80\u5316\u590d\u6742\u67e5\u8be2\uff0c\u7d22\u5f15\u53ef\u4ee5\u63d0\u9ad8\u67e5\u8be2\u6548\u7387\uff0c\u4f46\u4e5f\u4f1a\u589e\u52a0\u7ef4\u62a4\u6210\u672c\u3002
\u200b
\u5728\u89e6\u53d1\u5668\u90e8\u5206\uff0c\u6211\u5b9e\u73b0\u4e86\u501f\u4e66\u81ea\u52a8\u51cf\u5c11\u5e93\u5b58\u3001\u8fd8\u4e66\u81ea\u52a8\u589e\u52a0\u5e93\u5b58\u5e76\u8ba1\u7b97\u7f5a\u6b3e\u3001\u5220\u9664\u8bfb\u8005\u524d\u8bb0\u5f55\u65e5\u5fd7\u7b49\u529f\u80fd\u3002\u901a\u8fc7\u89e6\u53d1\u5668\u5b9e\u9a8c\uff0c\u6211\u8ba4\u8bc6\u5230\u6570\u636e\u5e93\u4e0d\u4ec5\u53ef\u4ee5\u5b58\u50a8\u6570\u636e\uff0c\u8fd8\u53ef\u4ee5\u5728\u7279\u5b9a\u64cd\u4f5c\u53d1\u751f\u65f6\u81ea\u52a8\u6267\u884c\u4e00\u4e9b\u4e1a\u52a1\u903b\u8f91\u3002\u5b9e\u9a8c\u8fc7\u7a0b\u4e2d\u4e5f\u9047\u5230\u4e86\u4e00\u4e9b\u95ee\u9898\uff0c\u4f8b\u5982\u5916\u952e\u7ea6\u675f\u5bfc\u81f4\u6570\u636e\u65e0\u6cd5\u5220\u9664\u3001CHECK \u7ea6\u675f\u63d2\u5165\u5931\u8d25\u3001\u89e6\u53d1\u5668\u8bed\u6cd5\u9519\u8bef\u7b49\u3002\u901a\u8fc7\u67e5\u770b\u9519\u8bef\u4fe1\u606f\u3001\u4fee\u6539 SQL \u8bed\u53e5\u548c\u53cd\u590d\u6d4b\u8bd5\uff0c\u6700\u7ec8\u89e3\u51b3\u4e86\u8fd9\u4e9b\u95ee\u9898\u3002
\u200b
\u901a\u8fc7\u672c\u6b21\u5b9e\u9a8c\uff0c\u6211\u4e0d\u4ec5\u5de9\u56fa\u4e86\u6570\u636e\u5e93\u7406\u8bba\u77e5\u8bc6\uff0c\u4e5f\u63d0\u9ad8\u4e86 SQL \u7f16\u5199\u80fd\u529b\u548c\u6570\u636e\u5e93\u8c03\u8bd5\u80fd\u529b\u3002\u4eca\u540e\u5728\u8bbe\u8ba1\u6570\u636e\u5e93\u7cfb\u7edf<\/pre>\n","protected":false},"excerpt":{"rendered":"\u6570\u636e\u5e93\u7efc\u5408\u5b9e\u9a8c 1.\u9700\u6c42\u5206\u6790 \u67d0\u5927\u578b\u56fe\u4e66\u9986\u9700\u8981\u5f00\u53d1\u4e00\u5957\u6570\u5b57\u5316\u501f\u9605\u7ba1\u7406\u7cfb\u7edf\uff0c\u4e3b\u8981\u4e1a\u52a1\u9700\u6c42\u5982\u4e0b\uff1a \u56fe\u4e66\u4fe1\u606f\uff1a\u8bb0\u5f55\u56fe […]<\/p>\n","protected":false},"author":1,"featured_media":448,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[9],"tags":[],"class_list":["post-446","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-wenzhang"],"_links":{"self":[{"href":"https:\/\/fg2025.cn\/index.php\/wp-json\/wp\/v2\/posts\/446","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/fg2025.cn\/index.php\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/fg2025.cn\/index.php\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/fg2025.cn\/index.php\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/fg2025.cn\/index.php\/wp-json\/wp\/v2\/comments?post=446"}],"version-history":[{"count":0,"href":"https:\/\/fg2025.cn\/index.php\/wp-json\/wp\/v2\/posts\/446\/revisions"}],"wp:attachment":[{"href":"https:\/\/fg2025.cn\/index.php\/wp-json\/wp\/v2\/media?parent=446"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/fg2025.cn\/index.php\/wp-json\/wp\/v2\/categories?post=446"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/fg2025.cn\/index.php\/wp-json\/wp\/v2\/tags?post=446"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}
bno CHAR(10) PRIMARY KEY,
bname VARCHAR(50) NOT NULL,
author VARCHAR(30),
press VARCHAR(30),
pubyear INT,
stock INT DEFAULT 1 CHECK(stock>=0)
);
CREATE TABLE reader(
rno CHAR(12) PRIMARY KEY,
rname VARCHAR(20) NOT NULL,
rsex CHAR(1)
CHECK(rsex IN('\u7537','\u5973')),
dept VARCHAR(40),
phone VARCHAR(20)
);
CREATE TABLE borrow(
borrowid INT AUTO_INCREMENT PRIMARY KEY,
rno CHAR(12) NOT NULL,
bno CHAR(10) NOT NULL,
borrowdate DATE NOT NULL,
returndate DATE NOT NULL,
actualdate DATE,
CONSTRAINT fk_reader
FOREIGN KEY(rno)
REFERENCES reader(rno)
ON DELETE RESTRICT
ON UPDATE CASCADE,
CONSTRAINT fk_book
FOREIGN KEY(bno)
REFERENCES book(bno)
ON DELETE RESTRICT
ON UPDATE CASCADE
);
desc book;
desc reader;
desc borrow;<\/pre>\n\n\n\n
3.3 \u6dfb\u52a0\u4fee\u6539\u5220\u9664\u5b57\u6bb5<\/h3>\n\n\n\n ALTER TABLE book
ADD pages INT;
\u200b
ALTER TABLE reader
ADD email VARCHAR(50) UNIQUE;
\u200b
\u9a8c\u8bc1\uff1a
desc book
desc reader
\u200b
ALTER TABLE book
MODIFY author VARCHAR(50);
\u200b
ALTER TABLE reader
MODIFY phone VARCHAR(20)
DEFAULT '\u65e0';
\u200b
SHOW CREATE TABLE borrow;
ALTER TABLE book
DROP COLUMN pages;
\u200b
ALTER TABLE borrow
DROP FOREIGN KEY fk_reader;<\/pre>\n\n\n\n4.\u6570\u636e\u63d2\u5165<\/h2>\n\n\n\n INSERT INTO book VALUES
('B001','\u6570\u636e\u5e93\u7cfb\u7edf\u6982\u8bba','\u738b\u73ca',
'\u9ad8\u7b49\u6559\u80b2\u51fa\u7248\u793e',2018,5),
\u200b
('B002','C\u7a0b\u5e8f\u8bbe\u8ba1\u8bed\u8a00','K&R',
'\u673a\u68b0\u5de5\u4e1a\u51fa\u7248\u793e',2015,3),
\u200b
('B003','\u4e09\u4f53','\u5218\u6148\u6b23',
'\u91cd\u5e86\u51fa\u7248\u793e',2010,8),
\u200b
('B004','\u8ba1\u7b97\u673a\u7f51\u7edc','\u8c22\u5e0c\u4ec1',
'\u7535\u5b50\u5de5\u4e1a\u51fa\u7248\u793e',2018,4);
\u200b
INSERT INTO reader
VALUES
('R2024001','\u5f20\u660e','\u7537',
'\u8ba1\u7b97\u673a\u5b66\u9662','13812345678',
'zhangming@qq.com'),
\u200b
('R2024002','\u674e\u82b3','\u5973',
'\u4fe1\u606f\u5b66\u9662','13912345678',
'lifang@qq.com'),
\u200b
('R2024003','\u738b\u78ca','\u7537',
'\u6587\u5b66\u9662','13612345678',
'wanglei@qq.com');
\u200b
INSERT INTO borrow VALUES
(1,'R2024001','B001',
'2025-03-01',
'2025-03-15',
'2025-03-14'),
(2,'R2024001','B003',
'2025-03-10',
'2025-03-24',
NULL),
(3,'R2024002','B002',
'2025-04-01',
'2025-04-15',
NULL),
(4,'R2024003','B004',
'2025-03-20',
'2025-04-03',
'2025-04-05');<\/pre>\n\n\n\n4.1 \u8bbe\u8ba1\u8fdd\u53cd\u5916\u952e\u7ea6\u675f\u548ccheck\u7ea6\u675f\u5e76\u89e3\u91ca<\/h3>\n\n\n\n INSERT INTO borrow(
rno,bno,
borrowdate,
returndate)
VALUES(
'R999999',
'B001',
'2025-05-01',
'2025-05-15');
\u200b
\u9519\u8bef\uff1aCannot add or update a child row:
a foreign key constraint fails
\u200b
\u539f\u56e0\uff1aR999999\u5728reader\u8868\u4e2d\u4e0d\u5b58\u5728\uff0c
\u8fdd\u53cd\u53c2\u7167\u5b8c\u6574\u6027\u7ea6\u675f\u3002
\u200b
\u8fdd\u53cdcheck
INSERT INTO reader
VALUES(
'R2024004',
'\u8d75\u654f',
'\u672a\u77e5',
'\u827a\u672f\u5b66\u9662',
'13712345678');
\u200b
\u9519\u8bef\uff1aCheck constraint violated
\u200b
\u539f\u56e0\uff1arsex\u5b57\u6bb5\u53ea\u80fd\u53d6
\u7537 \u6216 \u5973\uff0c
\u56e0\u6b64\u8fdd\u53cdCHECK\u7ea6\u675f\u3002<\/pre>\n\n\n\n5.\u6570\u636e\u67e5\u8be2\uff08DQL-\u57fa\u7840\u67e5\u8be2\uff09<\/h2>\n\n\n\n 1.select\u67e5\u8be2\u5168\u90e8\u56fe\u4e66\u4fe1\u606f
select * from book;
2.\u67e5\u8be2\u5e93\u5b58\u5927\u4e8e3\u7684\u56fe\u4e66
SELECT bno,bname,stock
FROM book
WHERE stock > 3;
3.\u67e5\u8be22018\u5e74\u51fa\u7248\u4e14\u5e93\u5b58\u4e0d\u5c11\u4e8e4\u672c\u7684\u56fe\u4e66
SELECT bno,bname,pubyear,stock
FROM book
WHERE pubyear = 2018 AND stock >= 4;
4.\u67e5\u8be22015\u5e74\u81f32018\u5e74\u51fa\u7248\u7684\u56fe\u4e66
SELECT bno,bname,pubyear
FROM book
WHERE pubyear BETWEEN 2015 AND 2018;
5.\u67e5\u8be2\u51fa\u7248\u793e\u4e3a\u201c\u91cd\u5e86\u51fa\u7248\u793e\u201d\u6216\u201c\u9ad8\u7b49\u6559\u80b2\u51fa\u7248\u793e\u201d\u7684\u56fe\u4e66
SELECT bno,bname,press
FROM book
WHERE press IN('\u91cd\u5e86\u51fa\u7248\u793e','\u9ad8\u7b49\u6559\u80b2\u51fa\u7248\u793e');
6.\u67e5\u8be2\u4e66\u540d\u4e2d\u5305\u542b\u201c\u8ba1\u7b97\u673a\u201d\u7684\u56fe\u4e66
SELECT bno,bname
FROM book
WHERE bname LIKE '%\u8ba1\u7b97\u673a%';
7.\u67e5\u8be2\u5c1a\u672a\u5f52\u8fd8\u7684\u501f\u9605\u8bb0\u5f55
SELECT *
FROM borrow
WHERE actualdate IS NULL;
8.\u6309\u5e93\u5b58\u6570\u91cf\u964d\u5e8f\u67e5\u8be2\u56fe\u4e66
SELECT bno,bname,stock
FROM book
ORDER BY stock DESC;
9.\u67e5\u8be2\u5e93\u5b58\u6700\u591a\u7684\u524d2\u672c\u56fe\u4e66
SELECT bno,bname,stock
FROM book
ORDER BY stock DESC
LIMIT 2;
10.\u67e5\u8be2\u6240\u6709\u4e0d\u540c\u7684\u51fa\u7248\u793e
SELECT DISTINCT press
FROM book;<\/pre>\n\n\n\n6.\u6570\u636e\u66f4\u65b0\uff08update\/delete\uff09<\/h2>\n\n\n\n 1.\u5c06BOO1\u7684\u5e93\u5b58\u4fee\u6539\u4e3a6
UPDATE book
SET stock = 6
WHERE bno = 'B001';
\u200b
SELECT * FROM book WHERE bno='B001';
2.\u4fee\u6539\u5f20\u660e\u7684\u9662\u7cfb\u548c\u7535\u8bdd
UPDATE reader
SET dept = '\u4eba\u5de5\u667a\u80fd\u5b66\u9662',
phone = '18888888888'
WHERE rno = 'R2024001';
\u200b
SELECT * FROM reader WHERE rno='R2024001';
3.\u5c062018\u5e74\u51fa\u7248\u56fe\u4e66\u5e93\u5b58\u7edf\u4e00\u589e\u52a01
UPDATE book
SET stock = stock + 1
WHERE pubyear = 2018;
\u200b
SELECT * FROM book WHERE pubyear=2018;
4.\u5220\u9664\u4e00\u4e2a\u6d4b\u8bd5\u8bfb\u8005
INSERT INTO reader
VALUES('R2024999','\u6d4b\u8bd5\u8bfb\u8005','\u7537','\u6d4b\u8bd5\u5b66\u9662','\u65e0');
\u200b
DELETE FROM reader
WHERE rno = 'R2024999';
5.\u4e8b\u52a1\u63a7\u5236\uff1a\u66f4\u65b0\u540e\u56de\u6eda
START TRANSACTION;
\u200b
UPDATE book
SET stock = stock - 1
WHERE bno = 'B003';
\u200b
SELECT * FROM book WHERE bno='B003';
\u200b
ROLLBACK;
\u200b
SELECT * FROM book WHERE bno='B003';<\/pre>\n\n\n\n7.\u805a\u5408\u67e5\u8be2\u4e0e\u5206\u7ec4\u7edf\u8ba1<\/h2>\n\n\n\n 1.\u7edf\u8ba1\u56fe\u4e66\u603b\u6570
select count(*) as \u56fe\u4e66\u603b\u6570 from book;
2.\u7edf\u8ba1\u56fe\u4e66\u5e93\u5b58\u603b\u91cf
select sum(stock) as \u5e93\u5b58\u603b\u91cf from book;
3.\u7edf\u8ba1\u5e73\u5747\u5e93\u5b58
select avg(stock) as \u5e73\u5747\u5e93\u5b58 from book;
4.\u67e5\u8be2\u6700\u5927\u5e93\u5b58\u548c\u6700\u5c0f\u5e93\u5b58
SELECT MAX(stock) AS \u6700\u5927\u5e93\u5b58,
MIN(stock) AS \u6700\u5c0f\u5e93\u5b58
FROM book;
5.\u6309\u51fa\u7248\u793e\u7edf\u8ba1\u56fe\u4e66\u6570\u91cf\uff0c\u5e76\u7b5b\u9009\u6570\u91cf\u5927\u4e8e\u7b49\u4e8e1\u7684\u51fa\u7248\u793e
SELECT press, COUNT(*) AS \u56fe\u4e66\u6570\u91cf
FROM book
GROUP BY press
HAVING COUNT(*) >= 1;<\/pre>\n\n\n\n8.\u591a\u8868\u8fde\u63a5\u67e5\u8be2<\/h2>\n\n\n\n1.\u7b49\u503c\u8fde\u63a5\uff1a\u67e5\u8be2\u8bfb\u8005\u59d3\u540d\u548c\u6240\u501f\u56fe\u4e66
SELECT reader.rname, book.bname
FROM reader, borrow, book
WHERE reader.rno = borrow.rno
AND borrow.bno = book.bno;
2.\u5185\u8fde\u63a5\uff1a\u67e5\u8be2\u501f\u9605\u8bb0\u5f55\u8be6\u60c5
SELECT r.rname, b.bname, br.borrowdate, br.returndate
FROM borrow br
JOIN reader r ON br.rno = r.rno
JOIN book b ON br.bno = b.bno;
3.\u5de6\u5916\u8fde\u63a5\uff1a\u67e5\u8be2\u6240\u6709\u8bfb\u8005\u53ca\u5176\u501f\u9605\u8bb0\u5f55
SELECT r.rno, r.rname, br.borrowid, br.bno
FROM reader r
LEFT JOIN borrow br
ON r.rno = br.rno;
4.\u53f3\u5916\u8fde\u63a5\uff1a\u67e5\u8be2\u6240\u6709\u501f\u9605\u8bb0\u5f55\u53ca\u8bfb\u8005\u4fe1\u606f
SELECT r.rname, br.borrowid, br.bno
FROM reader r
RIGHT JOIN borrow br
ON r.rno = br.rno;
5.\u81ea\u8eab\u8fde\u63a5\uff1a\u67e5\u8be2\u540c\u4e00\u5e74\u51fa\u7248\u7684\u4e0d\u540c\u56fe\u4e66
SELECT a.bname AS \u56fe\u4e661,
b.bname AS \u56fe\u4e662,
a.pubyear AS \u51fa\u7248\u5e74\u4efd
FROM book a
JOIN book b
ON a.pubyear = b.pubyear
AND a.bno < b.bno;<\/pre>\n\n\n\n9.\u5d4c\u5957\u67e5\u8be2<\/h2>\n\n\n\n1.IN\uff1a\u67e5\u8be2\u501f\u8fc7\u4e66\u7684\u8bfb\u8005
SELECT *
FROM reader
WHERE rno IN(
SELECT rno FROM borrow
);
2.\u6bd4\u8f83\u8fd0\u7b97\u7b26\uff1a\u67e5\u8be2\u5e93\u5b58\u5927\u4e8e\u5e73\u5747\u5e93\u5b58\u7684\u56fe\u4e66
SELECT bno,bname,stock
FROM book
WHERE stock > (
SELECT AVG(stock)
FROM book
);
3.EXISTS\uff1a\u67e5\u8be2\u5b58\u5728\u501f\u9605\u8bb0\u5f55\u7684\u8bfb\u8005
SELECT *
FROM reader r
WHERE EXISTS(
SELECT *
FROM borrow br
WHERE br.rno = r.rno
);
4.ANY\uff1a\u67e5\u8be2\u5e93\u5b58\u5927\u4e8e\u4efb\u610f\u4e00\u672c2018\u5e74\u51fa\u7248\u56fe\u4e66\u5e93\u5b58\u7684\u56fe\u4e66
SELECT bno,bname,stock
FROM book
WHERE stock > ANY(
SELECT stock
FROM book
WHERE pubyear = 2018
);
5.ALL\uff1a\u67e5\u8be2\u5e93\u5b58\u4e0d\u5c11\u4e8e\u6240\u6709\u56fe\u4e66\u5e93\u5b58\u7684\u56fe\u4e66
SELECT bno,bname,stock
FROM book
WHERE stock >= ALL(
SELECT stock
FROM book
);<\/pre>\n\n\n\n10.\u96c6\u5408\u67e5\u8be2<\/h2>\n\n\n\n1.UNION\uff1a\u5408\u5e76\u8bfb\u8005\u59d3\u540d\u548c\u4f5c\u8005\u59d3\u540d\u5e76\u53bb\u91cd
SELECT rname AS name
FROM reader
UNION
SELECT author AS name
FROM book;
2.UNION ALL\uff1a\u5408\u5e76\u8bfb\u8005\u59d3\u540d\u548c\u4f5c\u8005\u59d3\u540d\uff0c\u4e0d\u53bb\u91cd
SELECT rname AS name
FROM reader
UNION ALL
SELECT author AS name
FROM book;
3.\u6a21\u62df INTERSECT\uff1a\u67e5\u8be2\u501f\u8fc7\u4e66\u7684\u8bfb\u8005\u8bc1\u53f7
SELECT rno
FROM reader
WHERE rno IN(
SELECT rno
FROM borrow
);
4.\u6a21\u62df EXCEPT\uff1a\u67e5\u8be2\u6ca1\u6709\u501f\u4e66\u7684\u8bfb\u8005
SELECT rno,rname
FROM reader
WHERE rno NOT IN(
SELECT rno
FROM borrow
);<\/pre>\n\n\n\n11.\u89c6\u56fe\u64cd\u4f5c<\/h2>\n\n\n\n1.\u521b\u5efa\u672a\u5f52\u8fd8\u56fe\u4e66\u89c6\u56fe
CREATE VIEW v_unreturned AS
SELECT br.borrowid, r.rname, b.bname,
br.borrowdate, br.returndate
FROM borrow br
JOIN reader r ON br.rno = r.rno
JOIN book b ON br.bno = b.bno
WHERE br.actualdate IS NULL;
2.\u67e5\u8be2\u89c6\u56fe
SELECT * FROM v_unreturned;
3.\u521b\u5efa\u5b66\u751f\u8bfb\u8005\u89c6\u56fe\uff0c\u5e26 WITH CHECK OPTION
CREATE VIEW v_student_reader AS
SELECT *
FROM reader
WHERE dept LIKE '%\u5b66\u9662%'
WITH CHECK OPTION;
4.\u6d4b\u8bd5\u53ef\u66f4\u65b0\u89c6\u56fe
UPDATE v_student_reader
SET phone = '18800000000'
WHERE rno = 'R2024002';
\u8bf4\u660e\uff1a
\u8be5\u89c6\u56fe\u57fa\u4e8e\u5355\u8868 reader \u521b\u5efa\uff0c\u6ca1\u6709\u805a\u5408\u51fd\u6570\u3001\u5206\u7ec4\u548c\u8fde\u63a5\uff0c\u56e0\u6b64\u5c5e\u4e8e\u53ef\u66f4\u65b0\u89c6\u56fe\u3002
5.\u521b\u5efa\u4e0d\u53ef\u66f4\u65b0\u7684\u805a\u5408\u89c6\u56fe
CREATE VIEW v_press_count AS
SELECT press, COUNT(*) AS total
FROM book
GROUP BY press;
\u8bf4\u660e\uff1a
\u8be5\u89c6\u56fe\u4f7f\u7528\u4e86 GROUP BY \u548c COUNT \u805a\u5408\u51fd\u6570\uff0c\u56e0\u6b64\u4e00\u822c\u4e0d\u80fd\u76f4\u63a5\u66f4\u65b0\u3002
6.\u5220\u9664\u89c6\u56fe
DROP VIEW v_unreturned;
DROP VIEW v_student_reader;
DROP VIEW v_press_count;<\/pre>\n\n\n\n12.\u7d22\u5f15<\/h2>\n\n\n\n1.\u521b\u5efa\u666e\u901a\u7d22\u5f15
CREATE INDEX idx_book_bname
ON book(bname);
2.\u521b\u5efa\u552f\u4e00\u7d22\u5f15
CREATE UNIQUE INDEX idx_reader_phone
ON reader(phone);
3.\u521b\u5efa\u590d\u5408\u7d22\u5f15
CREATE INDEX idx_borrow_rno_bno
ON borrow(rno,bno);
\u67e5\u770b\u7d22\u5f15
SHOW INDEX FROM book;
SHOW INDEX FROM reader;
SHOW INDEX FROM borrow;
\u5220\u9664\u7d22\u5f15
DROP INDEX idx_book_bname ON book;
DROP INDEX idx_reader_phone ON reader;
DROP INDEX idx_borrow_rno_bno ON borrow;<\/pre>\n\n\n\n13.\u6570\u636e\u5b8c\u6574\u6027\u7ea6\u675f\u9a8c\u8bc1\u4e0e\u7ea7\u8054\u64cd\u4f5c<\/h2>\n\n\n\n1.\u5b9e\u4f53\u5b8c\u6574\u6027\u9a8c\u8bc1\uff1a\u4e3b\u952e\u4e0d\u80fd\u4e3a\u7a7a
INSERT INTO book(bno,bname,author,press,pubyear,stock)
VALUES(NULL,'\u6d4b\u8bd5\u4e66','\u6d4b\u8bd5\u4f5c\u8005','\u6d4b\u8bd5\u51fa\u7248\u793e',2020,1);
\u8bf4\u660e\uff1a
bno \u662f book \u8868\u4e3b\u952e\uff0c\u4e3b\u952e\u4e0d\u80fd\u4e3a\u7a7a\uff0c\u56e0\u6b64\u63d2\u5165\u5931\u8d25\u3002
2.\u53c2\u7167\u5b8c\u6574\u6027\u9a8c\u8bc1\uff1a\u63d2\u5165\u4e0d\u5b58\u5728\u7684\u56fe\u4e66\u7f16\u53f7
INSERT INTO borrow(rno,bno,borrowdate,returndate,actualdate)
VALUES('R2024001','B999','2025-05-01','2025-05-15',NULL);
\u8bf4\u660e\uff1a
B999 \u5728 book \u8868\u4e2d\u4e0d\u5b58\u5728\uff0cborrow.bno \u662f\u5916\u952e\uff0c\u56e0\u6b64\u8fdd\u53cd\u53c2\u7167\u5b8c\u6574\u6027\u3002
3.\u7528\u6237\u5b9a\u4e49\u5b8c\u6574\u6027\u9a8c\u8bc1\uff1a\u5e93\u5b58\u4e0d\u80fd\u5c0f\u4e8e0
UPDATE book
SET stock = -1
WHERE bno = 'B001';
\u8bf4\u660e\uff1a
stock \u5b57\u6bb5\u8bbe\u7f6e\u4e86 CHECK(stock>=0)\uff0c\u5e93\u5b58\u4e0d\u80fd\u4e3a\u8d1f\u6570\u3002
4.\u7528\u6237\u5b9a\u4e49\u5b8c\u6574\u6027\u9a8c\u8bc1\uff1a\u5e93\u5b58\u4e0d\u80fd\u5c0f\u4e8e0
UPDATE book
SET stock = -1
WHERE bno = 'B001';
\u8bf4\u660e\uff1a
stock \u5b57\u6bb5\u8bbe\u7f6e\u4e86 CHECK(stock>=0)\uff0c\u5e93\u5b58\u4e0d\u80fd\u4e3a\u8d1f\u6570\u3002
5.ON UPDATE CASCADE \u6d4b\u8bd5
UPDATE reader
SET rno = 'R2024999'
WHERE rno = 'R2024003';
SELECT * FROM borrow
WHERE rno = 'R2024999';
\u8bf4\u660e\uff1a
reader.rno \u66f4\u65b0\u540e\uff0cborrow \u8868\u4e2d\u5bf9\u5e94\u7684\u5916\u952e rno \u4f1a\u81ea\u52a8\u540c\u6b65\u66f4\u65b0\u3002<\/pre>\n\n\n\n14.\u89e6\u53d1\u5668<\/h2>\n\n\n\n\u51c6\u5907\uff1a\u5220\u9664\u65e7\u89e6\u53d1\u5668
DROP TRIGGER IF EXISTS trg_borrow_before_insert;
DROP TRIGGER IF EXISTS trg_return_after_update;
DROP TRIGGER IF EXISTS trg_reader_before_delete;
\u521b\u5efa\u5220\u9664\u8bfb\u8005\u65e5\u5fd7\u8868
CREATE TABLE reader_delete_log(
logid INT AUTO_INCREMENT PRIMARY KEY,
rno CHAR(12),
rname VARCHAR(20),
dept VARCHAR(40),
delete_time DATETIME DEFAULT CURRENT_TIMESTAMP
);
1.\u501f\u4e66\u65f6\u81ea\u52a8\u51cf\u5c11\u5e93\u5b58
DELIMITER \/\/
CREATE TRIGGER trg_borrow_before_insert
BEFORE INSERT ON borrow
FOR EACH ROW
BEGIN
DECLARE v_stock INT;
SELECT stock INTO v_stock
FROM book
WHERE bno = NEW.bno;
IF v_stock <= 0 THEN
SIGNAL SQLSTATE '45000'
SET MESSAGE_TEXT = '\u5e93\u5b58\u4e0d\u8db3\uff0c\u4e0d\u80fd\u501f\u4e66';
ELSE
UPDATE book
SET stock = stock - 1
WHERE bno = NEW.bno;
END IF;
END \/\/
DELIMITER ;
\u6d4b\u8bd5\uff1a
SELECT stock FROM book WHERE bno='B003';
INSERT INTO borrow(rno,bno,borrowdate,returndate,actualdate)
VALUES('R2024002','B003','2025-05-01','2025-05-15',NULL);
SELECT stock FROM book WHERE bno='B003';
2.\u8fd8\u4e66\u65f6\u81ea\u52a8\u589e\u52a0\u5e93\u5b58\u5e76\u8ba1\u7b97\u7f5a\u6b3e
DELIMITER \/\/
CREATE TRIGGER trg_return_after_update
AFTER UPDATE ON borrow
FOR EACH ROW
BEGIN
IF OLD.actualdate IS NULL AND NEW.actualdate IS NOT NULL THEN
UPDATE book
SET stock = stock + 1
WHERE bno = NEW.bno;
UPDATE borrow
SET fine =
CASE
WHEN NEW.actualdate > NEW.returndate
THEN DATEDIFF(NEW.actualdate, NEW.returndate) * 1
ELSE 0
END
WHERE borrowid = NEW.borrowid;
END IF;
END \/\/
DELIMITER ;
\u6d4b\u8bd5\uff1a
UPDATE borrow
SET actualdate = '2025-05-18'
WHERE rno='R2024002'
AND bno='B003'
AND borrowdate='2025-05-01';
SELECT * FROM borrow
WHERE rno='R2024002'
AND bno='B003';
SELECT stock FROM book WHERE bno='B003';
3.\u5220\u9664\u8bfb\u8005\u524d\u8bb0\u5f55\u65e5\u5fd7
DELIMITER \/\/
CREATE TRIGGER trg_reader_before_delete
BEFORE DELETE ON reader
FOR EACH ROW
BEGIN
INSERT INTO reader_delete_log(rno,rname,dept)
VALUES(OLD.rno, OLD.rname, OLD.dept);
END \/\/
DELIMITER ;
\u6d4b\u8bd5\uff1a
INSERT INTO reader
VALUES('R2024888','\u65e5\u5fd7\u6d4b\u8bd5','\u7537','\u6d4b\u8bd5\u5b66\u9662','\u65e0');
DELETE FROM reader
WHERE rno='R2024888';
SELECT * FROM reader_delete_log;<\/pre>\n\n\n\n15.\u6570\u636e\u5b89\u5168\u6027<\/h2>\n\n\n\n1.\u521b\u5efa\u7528\u6237\u5e76\u6388\u4e88\u67e5\u8be2\u6743\u9650
CREATE USER 'lib_user1'@'localhost'
IDENTIFIED BY '123456';
GRANT SELECT
ON library_db.book
TO 'lib_user1'@'localhost';
\u67e5\u770b\u6743\u9650\uff1a
SHOW GRANTS FOR 'lib_user1'@'localhost';
2.\u6388\u4e88\u6743\u9650\u5e76\u5141\u8bb8\u8f6c\u6388\u6743
GRANT SELECT, INSERT
ON library_db.reader
TO 'lib_user1'@'localhost'
WITH GRANT OPTION;
\u8bf4\u660e\uff1a
WITH GRANT OPTION \u8868\u793a\u8be5\u7528\u6237\u53ef\u4ee5\u5c06\u81ea\u5df1\u62e5\u6709\u7684\u6743\u9650\u518d\u6388\u4e88\u5176\u4ed6\u7528\u6237\u3002
3.\u56de\u6536\u6743\u9650
REVOKE INSERT
ON library_db.reader
FROM 'lib_user1'@'localhost';
4.\u521b\u5efa\u89d2\u8272\u5e76\u6388\u6743
CREATE ROLE 'reader_role';
GRANT SELECT
ON library_db.*
TO 'reader_role';
CREATE USER 'lib_user2'@'localhost'
IDENTIFIED BY '123456';
GRANT 'reader_role'
TO 'lib_user2'@'localhost';
SET DEFAULT ROLE 'reader_role'
TO 'lib_user2'@'localhost';<\/pre>\n\n\n\n16.\u89c6\u56fe\u4e0e\u6d3e\u751f\u8868<\/h2>\n\n\n\n1.\u5e26\u805a\u5408\u51fd\u6570\u7684\u89c6\u56fe\uff1a\u7edf\u8ba1\u6bcf\u4e2a\u8bfb\u8005\u501f\u9605\u6b21\u6570
CREATE VIEW v_reader_borrow_count AS
SELECT r.rno, r.rname, COUNT(br.borrowid) AS borrow_count
FROM reader r
LEFT JOIN borrow br
ON r.rno = br.rno
GROUP BY r.rno, r.rname;
\u67e5\u8be2\uff1a
SELECT * FROM v_reader_borrow_count;
2.\u6d3e\u751f\u8868\uff1a\u67e5\u8be2\u501f\u9605\u6b21\u6570\u5927\u4e8e1\u7684\u8bfb\u8005
SELECT *
FROM (
SELECT rno, COUNT(*) AS borrow_count
FROM borrow
GROUP BY rno
) AS t
WHERE t.borrow_count > 1;
3.WITH \u5b50\u53e5\u7edf\u8ba1\u6bcf\u4f4d\u8bfb\u8005\u501f\u9605\u6570\u91cf
WITH reader_count AS (
SELECT rno, COUNT(*) AS total
FROM borrow
GROUP BY rno
)
SELECT r.rno, r.rname, rc.total
FROM reader r
LEFT JOIN reader_count rc
ON r.rno = rc.rno;
4.WITH \u5b50\u53e5\uff1a\u67e5\u8be2\u672a\u5f52\u8fd8\u56fe\u4e66
WITH unreturned AS (
SELECT br.borrowid, r.rname, b.bname,
br.borrowdate, br.returndate
FROM borrow br
JOIN reader r ON br.rno = r.rno
JOIN book b ON br.bno = b.bno
WHERE br.actualdate IS NULL
)
SELECT * FROM unreturned;<\/pre>\n\n\n\n17.\u6269\u5c55\u601d\u8003<\/h2>\n\n\n\n\n- \u5982\u4f55\u5904\u7406\u5206\u7c7b\u5b9e\u4f53\u7684\u81ea\u5173\u8054\uff1f<\/li>\n<\/ol>\n\n\n\n
\u5206\u7c7b\u5b9e\u4f53\u5b58\u5728\u201c\u4e0a\u7ea7\u5206\u7c7b\u201d\u548c\u201c\u4e0b\u7ea7\u5206\u7c7b\u201d\u7684\u5173\u7cfb\uff0c\u56e0\u6b64\u53ef\u4ee5\u5728 category \u8868\u4e2d\u8bbe\u7f6e parentid \u5b57\u6bb5\u3002
category(
cid,
cname,
parentid
)
\u5176\u4e2d cid \u662f\u5206\u7c7b\u7f16\u53f7\uff0cparentid \u662f\u4e0a\u7ea7\u5206\u7c7b\u7f16\u53f7\uff0c\u540c\u65f6 parentid \u4e5f\u662f\u6307\u5411 category.cid \u7684\u5916\u952e\u3002
\u5982\u679c\u67d0\u5206\u7c7b\u6ca1\u6709\u4e0a\u7ea7\u5206\u7c7b\uff0c\u5219 parentid \u53ef\u4ee5\u4e3a\u7a7a\u3002
\u8fd9\u79cd\u8bbe\u8ba1\u53ef\u4ee5\u8868\u793a\u6811\u5f62\u7ed3\u6784\uff0c\u4f8b\u5982\uff1a
\u56fe\u4e66
\u251c\u2500\u2500 \u8ba1\u7b97\u673a
\u2502 \u251c\u2500\u2500 \u6570\u636e\u5e93
\u2502 \u2514\u2500\u2500 \u7f51\u7edc\u6280\u672f
\u2514\u2500\u2500 \u6587\u5b66
\u2514\u2500\u2500 \u79d1\u5e7b\u5c0f\u8bf4<\/pre>\n\n\n\n
\n\n\n\n2. \u501f\u9605\u5173\u7cfb\u662f\u5426\u53ef\u80fd\u5b58\u5728\u6570\u636e\u5197\u4f59\uff1f<\/h2>\n\n\n\n\u501f\u9605\u8868\u5982\u679c\u53ea\u4fdd\u5b58 rno\u3001bno\u3001borrowdate\u3001returndate\u3001actualdate \u7b49\u4fe1\u606f\uff0c\u5219\u5197\u4f59\u8f83\u5c11\u3002
\u4f46\u662f\u5982\u679c\u5728 borrow \u8868\u4e2d\u540c\u65f6\u4fdd\u5b58\u8bfb\u8005\u59d3\u540d rname\u3001\u56fe\u4e66\u540d\u79f0 bname\u3001\u51fa\u7248\u793e press \u7b49\u4fe1\u606f\uff0c\u5c31\u4f1a\u4ea7\u751f\u6570\u636e\u5197\u4f59\u3002
\u4f8b\u5982\uff1a
borrow(borrowid, rno, rname, bno, bname, borrowdate)
\u5176\u4e2d rname \u4f9d\u8d56 rno\uff0cbname \u4f9d\u8d56 bno\uff0c\u800c\u4e0d\u662f\u76f4\u63a5\u4f9d\u8d56 borrowid\uff0c\u4f1a\u4ea7\u751f\u4f20\u9012\u4f9d\u8d56\u3002
\u89c4\u8303\u5316\u65b9\u6848\uff1a
\u5c06\u8bfb\u8005\u4fe1\u606f\u4fdd\u5b58\u5728 reader \u8868\uff1b
\u5c06\u56fe\u4e66\u4fe1\u606f\u4fdd\u5b58\u5728 book \u8868\uff1b
borrow \u8868\u53ea\u4fdd\u5b58\u8bfb\u8005\u8bc1\u53f7\u548c\u56fe\u4e66\u7f16\u53f7\u4f5c\u4e3a\u5916\u952e\u3002<\/pre>\n\n\n\n
\n\n\n\n3. \u5982\u4f55\u9632\u6b62\u5e93\u5b58\u4e3a\u8d1f\u6570\uff1f<\/h2>\n\n\n\n\u53ef\u4ee5\u4ece\u4e24\u4e2a\u65b9\u9762\u9632\u6b62\u5e93\u5b58\u4e3a\u8d1f\u6570\uff1a
\u7b2c\u4e00\uff0c\u5728 book \u8868\u4e2d\u8bbe\u7f6e CHECK(stock >= 0) \u7ea6\u675f\uff0c\u4fdd\u8bc1\u5e93\u5b58\u4e0d\u80fd\u5c0f\u4e8e0\u3002
\u7b2c\u4e8c\uff0c\u5728\u501f\u4e66\u89e6\u53d1\u5668\u4e2d\u5224\u65ad\u5e93\u5b58\u6570\u91cf\u3002
\u5f53\u63d2\u5165 borrow \u501f\u9605\u8bb0\u5f55\u65f6\uff0c\u5148\u67e5\u8be2\u56fe\u4e66\u5e93\u5b58\u3002
\u5982\u679c\u5e93\u5b58\u5c0f\u4e8e\u7b49\u4e8e0\uff0c\u5219\u4f7f\u7528 SIGNAL \u629b\u51fa\u9519\u8bef\uff0c\u963b\u6b62\u501f\u4e66\u64cd\u4f5c\uff1b
\u5982\u679c\u5e93\u5b58\u5927\u4e8e0\uff0c\u5219\u5141\u8bb8\u501f\u9605\uff0c\u5e76\u81ea\u52a8\u5c06\u5e93\u5b58\u51cf1\u3002
\u8fd9\u6837\u53ef\u4ee5\u4fdd\u8bc1\u501f\u4e66\u65f6\u4e0d\u4f1a\u51fa\u73b0\u5e93\u5b58\u4e3a\u8d1f\u6570\u7684\u60c5\u51b5\u3002<\/pre>\n\n\n\n
\n\n\n\n4. \u9884\u7ea6\u56fe\u4e66\u529f\u80fd\u9700\u8981\u589e\u52a0\u54ea\u4e9b\u5b9e\u4f53\u548c\u5173\u7cfb\uff1f<\/h2>\n\n\n\n\u5982\u679c\u7cfb\u7edf\u652f\u6301\u9884\u7ea6\u56fe\u4e66\u529f\u80fd\uff0c\u53ef\u4ee5\u589e\u52a0 reservation \u9884\u7ea6\u8868\u3002
reservation(
reserveid,
rno,
bno,
reservedate,
status
)
\u5176\u4e2d\uff1a
reserveid \u8868\u793a\u9884\u7ea6\u7f16\u53f7\uff1b
rno \u662f\u8bfb\u8005\u8bc1\u53f7\uff0c\u5916\u952e\u5f15\u7528 reader.rno\uff1b
bno \u662f\u56fe\u4e66\u7f16\u53f7\uff0c\u5916\u952e\u5f15\u7528 book.bno\uff1b
reservedate \u8868\u793a\u9884\u7ea6\u65e5\u671f\uff1b
status \u8868\u793a\u9884\u7ea6\u72b6\u6001\uff0c\u5982\u201c\u9884\u7ea6\u4e2d\u201d\u201c\u5df2\u53d6\u6d88\u201d\u201c\u5df2\u5b8c\u6210\u201d\u3002
\u65b0\u589e\u5173\u7cfb\uff1a
\u4e00\u4e2a\u8bfb\u8005\u53ef\u4ee5\u9884\u7ea6\u591a\u672c\u56fe\u4e66\uff1b
\u4e00\u672c\u56fe\u4e66\u53ef\u4ee5\u88ab\u591a\u4e2a\u8bfb\u8005\u9884\u7ea6\uff1b
\u8bfb\u8005\u548c\u56fe\u4e66\u4e4b\u95f4\u901a\u8fc7 reservation \u8868\u5f62\u6210 m:n \u8054\u7cfb\u3002<\/pre>\n\n\n\n
\n\n\n\n5. \u4e3a\u4ec0\u4e48\u9075\u5faa\u6700\u5c0f\u6743\u9650\u539f\u5219\uff1f<\/h2>\n\n\n\n\u6700\u5c0f\u6743\u9650\u539f\u5219\u662f\u6307\u53ea\u7ed9\u7528\u6237\u5b8c\u6210\u5de5\u4f5c\u6240\u5fc5\u9700\u7684\u6743\u9650\uff0c\u4e0d\u6388\u4e88\u591a\u4f59\u6743\u9650\u3002
\u5728\u672c\u5b9e\u9a8c\u4e2d\uff0c\u5982\u679c\u67d0\u7528\u6237\u53ea\u8d1f\u8d23\u67e5\u8be2\u56fe\u4e66\u4fe1\u606f\uff0c\u5219\u53ea\u6388\u4e88 SELECT \u6743\u9650\u5373\u53ef\uff0c\u4e0d\u5e94\u8be5\u6388\u4e88 INSERT\u3001UPDATE\u3001DELETE \u7b49\u6743\u9650\u3002
\u4f8b\u5982\uff1a
GRANT SELECT ON library_db.book TO 'lib_user1'@'localhost';
\u8fd9\u6837\u53ef\u4ee5\u9632\u6b62\u7528\u6237\u8bef\u5220\u3001\u8bef\u6539\u6570\u636e\uff0c\u63d0\u9ad8\u6570\u636e\u5e93\u5b89\u5168\u6027\u3002
\u5982\u679c\u540e\u7eed\u4e0d\u518d\u9700\u8981\u67d0\u9879\u6743\u9650\uff0c\u8fd8\u53ef\u4ee5\u4f7f\u7528 REVOKE \u56de\u6536\u6743\u9650\u3002<\/pre>\n\n\n\n
\n\n\n\n6. \u5e76\u53d1\u501f\u9605\u5e93\u5b58\u4ec5\u52691\u672c\u7684\u56fe\u4e66\u4f1a\u4ea7\u751f\u4ec0\u4e48\u95ee\u9898\uff1f\u5982\u4f55\u89e3\u51b3\uff1f<\/h2>\n\n\n\n\u5f53\u591a\u7528\u6237\u540c\u65f6\u501f\u9605\u540c\u4e00\u672c\u5e93\u5b58\u4ec5\u52691\u672c\u7684\u56fe\u4e66\u65f6\uff0c\u53ef\u80fd\u51fa\u73b0\u8d85\u5356\u95ee\u9898\u3002
\u4f8b\u5982\u4e24\u4e2a\u7528\u6237\u540c\u65f6\u8bfb\u53d6\u5e93\u5b58 stock=1\uff0c\u90fd\u8ba4\u4e3a\u53ef\u4ee5\u501f\u9605\uff0c\u7136\u540e\u540c\u65f6\u63d2\u5165\u501f\u9605\u8bb0\u5f55\u5e76\u6267\u884c\u5e93\u5b58\u51cf1\uff0c\u6700\u7ec8\u53ef\u80fd\u5bfc\u81f4\u5e93\u5b58\u5f02\u5e38\u6216\u51fa\u73b0\u8d85\u989d\u501f\u9605\u3002
\u89e3\u51b3\u65b9\u6cd5\uff1a
1. \u4f7f\u7528\u4e8b\u52a1\u4fdd\u8bc1\u501f\u4e66\u64cd\u4f5c\u7684\u539f\u5b50\u6027\uff1b
2. \u4f7f\u7528 SELECT ... FOR UPDATE \u5bf9\u56fe\u4e66\u5e93\u5b58\u8bb0\u5f55\u52a0\u884c\u7ea7\u9501\uff1b
3. \u5728\u89e6\u53d1\u5668\u4e2d\u5224\u65ad\u5e93\u5b58\u662f\u5426\u5927\u4e8e0\uff1b
4. \u7ed9 stock \u5b57\u6bb5\u8bbe\u7f6e CHECK(stock >= 0) \u7ea6\u675f\u3002
\u793a\u4f8b\uff1a
START TRANSACTION;
SELECT stock
FROM book
WHERE bno='B001'
FOR UPDATE;
UPDATE book
SET stock = stock - 1
WHERE bno='B001'
AND stock > 0;
INSERT INTO borrow(rno,bno,borrowdate,returndate)
VALUES('R2024001','B001','2025-05-01','2025-05-15');
COMMIT;
\u8fd9\u6837\u53ef\u4ee5\u907f\u514d\u591a\u4e2a\u7528\u6237\u540c\u65f6\u4fee\u6539\u5e93\u5b58\u5bfc\u81f4\u6570\u636e\u4e0d\u4e00\u81f4\u3002<\/pre>\n\n\n\n
\n\n\n\n\u5b9e\u9a8c\u603b\u7ed3<\/h1>\n\n\n\n \u901a\u8fc7\u672c\u6b21\u56fe\u4e66\u501f\u9605\u7ba1\u7406\u7cfb\u7edf\u7efc\u5408\u5b9e\u9a8c\uff0c\u6211\u7cfb\u7edf\u5730\u5b8c\u6210\u4e86\u6570\u636e\u5e93\u8bbe\u8ba1\u4e0e\u5b9e\u73b0\u7684\u5168\u8fc7\u7a0b\u3002\u5b9e\u9a8c\u4ece\u9700\u6c42\u5206\u6790\u5f00\u59cb\uff0c\u9010\u6b65\u5b8c\u6210 E-R \u56fe\u8bbe\u8ba1\u3001\u5173\u7cfb\u6a21\u5f0f\u8f6c\u6362\u3001\u7269\u7406\u8868\u7ed3\u6784\u8bbe\u8ba1\u3001\u6570\u636e\u63d2\u5165\u3001\u67e5\u8be2\u64cd\u4f5c\u3001\u89c6\u56fe\u3001\u7d22\u5f15\u3001\u5b8c\u6574\u6027\u7ea6\u675f\u3001\u89e6\u53d1\u5668\u548c\u6743\u9650\u7ba1\u7406\u7b49\u5185\u5bb9\uff0c\u4f7f\u6211\u5bf9\u6570\u636e\u5e93\u5e94\u7528\u7cfb\u7edf\u7684\u8bbe\u8ba1\u6d41\u7a0b\u6709\u4e86\u66f4\u52a0\u5b8c\u6574\u7684\u8ba4\u8bc6\u3002
\u200b
\u5728\u5b9e\u9a8c\u8fc7\u7a0b\u4e2d\uff0c\u6211\u9996\u5148\u6839\u636e\u56fe\u4e66\u9986\u4e1a\u52a1\u9700\u6c42\u5206\u6790\u51fa\u56fe\u4e66\u3001\u8bfb\u8005\u3001\u501f\u9605\u3001\u51fa\u7248\u793e\u3001\u5206\u7c7b\u7b49\u5b9e\u4f53\uff0c\u5e76\u660e\u786e\u4e86\u5b83\u4eec\u4e4b\u95f4\u7684\u8054\u7cfb\u7c7b\u578b\u3002\u4f8b\u5982\uff0c\u51fa\u7248\u793e\u4e0e\u56fe\u4e66\u4e4b\u95f4\u662f\u4e00\u5bf9\u591a\u5173\u7cfb\uff0c\u5206\u7c7b\u4e0e\u56fe\u4e66\u4e4b\u95f4\u662f\u4e00\u5bf9\u591a\u5173\u7cfb\uff0c\u8bfb\u8005\u4e0e\u56fe\u4e66\u4e4b\u95f4\u901a\u8fc7\u501f\u9605\u8868\u5f62\u6210\u591a\u5bf9\u591a\u5173\u7cfb\u3002\u901a\u8fc7 E-R \u56fe\u8bbe\u8ba1\uff0c\u6211\u8fdb\u4e00\u6b65\u7406\u89e3\u4e86\u6982\u5ff5\u7ed3\u6784\u8bbe\u8ba1\u5728\u6570\u636e\u5e93\u5f00\u53d1\u4e2d\u7684\u91cd\u8981\u4f5c\u7528\u3002
\u200b
\u5728\u903b\u8f91\u7ed3\u6784\u8bbe\u8ba1\u9636\u6bb5\uff0c\u6211\u5c06 E-R \u56fe\u8f6c\u6362\u4e3a\u5173\u7cfb\u6a21\u5f0f\uff0c\u5e76\u5206\u6790\u5404\u8868\u662f\u5426\u6ee1\u8db3\u7b2c\u4e09\u8303\u5f0f\u3002\u901a\u8fc7\u89c4\u8303\u5316\u8bbe\u8ba1\uff0c\u907f\u514d\u4e86\u5728\u501f\u9605\u8868\u4e2d\u91cd\u590d\u4fdd\u5b58\u8bfb\u8005\u59d3\u540d\u3001\u56fe\u4e66\u540d\u79f0\u7b49\u4fe1\u606f\uff0c\u51cf\u5c11\u4e86\u6570\u636e\u5197\u4f59\uff0c\u63d0\u9ad8\u4e86\u6570\u636e\u4e00\u81f4\u6027\u3002\u5728\u7269\u7406\u8bbe\u8ba1\u9636\u6bb5\uff0c\u6211\u4f7f\u7528 SQL \u521b\u5efa\u6570\u636e\u5e93\u548c\u6570\u636e\u8868\uff0c\u8bbe\u7f6e\u4e86\u4e3b\u952e\u3001\u5916\u952e\u3001\u975e\u7a7a\u3001\u9ed8\u8ba4\u503c\u548c CHECK \u7ea6\u675f\uff0c\u5bf9\u5b9e\u4f53\u5b8c\u6574\u6027\u3001\u53c2\u7167\u5b8c\u6574\u6027\u548c\u7528\u6237\u5b9a\u4e49\u5b8c\u6574\u6027\u6709\u4e86\u66f4\u6df1\u523b\u7684\u7406\u89e3\u3002
\u200b
\u5728\u6570\u636e\u64cd\u4f5c\u90e8\u5206\uff0c\u6211\u7ec3\u4e60\u4e86 INSERT\u3001UPDATE\u3001DELETE \u548c SELECT \u8bed\u53e5\uff0c\u5e76\u5b8c\u6210\u4e86\u57fa\u7840\u67e5\u8be2\u3001\u805a\u5408\u67e5\u8be2\u3001\u591a\u8868\u8fde\u63a5\u67e5\u8be2\u3001\u5d4c\u5957\u67e5\u8be2\u548c\u96c6\u5408\u67e5\u8be2\u7b49\u5185\u5bb9\u3002\u901a\u8fc7\u8fd9\u4e9b\u7ec3\u4e60\uff0c\u6211\u638c\u63e1\u4e86 SQL \u67e5\u8be2\u8bed\u53e5\u7684\u5e38\u89c1\u5199\u6cd5\uff0c\u5c24\u5176\u662f\u591a\u8868\u8fde\u63a5\u548c\u5d4c\u5957\u67e5\u8be2\u7684\u4f7f\u7528\u65b9\u6cd5\u3002\u5b9e\u9a8c\u4e2d\u8fd8\u521b\u5efa\u4e86\u89c6\u56fe\u548c\u7d22\u5f15\uff0c\u7406\u89e3\u4e86\u89c6\u56fe\u53ef\u4ee5\u7b80\u5316\u590d\u6742\u67e5\u8be2\uff0c\u7d22\u5f15\u53ef\u4ee5\u63d0\u9ad8\u67e5\u8be2\u6548\u7387\uff0c\u4f46\u4e5f\u4f1a\u589e\u52a0\u7ef4\u62a4\u6210\u672c\u3002
\u200b
\u5728\u89e6\u53d1\u5668\u90e8\u5206\uff0c\u6211\u5b9e\u73b0\u4e86\u501f\u4e66\u81ea\u52a8\u51cf\u5c11\u5e93\u5b58\u3001\u8fd8\u4e66\u81ea\u52a8\u589e\u52a0\u5e93\u5b58\u5e76\u8ba1\u7b97\u7f5a\u6b3e\u3001\u5220\u9664\u8bfb\u8005\u524d\u8bb0\u5f55\u65e5\u5fd7\u7b49\u529f\u80fd\u3002\u901a\u8fc7\u89e6\u53d1\u5668\u5b9e\u9a8c\uff0c\u6211\u8ba4\u8bc6\u5230\u6570\u636e\u5e93\u4e0d\u4ec5\u53ef\u4ee5\u5b58\u50a8\u6570\u636e\uff0c\u8fd8\u53ef\u4ee5\u5728\u7279\u5b9a\u64cd\u4f5c\u53d1\u751f\u65f6\u81ea\u52a8\u6267\u884c\u4e00\u4e9b\u4e1a\u52a1\u903b\u8f91\u3002\u5b9e\u9a8c\u8fc7\u7a0b\u4e2d\u4e5f\u9047\u5230\u4e86\u4e00\u4e9b\u95ee\u9898\uff0c\u4f8b\u5982\u5916\u952e\u7ea6\u675f\u5bfc\u81f4\u6570\u636e\u65e0\u6cd5\u5220\u9664\u3001CHECK \u7ea6\u675f\u63d2\u5165\u5931\u8d25\u3001\u89e6\u53d1\u5668\u8bed\u6cd5\u9519\u8bef\u7b49\u3002\u901a\u8fc7\u67e5\u770b\u9519\u8bef\u4fe1\u606f\u3001\u4fee\u6539 SQL \u8bed\u53e5\u548c\u53cd\u590d\u6d4b\u8bd5\uff0c\u6700\u7ec8\u89e3\u51b3\u4e86\u8fd9\u4e9b\u95ee\u9898\u3002
\u200b
\u901a\u8fc7\u672c\u6b21\u5b9e\u9a8c\uff0c\u6211\u4e0d\u4ec5\u5de9\u56fa\u4e86\u6570\u636e\u5e93\u7406\u8bba\u77e5\u8bc6\uff0c\u4e5f\u63d0\u9ad8\u4e86 SQL \u7f16\u5199\u80fd\u529b\u548c\u6570\u636e\u5e93\u8c03\u8bd5\u80fd\u529b\u3002\u4eca\u540e\u5728\u8bbe\u8ba1\u6570\u636e\u5e93\u7cfb\u7edf<\/pre>\n","protected":false},"excerpt":{"rendered":"\u6570\u636e\u5e93\u7efc\u5408\u5b9e\u9a8c 1.\u9700\u6c42\u5206\u6790 \u67d0\u5927\u578b\u56fe\u4e66\u9986\u9700\u8981\u5f00\u53d1\u4e00\u5957\u6570\u5b57\u5316\u501f\u9605\u7ba1\u7406\u7cfb\u7edf\uff0c\u4e3b\u8981\u4e1a\u52a1\u9700\u6c42\u5982\u4e0b\uff1a \u56fe\u4e66\u4fe1\u606f\uff1a\u8bb0\u5f55\u56fe […]<\/p>\n","protected":false},"author":1,"featured_media":448,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[9],"tags":[],"class_list":["post-446","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-wenzhang"],"_links":{"self":[{"href":"https:\/\/fg2025.cn\/index.php\/wp-json\/wp\/v2\/posts\/446","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/fg2025.cn\/index.php\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/fg2025.cn\/index.php\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/fg2025.cn\/index.php\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/fg2025.cn\/index.php\/wp-json\/wp\/v2\/comments?post=446"}],"version-history":[{"count":0,"href":"https:\/\/fg2025.cn\/index.php\/wp-json\/wp\/v2\/posts\/446\/revisions"}],"wp:attachment":[{"href":"https:\/\/fg2025.cn\/index.php\/wp-json\/wp\/v2\/media?parent=446"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/fg2025.cn\/index.php\/wp-json\/wp\/v2\/categories?post=446"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/fg2025.cn\/index.php\/wp-json\/wp\/v2\/tags?post=446"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}
ADD pages INT;
\u200b
ALTER TABLE reader
ADD email VARCHAR(50) UNIQUE;
\u200b
\u9a8c\u8bc1\uff1a
desc book
desc reader
\u200b
ALTER TABLE book
MODIFY author VARCHAR(50);
\u200b
ALTER TABLE reader
MODIFY phone VARCHAR(20)
DEFAULT '\u65e0';
\u200b
SHOW CREATE TABLE borrow;
ALTER TABLE book
DROP COLUMN pages;
\u200b
ALTER TABLE borrow
DROP FOREIGN KEY fk_reader;<\/pre>\n\n\n\n
4.\u6570\u636e\u63d2\u5165<\/h2>\n\n\n\n INSERT INTO book VALUES
('B001','\u6570\u636e\u5e93\u7cfb\u7edf\u6982\u8bba','\u738b\u73ca',
'\u9ad8\u7b49\u6559\u80b2\u51fa\u7248\u793e',2018,5),
\u200b
('B002','C\u7a0b\u5e8f\u8bbe\u8ba1\u8bed\u8a00','K&R',
'\u673a\u68b0\u5de5\u4e1a\u51fa\u7248\u793e',2015,3),
\u200b
('B003','\u4e09\u4f53','\u5218\u6148\u6b23',
'\u91cd\u5e86\u51fa\u7248\u793e',2010,8),
\u200b
('B004','\u8ba1\u7b97\u673a\u7f51\u7edc','\u8c22\u5e0c\u4ec1',
'\u7535\u5b50\u5de5\u4e1a\u51fa\u7248\u793e',2018,4);
\u200b
INSERT INTO reader
VALUES
('R2024001','\u5f20\u660e','\u7537',
'\u8ba1\u7b97\u673a\u5b66\u9662','13812345678',
'zhangming@qq.com'),
\u200b
('R2024002','\u674e\u82b3','\u5973',
'\u4fe1\u606f\u5b66\u9662','13912345678',
'lifang@qq.com'),
\u200b
('R2024003','\u738b\u78ca','\u7537',
'\u6587\u5b66\u9662','13612345678',
'wanglei@qq.com');
\u200b
INSERT INTO borrow VALUES
(1,'R2024001','B001',
'2025-03-01',
'2025-03-15',
'2025-03-14'),
(2,'R2024001','B003',
'2025-03-10',
'2025-03-24',
NULL),
(3,'R2024002','B002',
'2025-04-01',
'2025-04-15',
NULL),
(4,'R2024003','B004',
'2025-03-20',
'2025-04-03',
'2025-04-05');<\/pre>\n\n\n\n4.1 \u8bbe\u8ba1\u8fdd\u53cd\u5916\u952e\u7ea6\u675f\u548ccheck\u7ea6\u675f\u5e76\u89e3\u91ca<\/h3>\n\n\n\n INSERT INTO borrow(
rno,bno,
borrowdate,
returndate)
VALUES(
'R999999',
'B001',
'2025-05-01',
'2025-05-15');
\u200b
\u9519\u8bef\uff1aCannot add or update a child row:
a foreign key constraint fails
\u200b
\u539f\u56e0\uff1aR999999\u5728reader\u8868\u4e2d\u4e0d\u5b58\u5728\uff0c
\u8fdd\u53cd\u53c2\u7167\u5b8c\u6574\u6027\u7ea6\u675f\u3002
\u200b
\u8fdd\u53cdcheck
INSERT INTO reader
VALUES(
'R2024004',
'\u8d75\u654f',
'\u672a\u77e5',
'\u827a\u672f\u5b66\u9662',
'13712345678');
\u200b
\u9519\u8bef\uff1aCheck constraint violated
\u200b
\u539f\u56e0\uff1arsex\u5b57\u6bb5\u53ea\u80fd\u53d6
\u7537 \u6216 \u5973\uff0c
\u56e0\u6b64\u8fdd\u53cdCHECK\u7ea6\u675f\u3002<\/pre>\n\n\n\n5.\u6570\u636e\u67e5\u8be2\uff08DQL-\u57fa\u7840\u67e5\u8be2\uff09<\/h2>\n\n\n\n 1.select\u67e5\u8be2\u5168\u90e8\u56fe\u4e66\u4fe1\u606f
select * from book;
2.\u67e5\u8be2\u5e93\u5b58\u5927\u4e8e3\u7684\u56fe\u4e66
SELECT bno,bname,stock
FROM book
WHERE stock > 3;
3.\u67e5\u8be22018\u5e74\u51fa\u7248\u4e14\u5e93\u5b58\u4e0d\u5c11\u4e8e4\u672c\u7684\u56fe\u4e66
SELECT bno,bname,pubyear,stock
FROM book
WHERE pubyear = 2018 AND stock >= 4;
4.\u67e5\u8be22015\u5e74\u81f32018\u5e74\u51fa\u7248\u7684\u56fe\u4e66
SELECT bno,bname,pubyear
FROM book
WHERE pubyear BETWEEN 2015 AND 2018;
5.\u67e5\u8be2\u51fa\u7248\u793e\u4e3a\u201c\u91cd\u5e86\u51fa\u7248\u793e\u201d\u6216\u201c\u9ad8\u7b49\u6559\u80b2\u51fa\u7248\u793e\u201d\u7684\u56fe\u4e66
SELECT bno,bname,press
FROM book
WHERE press IN('\u91cd\u5e86\u51fa\u7248\u793e','\u9ad8\u7b49\u6559\u80b2\u51fa\u7248\u793e');
6.\u67e5\u8be2\u4e66\u540d\u4e2d\u5305\u542b\u201c\u8ba1\u7b97\u673a\u201d\u7684\u56fe\u4e66
SELECT bno,bname
FROM book
WHERE bname LIKE '%\u8ba1\u7b97\u673a%';
7.\u67e5\u8be2\u5c1a\u672a\u5f52\u8fd8\u7684\u501f\u9605\u8bb0\u5f55
SELECT *
FROM borrow
WHERE actualdate IS NULL;
8.\u6309\u5e93\u5b58\u6570\u91cf\u964d\u5e8f\u67e5\u8be2\u56fe\u4e66
SELECT bno,bname,stock
FROM book
ORDER BY stock DESC;
9.\u67e5\u8be2\u5e93\u5b58\u6700\u591a\u7684\u524d2\u672c\u56fe\u4e66
SELECT bno,bname,stock
FROM book
ORDER BY stock DESC
LIMIT 2;
10.\u67e5\u8be2\u6240\u6709\u4e0d\u540c\u7684\u51fa\u7248\u793e
SELECT DISTINCT press
FROM book;<\/pre>\n\n\n\n6.\u6570\u636e\u66f4\u65b0\uff08update\/delete\uff09<\/h2>\n\n\n\n 1.\u5c06BOO1\u7684\u5e93\u5b58\u4fee\u6539\u4e3a6
UPDATE book
SET stock = 6
WHERE bno = 'B001';
\u200b
SELECT * FROM book WHERE bno='B001';
2.\u4fee\u6539\u5f20\u660e\u7684\u9662\u7cfb\u548c\u7535\u8bdd
UPDATE reader
SET dept = '\u4eba\u5de5\u667a\u80fd\u5b66\u9662',
phone = '18888888888'
WHERE rno = 'R2024001';
\u200b
SELECT * FROM reader WHERE rno='R2024001';
3.\u5c062018\u5e74\u51fa\u7248\u56fe\u4e66\u5e93\u5b58\u7edf\u4e00\u589e\u52a01
UPDATE book
SET stock = stock + 1
WHERE pubyear = 2018;
\u200b
SELECT * FROM book WHERE pubyear=2018;
4.\u5220\u9664\u4e00\u4e2a\u6d4b\u8bd5\u8bfb\u8005
INSERT INTO reader
VALUES('R2024999','\u6d4b\u8bd5\u8bfb\u8005','\u7537','\u6d4b\u8bd5\u5b66\u9662','\u65e0');
\u200b
DELETE FROM reader
WHERE rno = 'R2024999';
5.\u4e8b\u52a1\u63a7\u5236\uff1a\u66f4\u65b0\u540e\u56de\u6eda
START TRANSACTION;
\u200b
UPDATE book
SET stock = stock - 1
WHERE bno = 'B003';
\u200b
SELECT * FROM book WHERE bno='B003';
\u200b
ROLLBACK;
\u200b
SELECT * FROM book WHERE bno='B003';<\/pre>\n\n\n\n7.\u805a\u5408\u67e5\u8be2\u4e0e\u5206\u7ec4\u7edf\u8ba1<\/h2>\n\n\n\n 1.\u7edf\u8ba1\u56fe\u4e66\u603b\u6570
select count(*) as \u56fe\u4e66\u603b\u6570 from book;
2.\u7edf\u8ba1\u56fe\u4e66\u5e93\u5b58\u603b\u91cf
select sum(stock) as \u5e93\u5b58\u603b\u91cf from book;
3.\u7edf\u8ba1\u5e73\u5747\u5e93\u5b58
select avg(stock) as \u5e73\u5747\u5e93\u5b58 from book;
4.\u67e5\u8be2\u6700\u5927\u5e93\u5b58\u548c\u6700\u5c0f\u5e93\u5b58
SELECT MAX(stock) AS \u6700\u5927\u5e93\u5b58,
MIN(stock) AS \u6700\u5c0f\u5e93\u5b58
FROM book;
5.\u6309\u51fa\u7248\u793e\u7edf\u8ba1\u56fe\u4e66\u6570\u91cf\uff0c\u5e76\u7b5b\u9009\u6570\u91cf\u5927\u4e8e\u7b49\u4e8e1\u7684\u51fa\u7248\u793e
SELECT press, COUNT(*) AS \u56fe\u4e66\u6570\u91cf
FROM book
GROUP BY press
HAVING COUNT(*) >= 1;<\/pre>\n\n\n\n8.\u591a\u8868\u8fde\u63a5\u67e5\u8be2<\/h2>\n\n\n\n1.\u7b49\u503c\u8fde\u63a5\uff1a\u67e5\u8be2\u8bfb\u8005\u59d3\u540d\u548c\u6240\u501f\u56fe\u4e66
SELECT reader.rname, book.bname
FROM reader, borrow, book
WHERE reader.rno = borrow.rno
AND borrow.bno = book.bno;
2.\u5185\u8fde\u63a5\uff1a\u67e5\u8be2\u501f\u9605\u8bb0\u5f55\u8be6\u60c5
SELECT r.rname, b.bname, br.borrowdate, br.returndate
FROM borrow br
JOIN reader r ON br.rno = r.rno
JOIN book b ON br.bno = b.bno;
3.\u5de6\u5916\u8fde\u63a5\uff1a\u67e5\u8be2\u6240\u6709\u8bfb\u8005\u53ca\u5176\u501f\u9605\u8bb0\u5f55
SELECT r.rno, r.rname, br.borrowid, br.bno
FROM reader r
LEFT JOIN borrow br
ON r.rno = br.rno;
4.\u53f3\u5916\u8fde\u63a5\uff1a\u67e5\u8be2\u6240\u6709\u501f\u9605\u8bb0\u5f55\u53ca\u8bfb\u8005\u4fe1\u606f
SELECT r.rname, br.borrowid, br.bno
FROM reader r
RIGHT JOIN borrow br
ON r.rno = br.rno;
5.\u81ea\u8eab\u8fde\u63a5\uff1a\u67e5\u8be2\u540c\u4e00\u5e74\u51fa\u7248\u7684\u4e0d\u540c\u56fe\u4e66
SELECT a.bname AS \u56fe\u4e661,
b.bname AS \u56fe\u4e662,
a.pubyear AS \u51fa\u7248\u5e74\u4efd
FROM book a
JOIN book b
ON a.pubyear = b.pubyear
AND a.bno < b.bno;<\/pre>\n\n\n\n9.\u5d4c\u5957\u67e5\u8be2<\/h2>\n\n\n\n1.IN\uff1a\u67e5\u8be2\u501f\u8fc7\u4e66\u7684\u8bfb\u8005
SELECT *
FROM reader
WHERE rno IN(
SELECT rno FROM borrow
);
2.\u6bd4\u8f83\u8fd0\u7b97\u7b26\uff1a\u67e5\u8be2\u5e93\u5b58\u5927\u4e8e\u5e73\u5747\u5e93\u5b58\u7684\u56fe\u4e66
SELECT bno,bname,stock
FROM book
WHERE stock > (
SELECT AVG(stock)
FROM book
);
3.EXISTS\uff1a\u67e5\u8be2\u5b58\u5728\u501f\u9605\u8bb0\u5f55\u7684\u8bfb\u8005
SELECT *
FROM reader r
WHERE EXISTS(
SELECT *
FROM borrow br
WHERE br.rno = r.rno
);
4.ANY\uff1a\u67e5\u8be2\u5e93\u5b58\u5927\u4e8e\u4efb\u610f\u4e00\u672c2018\u5e74\u51fa\u7248\u56fe\u4e66\u5e93\u5b58\u7684\u56fe\u4e66
SELECT bno,bname,stock
FROM book
WHERE stock > ANY(
SELECT stock
FROM book
WHERE pubyear = 2018
);
5.ALL\uff1a\u67e5\u8be2\u5e93\u5b58\u4e0d\u5c11\u4e8e\u6240\u6709\u56fe\u4e66\u5e93\u5b58\u7684\u56fe\u4e66
SELECT bno,bname,stock
FROM book
WHERE stock >= ALL(
SELECT stock
FROM book
);<\/pre>\n\n\n\n10.\u96c6\u5408\u67e5\u8be2<\/h2>\n\n\n\n1.UNION\uff1a\u5408\u5e76\u8bfb\u8005\u59d3\u540d\u548c\u4f5c\u8005\u59d3\u540d\u5e76\u53bb\u91cd
SELECT rname AS name
FROM reader
UNION
SELECT author AS name
FROM book;
2.UNION ALL\uff1a\u5408\u5e76\u8bfb\u8005\u59d3\u540d\u548c\u4f5c\u8005\u59d3\u540d\uff0c\u4e0d\u53bb\u91cd
SELECT rname AS name
FROM reader
UNION ALL
SELECT author AS name
FROM book;
3.\u6a21\u62df INTERSECT\uff1a\u67e5\u8be2\u501f\u8fc7\u4e66\u7684\u8bfb\u8005\u8bc1\u53f7
SELECT rno
FROM reader
WHERE rno IN(
SELECT rno
FROM borrow
);
4.\u6a21\u62df EXCEPT\uff1a\u67e5\u8be2\u6ca1\u6709\u501f\u4e66\u7684\u8bfb\u8005
SELECT rno,rname
FROM reader
WHERE rno NOT IN(
SELECT rno
FROM borrow
);<\/pre>\n\n\n\n11.\u89c6\u56fe\u64cd\u4f5c<\/h2>\n\n\n\n1.\u521b\u5efa\u672a\u5f52\u8fd8\u56fe\u4e66\u89c6\u56fe
CREATE VIEW v_unreturned AS
SELECT br.borrowid, r.rname, b.bname,
br.borrowdate, br.returndate
FROM borrow br
JOIN reader r ON br.rno = r.rno
JOIN book b ON br.bno = b.bno
WHERE br.actualdate IS NULL;
2.\u67e5\u8be2\u89c6\u56fe
SELECT * FROM v_unreturned;
3.\u521b\u5efa\u5b66\u751f\u8bfb\u8005\u89c6\u56fe\uff0c\u5e26 WITH CHECK OPTION
CREATE VIEW v_student_reader AS
SELECT *
FROM reader
WHERE dept LIKE '%\u5b66\u9662%'
WITH CHECK OPTION;
4.\u6d4b\u8bd5\u53ef\u66f4\u65b0\u89c6\u56fe
UPDATE v_student_reader
SET phone = '18800000000'
WHERE rno = 'R2024002';
\u8bf4\u660e\uff1a
\u8be5\u89c6\u56fe\u57fa\u4e8e\u5355\u8868 reader \u521b\u5efa\uff0c\u6ca1\u6709\u805a\u5408\u51fd\u6570\u3001\u5206\u7ec4\u548c\u8fde\u63a5\uff0c\u56e0\u6b64\u5c5e\u4e8e\u53ef\u66f4\u65b0\u89c6\u56fe\u3002
5.\u521b\u5efa\u4e0d\u53ef\u66f4\u65b0\u7684\u805a\u5408\u89c6\u56fe
CREATE VIEW v_press_count AS
SELECT press, COUNT(*) AS total
FROM book
GROUP BY press;
\u8bf4\u660e\uff1a
\u8be5\u89c6\u56fe\u4f7f\u7528\u4e86 GROUP BY \u548c COUNT \u805a\u5408\u51fd\u6570\uff0c\u56e0\u6b64\u4e00\u822c\u4e0d\u80fd\u76f4\u63a5\u66f4\u65b0\u3002
6.\u5220\u9664\u89c6\u56fe
DROP VIEW v_unreturned;
DROP VIEW v_student_reader;
DROP VIEW v_press_count;<\/pre>\n\n\n\n12.\u7d22\u5f15<\/h2>\n\n\n\n1.\u521b\u5efa\u666e\u901a\u7d22\u5f15
CREATE INDEX idx_book_bname
ON book(bname);
2.\u521b\u5efa\u552f\u4e00\u7d22\u5f15
CREATE UNIQUE INDEX idx_reader_phone
ON reader(phone);
3.\u521b\u5efa\u590d\u5408\u7d22\u5f15
CREATE INDEX idx_borrow_rno_bno
ON borrow(rno,bno);
\u67e5\u770b\u7d22\u5f15
SHOW INDEX FROM book;
SHOW INDEX FROM reader;
SHOW INDEX FROM borrow;
\u5220\u9664\u7d22\u5f15
DROP INDEX idx_book_bname ON book;
DROP INDEX idx_reader_phone ON reader;
DROP INDEX idx_borrow_rno_bno ON borrow;<\/pre>\n\n\n\n13.\u6570\u636e\u5b8c\u6574\u6027\u7ea6\u675f\u9a8c\u8bc1\u4e0e\u7ea7\u8054\u64cd\u4f5c<\/h2>\n\n\n\n1.\u5b9e\u4f53\u5b8c\u6574\u6027\u9a8c\u8bc1\uff1a\u4e3b\u952e\u4e0d\u80fd\u4e3a\u7a7a
INSERT INTO book(bno,bname,author,press,pubyear,stock)
VALUES(NULL,'\u6d4b\u8bd5\u4e66','\u6d4b\u8bd5\u4f5c\u8005','\u6d4b\u8bd5\u51fa\u7248\u793e',2020,1);
\u8bf4\u660e\uff1a
bno \u662f book \u8868\u4e3b\u952e\uff0c\u4e3b\u952e\u4e0d\u80fd\u4e3a\u7a7a\uff0c\u56e0\u6b64\u63d2\u5165\u5931\u8d25\u3002
2.\u53c2\u7167\u5b8c\u6574\u6027\u9a8c\u8bc1\uff1a\u63d2\u5165\u4e0d\u5b58\u5728\u7684\u56fe\u4e66\u7f16\u53f7
INSERT INTO borrow(rno,bno,borrowdate,returndate,actualdate)
VALUES('R2024001','B999','2025-05-01','2025-05-15',NULL);
\u8bf4\u660e\uff1a
B999 \u5728 book \u8868\u4e2d\u4e0d\u5b58\u5728\uff0cborrow.bno \u662f\u5916\u952e\uff0c\u56e0\u6b64\u8fdd\u53cd\u53c2\u7167\u5b8c\u6574\u6027\u3002
3.\u7528\u6237\u5b9a\u4e49\u5b8c\u6574\u6027\u9a8c\u8bc1\uff1a\u5e93\u5b58\u4e0d\u80fd\u5c0f\u4e8e0
UPDATE book
SET stock = -1
WHERE bno = 'B001';
\u8bf4\u660e\uff1a
stock \u5b57\u6bb5\u8bbe\u7f6e\u4e86 CHECK(stock>=0)\uff0c\u5e93\u5b58\u4e0d\u80fd\u4e3a\u8d1f\u6570\u3002
4.\u7528\u6237\u5b9a\u4e49\u5b8c\u6574\u6027\u9a8c\u8bc1\uff1a\u5e93\u5b58\u4e0d\u80fd\u5c0f\u4e8e0
UPDATE book
SET stock = -1
WHERE bno = 'B001';
\u8bf4\u660e\uff1a
stock \u5b57\u6bb5\u8bbe\u7f6e\u4e86 CHECK(stock>=0)\uff0c\u5e93\u5b58\u4e0d\u80fd\u4e3a\u8d1f\u6570\u3002
5.ON UPDATE CASCADE \u6d4b\u8bd5
UPDATE reader
SET rno = 'R2024999'
WHERE rno = 'R2024003';
SELECT * FROM borrow
WHERE rno = 'R2024999';
\u8bf4\u660e\uff1a
reader.rno \u66f4\u65b0\u540e\uff0cborrow \u8868\u4e2d\u5bf9\u5e94\u7684\u5916\u952e rno \u4f1a\u81ea\u52a8\u540c\u6b65\u66f4\u65b0\u3002<\/pre>\n\n\n\n14.\u89e6\u53d1\u5668<\/h2>\n\n\n\n\u51c6\u5907\uff1a\u5220\u9664\u65e7\u89e6\u53d1\u5668
DROP TRIGGER IF EXISTS trg_borrow_before_insert;
DROP TRIGGER IF EXISTS trg_return_after_update;
DROP TRIGGER IF EXISTS trg_reader_before_delete;
\u521b\u5efa\u5220\u9664\u8bfb\u8005\u65e5\u5fd7\u8868
CREATE TABLE reader_delete_log(
logid INT AUTO_INCREMENT PRIMARY KEY,
rno CHAR(12),
rname VARCHAR(20),
dept VARCHAR(40),
delete_time DATETIME DEFAULT CURRENT_TIMESTAMP
);
1.\u501f\u4e66\u65f6\u81ea\u52a8\u51cf\u5c11\u5e93\u5b58
DELIMITER \/\/
CREATE TRIGGER trg_borrow_before_insert
BEFORE INSERT ON borrow
FOR EACH ROW
BEGIN
DECLARE v_stock INT;
SELECT stock INTO v_stock
FROM book
WHERE bno = NEW.bno;
IF v_stock <= 0 THEN
SIGNAL SQLSTATE '45000'
SET MESSAGE_TEXT = '\u5e93\u5b58\u4e0d\u8db3\uff0c\u4e0d\u80fd\u501f\u4e66';
ELSE
UPDATE book
SET stock = stock - 1
WHERE bno = NEW.bno;
END IF;
END \/\/
DELIMITER ;
\u6d4b\u8bd5\uff1a
SELECT stock FROM book WHERE bno='B003';
INSERT INTO borrow(rno,bno,borrowdate,returndate,actualdate)
VALUES('R2024002','B003','2025-05-01','2025-05-15',NULL);
SELECT stock FROM book WHERE bno='B003';
2.\u8fd8\u4e66\u65f6\u81ea\u52a8\u589e\u52a0\u5e93\u5b58\u5e76\u8ba1\u7b97\u7f5a\u6b3e
DELIMITER \/\/
CREATE TRIGGER trg_return_after_update
AFTER UPDATE ON borrow
FOR EACH ROW
BEGIN
IF OLD.actualdate IS NULL AND NEW.actualdate IS NOT NULL THEN
UPDATE book
SET stock = stock + 1
WHERE bno = NEW.bno;
UPDATE borrow
SET fine =
CASE
WHEN NEW.actualdate > NEW.returndate
THEN DATEDIFF(NEW.actualdate, NEW.returndate) * 1
ELSE 0
END
WHERE borrowid = NEW.borrowid;
END IF;
END \/\/
DELIMITER ;
\u6d4b\u8bd5\uff1a
UPDATE borrow
SET actualdate = '2025-05-18'
WHERE rno='R2024002'
AND bno='B003'
AND borrowdate='2025-05-01';
SELECT * FROM borrow
WHERE rno='R2024002'
AND bno='B003';
SELECT stock FROM book WHERE bno='B003';
3.\u5220\u9664\u8bfb\u8005\u524d\u8bb0\u5f55\u65e5\u5fd7
DELIMITER \/\/
CREATE TRIGGER trg_reader_before_delete
BEFORE DELETE ON reader
FOR EACH ROW
BEGIN
INSERT INTO reader_delete_log(rno,rname,dept)
VALUES(OLD.rno, OLD.rname, OLD.dept);
END \/\/
DELIMITER ;
\u6d4b\u8bd5\uff1a
INSERT INTO reader
VALUES('R2024888','\u65e5\u5fd7\u6d4b\u8bd5','\u7537','\u6d4b\u8bd5\u5b66\u9662','\u65e0');
DELETE FROM reader
WHERE rno='R2024888';
SELECT * FROM reader_delete_log;<\/pre>\n\n\n\n15.\u6570\u636e\u5b89\u5168\u6027<\/h2>\n\n\n\n1.\u521b\u5efa\u7528\u6237\u5e76\u6388\u4e88\u67e5\u8be2\u6743\u9650
CREATE USER 'lib_user1'@'localhost'
IDENTIFIED BY '123456';
GRANT SELECT
ON library_db.book
TO 'lib_user1'@'localhost';
\u67e5\u770b\u6743\u9650\uff1a
SHOW GRANTS FOR 'lib_user1'@'localhost';
2.\u6388\u4e88\u6743\u9650\u5e76\u5141\u8bb8\u8f6c\u6388\u6743
GRANT SELECT, INSERT
ON library_db.reader
TO 'lib_user1'@'localhost'
WITH GRANT OPTION;
\u8bf4\u660e\uff1a
WITH GRANT OPTION \u8868\u793a\u8be5\u7528\u6237\u53ef\u4ee5\u5c06\u81ea\u5df1\u62e5\u6709\u7684\u6743\u9650\u518d\u6388\u4e88\u5176\u4ed6\u7528\u6237\u3002
3.\u56de\u6536\u6743\u9650
REVOKE INSERT
ON library_db.reader
FROM 'lib_user1'@'localhost';
4.\u521b\u5efa\u89d2\u8272\u5e76\u6388\u6743
CREATE ROLE 'reader_role';
GRANT SELECT
ON library_db.*
TO 'reader_role';
CREATE USER 'lib_user2'@'localhost'
IDENTIFIED BY '123456';
GRANT 'reader_role'
TO 'lib_user2'@'localhost';
SET DEFAULT ROLE 'reader_role'
TO 'lib_user2'@'localhost';<\/pre>\n\n\n\n16.\u89c6\u56fe\u4e0e\u6d3e\u751f\u8868<\/h2>\n\n\n\n1.\u5e26\u805a\u5408\u51fd\u6570\u7684\u89c6\u56fe\uff1a\u7edf\u8ba1\u6bcf\u4e2a\u8bfb\u8005\u501f\u9605\u6b21\u6570
CREATE VIEW v_reader_borrow_count AS
SELECT r.rno, r.rname, COUNT(br.borrowid) AS borrow_count
FROM reader r
LEFT JOIN borrow br
ON r.rno = br.rno
GROUP BY r.rno, r.rname;
\u67e5\u8be2\uff1a
SELECT * FROM v_reader_borrow_count;
2.\u6d3e\u751f\u8868\uff1a\u67e5\u8be2\u501f\u9605\u6b21\u6570\u5927\u4e8e1\u7684\u8bfb\u8005
SELECT *
FROM (
SELECT rno, COUNT(*) AS borrow_count
FROM borrow
GROUP BY rno
) AS t
WHERE t.borrow_count > 1;
3.WITH \u5b50\u53e5\u7edf\u8ba1\u6bcf\u4f4d\u8bfb\u8005\u501f\u9605\u6570\u91cf
WITH reader_count AS (
SELECT rno, COUNT(*) AS total
FROM borrow
GROUP BY rno
)
SELECT r.rno, r.rname, rc.total
FROM reader r
LEFT JOIN reader_count rc
ON r.rno = rc.rno;
4.WITH \u5b50\u53e5\uff1a\u67e5\u8be2\u672a\u5f52\u8fd8\u56fe\u4e66
WITH unreturned AS (
SELECT br.borrowid, r.rname, b.bname,
br.borrowdate, br.returndate
FROM borrow br
JOIN reader r ON br.rno = r.rno
JOIN book b ON br.bno = b.bno
WHERE br.actualdate IS NULL
)
SELECT * FROM unreturned;<\/pre>\n\n\n\n17.\u6269\u5c55\u601d\u8003<\/h2>\n\n\n\n\n- \u5982\u4f55\u5904\u7406\u5206\u7c7b\u5b9e\u4f53\u7684\u81ea\u5173\u8054\uff1f<\/li>\n<\/ol>\n\n\n\n
\u5206\u7c7b\u5b9e\u4f53\u5b58\u5728\u201c\u4e0a\u7ea7\u5206\u7c7b\u201d\u548c\u201c\u4e0b\u7ea7\u5206\u7c7b\u201d\u7684\u5173\u7cfb\uff0c\u56e0\u6b64\u53ef\u4ee5\u5728 category \u8868\u4e2d\u8bbe\u7f6e parentid \u5b57\u6bb5\u3002
category(
cid,
cname,
parentid
)
\u5176\u4e2d cid \u662f\u5206\u7c7b\u7f16\u53f7\uff0cparentid \u662f\u4e0a\u7ea7\u5206\u7c7b\u7f16\u53f7\uff0c\u540c\u65f6 parentid \u4e5f\u662f\u6307\u5411 category.cid \u7684\u5916\u952e\u3002
\u5982\u679c\u67d0\u5206\u7c7b\u6ca1\u6709\u4e0a\u7ea7\u5206\u7c7b\uff0c\u5219 parentid \u53ef\u4ee5\u4e3a\u7a7a\u3002
\u8fd9\u79cd\u8bbe\u8ba1\u53ef\u4ee5\u8868\u793a\u6811\u5f62\u7ed3\u6784\uff0c\u4f8b\u5982\uff1a
\u56fe\u4e66
\u251c\u2500\u2500 \u8ba1\u7b97\u673a
\u2502 \u251c\u2500\u2500 \u6570\u636e\u5e93
\u2502 \u2514\u2500\u2500 \u7f51\u7edc\u6280\u672f
\u2514\u2500\u2500 \u6587\u5b66
\u2514\u2500\u2500 \u79d1\u5e7b\u5c0f\u8bf4<\/pre>\n\n\n\n
\n\n\n\n2. \u501f\u9605\u5173\u7cfb\u662f\u5426\u53ef\u80fd\u5b58\u5728\u6570\u636e\u5197\u4f59\uff1f<\/h2>\n\n\n\n\u501f\u9605\u8868\u5982\u679c\u53ea\u4fdd\u5b58 rno\u3001bno\u3001borrowdate\u3001returndate\u3001actualdate \u7b49\u4fe1\u606f\uff0c\u5219\u5197\u4f59\u8f83\u5c11\u3002
\u4f46\u662f\u5982\u679c\u5728 borrow \u8868\u4e2d\u540c\u65f6\u4fdd\u5b58\u8bfb\u8005\u59d3\u540d rname\u3001\u56fe\u4e66\u540d\u79f0 bname\u3001\u51fa\u7248\u793e press \u7b49\u4fe1\u606f\uff0c\u5c31\u4f1a\u4ea7\u751f\u6570\u636e\u5197\u4f59\u3002
\u4f8b\u5982\uff1a
borrow(borrowid, rno, rname, bno, bname, borrowdate)
\u5176\u4e2d rname \u4f9d\u8d56 rno\uff0cbname \u4f9d\u8d56 bno\uff0c\u800c\u4e0d\u662f\u76f4\u63a5\u4f9d\u8d56 borrowid\uff0c\u4f1a\u4ea7\u751f\u4f20\u9012\u4f9d\u8d56\u3002
\u89c4\u8303\u5316\u65b9\u6848\uff1a
\u5c06\u8bfb\u8005\u4fe1\u606f\u4fdd\u5b58\u5728 reader \u8868\uff1b
\u5c06\u56fe\u4e66\u4fe1\u606f\u4fdd\u5b58\u5728 book \u8868\uff1b
borrow \u8868\u53ea\u4fdd\u5b58\u8bfb\u8005\u8bc1\u53f7\u548c\u56fe\u4e66\u7f16\u53f7\u4f5c\u4e3a\u5916\u952e\u3002<\/pre>\n\n\n\n
\n\n\n\n3. \u5982\u4f55\u9632\u6b62\u5e93\u5b58\u4e3a\u8d1f\u6570\uff1f<\/h2>\n\n\n\n\u53ef\u4ee5\u4ece\u4e24\u4e2a\u65b9\u9762\u9632\u6b62\u5e93\u5b58\u4e3a\u8d1f\u6570\uff1a
\u7b2c\u4e00\uff0c\u5728 book \u8868\u4e2d\u8bbe\u7f6e CHECK(stock >= 0) \u7ea6\u675f\uff0c\u4fdd\u8bc1\u5e93\u5b58\u4e0d\u80fd\u5c0f\u4e8e0\u3002
\u7b2c\u4e8c\uff0c\u5728\u501f\u4e66\u89e6\u53d1\u5668\u4e2d\u5224\u65ad\u5e93\u5b58\u6570\u91cf\u3002
\u5f53\u63d2\u5165 borrow \u501f\u9605\u8bb0\u5f55\u65f6\uff0c\u5148\u67e5\u8be2\u56fe\u4e66\u5e93\u5b58\u3002
\u5982\u679c\u5e93\u5b58\u5c0f\u4e8e\u7b49\u4e8e0\uff0c\u5219\u4f7f\u7528 SIGNAL \u629b\u51fa\u9519\u8bef\uff0c\u963b\u6b62\u501f\u4e66\u64cd\u4f5c\uff1b
\u5982\u679c\u5e93\u5b58\u5927\u4e8e0\uff0c\u5219\u5141\u8bb8\u501f\u9605\uff0c\u5e76\u81ea\u52a8\u5c06\u5e93\u5b58\u51cf1\u3002
\u8fd9\u6837\u53ef\u4ee5\u4fdd\u8bc1\u501f\u4e66\u65f6\u4e0d\u4f1a\u51fa\u73b0\u5e93\u5b58\u4e3a\u8d1f\u6570\u7684\u60c5\u51b5\u3002<\/pre>\n\n\n\n
\n\n\n\n4. \u9884\u7ea6\u56fe\u4e66\u529f\u80fd\u9700\u8981\u589e\u52a0\u54ea\u4e9b\u5b9e\u4f53\u548c\u5173\u7cfb\uff1f<\/h2>\n\n\n\n\u5982\u679c\u7cfb\u7edf\u652f\u6301\u9884\u7ea6\u56fe\u4e66\u529f\u80fd\uff0c\u53ef\u4ee5\u589e\u52a0 reservation \u9884\u7ea6\u8868\u3002
reservation(
reserveid,
rno,
bno,
reservedate,
status
)
\u5176\u4e2d\uff1a
reserveid \u8868\u793a\u9884\u7ea6\u7f16\u53f7\uff1b
rno \u662f\u8bfb\u8005\u8bc1\u53f7\uff0c\u5916\u952e\u5f15\u7528 reader.rno\uff1b
bno \u662f\u56fe\u4e66\u7f16\u53f7\uff0c\u5916\u952e\u5f15\u7528 book.bno\uff1b
reservedate \u8868\u793a\u9884\u7ea6\u65e5\u671f\uff1b
status \u8868\u793a\u9884\u7ea6\u72b6\u6001\uff0c\u5982\u201c\u9884\u7ea6\u4e2d\u201d\u201c\u5df2\u53d6\u6d88\u201d\u201c\u5df2\u5b8c\u6210\u201d\u3002
\u65b0\u589e\u5173\u7cfb\uff1a
\u4e00\u4e2a\u8bfb\u8005\u53ef\u4ee5\u9884\u7ea6\u591a\u672c\u56fe\u4e66\uff1b
\u4e00\u672c\u56fe\u4e66\u53ef\u4ee5\u88ab\u591a\u4e2a\u8bfb\u8005\u9884\u7ea6\uff1b
\u8bfb\u8005\u548c\u56fe\u4e66\u4e4b\u95f4\u901a\u8fc7 reservation \u8868\u5f62\u6210 m:n \u8054\u7cfb\u3002<\/pre>\n\n\n\n
\n\n\n\n5. \u4e3a\u4ec0\u4e48\u9075\u5faa\u6700\u5c0f\u6743\u9650\u539f\u5219\uff1f<\/h2>\n\n\n\n\u6700\u5c0f\u6743\u9650\u539f\u5219\u662f\u6307\u53ea\u7ed9\u7528\u6237\u5b8c\u6210\u5de5\u4f5c\u6240\u5fc5\u9700\u7684\u6743\u9650\uff0c\u4e0d\u6388\u4e88\u591a\u4f59\u6743\u9650\u3002
\u5728\u672c\u5b9e\u9a8c\u4e2d\uff0c\u5982\u679c\u67d0\u7528\u6237\u53ea\u8d1f\u8d23\u67e5\u8be2\u56fe\u4e66\u4fe1\u606f\uff0c\u5219\u53ea\u6388\u4e88 SELECT \u6743\u9650\u5373\u53ef\uff0c\u4e0d\u5e94\u8be5\u6388\u4e88 INSERT\u3001UPDATE\u3001DELETE \u7b49\u6743\u9650\u3002
\u4f8b\u5982\uff1a
GRANT SELECT ON library_db.book TO 'lib_user1'@'localhost';
\u8fd9\u6837\u53ef\u4ee5\u9632\u6b62\u7528\u6237\u8bef\u5220\u3001\u8bef\u6539\u6570\u636e\uff0c\u63d0\u9ad8\u6570\u636e\u5e93\u5b89\u5168\u6027\u3002
\u5982\u679c\u540e\u7eed\u4e0d\u518d\u9700\u8981\u67d0\u9879\u6743\u9650\uff0c\u8fd8\u53ef\u4ee5\u4f7f\u7528 REVOKE \u56de\u6536\u6743\u9650\u3002<\/pre>\n\n\n\n
\n\n\n\n6. \u5e76\u53d1\u501f\u9605\u5e93\u5b58\u4ec5\u52691\u672c\u7684\u56fe\u4e66\u4f1a\u4ea7\u751f\u4ec0\u4e48\u95ee\u9898\uff1f\u5982\u4f55\u89e3\u51b3\uff1f<\/h2>\n\n\n\n\u5f53\u591a\u7528\u6237\u540c\u65f6\u501f\u9605\u540c\u4e00\u672c\u5e93\u5b58\u4ec5\u52691\u672c\u7684\u56fe\u4e66\u65f6\uff0c\u53ef\u80fd\u51fa\u73b0\u8d85\u5356\u95ee\u9898\u3002
\u4f8b\u5982\u4e24\u4e2a\u7528\u6237\u540c\u65f6\u8bfb\u53d6\u5e93\u5b58 stock=1\uff0c\u90fd\u8ba4\u4e3a\u53ef\u4ee5\u501f\u9605\uff0c\u7136\u540e\u540c\u65f6\u63d2\u5165\u501f\u9605\u8bb0\u5f55\u5e76\u6267\u884c\u5e93\u5b58\u51cf1\uff0c\u6700\u7ec8\u53ef\u80fd\u5bfc\u81f4\u5e93\u5b58\u5f02\u5e38\u6216\u51fa\u73b0\u8d85\u989d\u501f\u9605\u3002
\u89e3\u51b3\u65b9\u6cd5\uff1a
1. \u4f7f\u7528\u4e8b\u52a1\u4fdd\u8bc1\u501f\u4e66\u64cd\u4f5c\u7684\u539f\u5b50\u6027\uff1b
2. \u4f7f\u7528 SELECT ... FOR UPDATE \u5bf9\u56fe\u4e66\u5e93\u5b58\u8bb0\u5f55\u52a0\u884c\u7ea7\u9501\uff1b
3. \u5728\u89e6\u53d1\u5668\u4e2d\u5224\u65ad\u5e93\u5b58\u662f\u5426\u5927\u4e8e0\uff1b
4. \u7ed9 stock \u5b57\u6bb5\u8bbe\u7f6e CHECK(stock >= 0) \u7ea6\u675f\u3002
\u793a\u4f8b\uff1a
START TRANSACTION;
SELECT stock
FROM book
WHERE bno='B001'
FOR UPDATE;
UPDATE book
SET stock = stock - 1
WHERE bno='B001'
AND stock > 0;
INSERT INTO borrow(rno,bno,borrowdate,returndate)
VALUES('R2024001','B001','2025-05-01','2025-05-15');
COMMIT;
\u8fd9\u6837\u53ef\u4ee5\u907f\u514d\u591a\u4e2a\u7528\u6237\u540c\u65f6\u4fee\u6539\u5e93\u5b58\u5bfc\u81f4\u6570\u636e\u4e0d\u4e00\u81f4\u3002<\/pre>\n\n\n\n
\n\n\n\n\u5b9e\u9a8c\u603b\u7ed3<\/h1>\n\n\n\n \u901a\u8fc7\u672c\u6b21\u56fe\u4e66\u501f\u9605\u7ba1\u7406\u7cfb\u7edf\u7efc\u5408\u5b9e\u9a8c\uff0c\u6211\u7cfb\u7edf\u5730\u5b8c\u6210\u4e86\u6570\u636e\u5e93\u8bbe\u8ba1\u4e0e\u5b9e\u73b0\u7684\u5168\u8fc7\u7a0b\u3002\u5b9e\u9a8c\u4ece\u9700\u6c42\u5206\u6790\u5f00\u59cb\uff0c\u9010\u6b65\u5b8c\u6210 E-R \u56fe\u8bbe\u8ba1\u3001\u5173\u7cfb\u6a21\u5f0f\u8f6c\u6362\u3001\u7269\u7406\u8868\u7ed3\u6784\u8bbe\u8ba1\u3001\u6570\u636e\u63d2\u5165\u3001\u67e5\u8be2\u64cd\u4f5c\u3001\u89c6\u56fe\u3001\u7d22\u5f15\u3001\u5b8c\u6574\u6027\u7ea6\u675f\u3001\u89e6\u53d1\u5668\u548c\u6743\u9650\u7ba1\u7406\u7b49\u5185\u5bb9\uff0c\u4f7f\u6211\u5bf9\u6570\u636e\u5e93\u5e94\u7528\u7cfb\u7edf\u7684\u8bbe\u8ba1\u6d41\u7a0b\u6709\u4e86\u66f4\u52a0\u5b8c\u6574\u7684\u8ba4\u8bc6\u3002
\u200b
\u5728\u5b9e\u9a8c\u8fc7\u7a0b\u4e2d\uff0c\u6211\u9996\u5148\u6839\u636e\u56fe\u4e66\u9986\u4e1a\u52a1\u9700\u6c42\u5206\u6790\u51fa\u56fe\u4e66\u3001\u8bfb\u8005\u3001\u501f\u9605\u3001\u51fa\u7248\u793e\u3001\u5206\u7c7b\u7b49\u5b9e\u4f53\uff0c\u5e76\u660e\u786e\u4e86\u5b83\u4eec\u4e4b\u95f4\u7684\u8054\u7cfb\u7c7b\u578b\u3002\u4f8b\u5982\uff0c\u51fa\u7248\u793e\u4e0e\u56fe\u4e66\u4e4b\u95f4\u662f\u4e00\u5bf9\u591a\u5173\u7cfb\uff0c\u5206\u7c7b\u4e0e\u56fe\u4e66\u4e4b\u95f4\u662f\u4e00\u5bf9\u591a\u5173\u7cfb\uff0c\u8bfb\u8005\u4e0e\u56fe\u4e66\u4e4b\u95f4\u901a\u8fc7\u501f\u9605\u8868\u5f62\u6210\u591a\u5bf9\u591a\u5173\u7cfb\u3002\u901a\u8fc7 E-R \u56fe\u8bbe\u8ba1\uff0c\u6211\u8fdb\u4e00\u6b65\u7406\u89e3\u4e86\u6982\u5ff5\u7ed3\u6784\u8bbe\u8ba1\u5728\u6570\u636e\u5e93\u5f00\u53d1\u4e2d\u7684\u91cd\u8981\u4f5c\u7528\u3002
\u200b
\u5728\u903b\u8f91\u7ed3\u6784\u8bbe\u8ba1\u9636\u6bb5\uff0c\u6211\u5c06 E-R \u56fe\u8f6c\u6362\u4e3a\u5173\u7cfb\u6a21\u5f0f\uff0c\u5e76\u5206\u6790\u5404\u8868\u662f\u5426\u6ee1\u8db3\u7b2c\u4e09\u8303\u5f0f\u3002\u901a\u8fc7\u89c4\u8303\u5316\u8bbe\u8ba1\uff0c\u907f\u514d\u4e86\u5728\u501f\u9605\u8868\u4e2d\u91cd\u590d\u4fdd\u5b58\u8bfb\u8005\u59d3\u540d\u3001\u56fe\u4e66\u540d\u79f0\u7b49\u4fe1\u606f\uff0c\u51cf\u5c11\u4e86\u6570\u636e\u5197\u4f59\uff0c\u63d0\u9ad8\u4e86\u6570\u636e\u4e00\u81f4\u6027\u3002\u5728\u7269\u7406\u8bbe\u8ba1\u9636\u6bb5\uff0c\u6211\u4f7f\u7528 SQL \u521b\u5efa\u6570\u636e\u5e93\u548c\u6570\u636e\u8868\uff0c\u8bbe\u7f6e\u4e86\u4e3b\u952e\u3001\u5916\u952e\u3001\u975e\u7a7a\u3001\u9ed8\u8ba4\u503c\u548c CHECK \u7ea6\u675f\uff0c\u5bf9\u5b9e\u4f53\u5b8c\u6574\u6027\u3001\u53c2\u7167\u5b8c\u6574\u6027\u548c\u7528\u6237\u5b9a\u4e49\u5b8c\u6574\u6027\u6709\u4e86\u66f4\u6df1\u523b\u7684\u7406\u89e3\u3002
\u200b
\u5728\u6570\u636e\u64cd\u4f5c\u90e8\u5206\uff0c\u6211\u7ec3\u4e60\u4e86 INSERT\u3001UPDATE\u3001DELETE \u548c SELECT \u8bed\u53e5\uff0c\u5e76\u5b8c\u6210\u4e86\u57fa\u7840\u67e5\u8be2\u3001\u805a\u5408\u67e5\u8be2\u3001\u591a\u8868\u8fde\u63a5\u67e5\u8be2\u3001\u5d4c\u5957\u67e5\u8be2\u548c\u96c6\u5408\u67e5\u8be2\u7b49\u5185\u5bb9\u3002\u901a\u8fc7\u8fd9\u4e9b\u7ec3\u4e60\uff0c\u6211\u638c\u63e1\u4e86 SQL \u67e5\u8be2\u8bed\u53e5\u7684\u5e38\u89c1\u5199\u6cd5\uff0c\u5c24\u5176\u662f\u591a\u8868\u8fde\u63a5\u548c\u5d4c\u5957\u67e5\u8be2\u7684\u4f7f\u7528\u65b9\u6cd5\u3002\u5b9e\u9a8c\u4e2d\u8fd8\u521b\u5efa\u4e86\u89c6\u56fe\u548c\u7d22\u5f15\uff0c\u7406\u89e3\u4e86\u89c6\u56fe\u53ef\u4ee5\u7b80\u5316\u590d\u6742\u67e5\u8be2\uff0c\u7d22\u5f15\u53ef\u4ee5\u63d0\u9ad8\u67e5\u8be2\u6548\u7387\uff0c\u4f46\u4e5f\u4f1a\u589e\u52a0\u7ef4\u62a4\u6210\u672c\u3002
\u200b
\u5728\u89e6\u53d1\u5668\u90e8\u5206\uff0c\u6211\u5b9e\u73b0\u4e86\u501f\u4e66\u81ea\u52a8\u51cf\u5c11\u5e93\u5b58\u3001\u8fd8\u4e66\u81ea\u52a8\u589e\u52a0\u5e93\u5b58\u5e76\u8ba1\u7b97\u7f5a\u6b3e\u3001\u5220\u9664\u8bfb\u8005\u524d\u8bb0\u5f55\u65e5\u5fd7\u7b49\u529f\u80fd\u3002\u901a\u8fc7\u89e6\u53d1\u5668\u5b9e\u9a8c\uff0c\u6211\u8ba4\u8bc6\u5230\u6570\u636e\u5e93\u4e0d\u4ec5\u53ef\u4ee5\u5b58\u50a8\u6570\u636e\uff0c\u8fd8\u53ef\u4ee5\u5728\u7279\u5b9a\u64cd\u4f5c\u53d1\u751f\u65f6\u81ea\u52a8\u6267\u884c\u4e00\u4e9b\u4e1a\u52a1\u903b\u8f91\u3002\u5b9e\u9a8c\u8fc7\u7a0b\u4e2d\u4e5f\u9047\u5230\u4e86\u4e00\u4e9b\u95ee\u9898\uff0c\u4f8b\u5982\u5916\u952e\u7ea6\u675f\u5bfc\u81f4\u6570\u636e\u65e0\u6cd5\u5220\u9664\u3001CHECK \u7ea6\u675f\u63d2\u5165\u5931\u8d25\u3001\u89e6\u53d1\u5668\u8bed\u6cd5\u9519\u8bef\u7b49\u3002\u901a\u8fc7\u67e5\u770b\u9519\u8bef\u4fe1\u606f\u3001\u4fee\u6539 SQL \u8bed\u53e5\u548c\u53cd\u590d\u6d4b\u8bd5\uff0c\u6700\u7ec8\u89e3\u51b3\u4e86\u8fd9\u4e9b\u95ee\u9898\u3002
\u200b
\u901a\u8fc7\u672c\u6b21\u5b9e\u9a8c\uff0c\u6211\u4e0d\u4ec5\u5de9\u56fa\u4e86\u6570\u636e\u5e93\u7406\u8bba\u77e5\u8bc6\uff0c\u4e5f\u63d0\u9ad8\u4e86 SQL \u7f16\u5199\u80fd\u529b\u548c\u6570\u636e\u5e93\u8c03\u8bd5\u80fd\u529b\u3002\u4eca\u540e\u5728\u8bbe\u8ba1\u6570\u636e\u5e93\u7cfb\u7edf<\/pre>\n","protected":false},"excerpt":{"rendered":"\u6570\u636e\u5e93\u7efc\u5408\u5b9e\u9a8c 1.\u9700\u6c42\u5206\u6790 \u67d0\u5927\u578b\u56fe\u4e66\u9986\u9700\u8981\u5f00\u53d1\u4e00\u5957\u6570\u5b57\u5316\u501f\u9605\u7ba1\u7406\u7cfb\u7edf\uff0c\u4e3b\u8981\u4e1a\u52a1\u9700\u6c42\u5982\u4e0b\uff1a \u56fe\u4e66\u4fe1\u606f\uff1a\u8bb0\u5f55\u56fe […]<\/p>\n","protected":false},"author":1,"featured_media":448,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[9],"tags":[],"class_list":["post-446","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-wenzhang"],"_links":{"self":[{"href":"https:\/\/fg2025.cn\/index.php\/wp-json\/wp\/v2\/posts\/446","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/fg2025.cn\/index.php\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/fg2025.cn\/index.php\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/fg2025.cn\/index.php\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/fg2025.cn\/index.php\/wp-json\/wp\/v2\/comments?post=446"}],"version-history":[{"count":0,"href":"https:\/\/fg2025.cn\/index.php\/wp-json\/wp\/v2\/posts\/446\/revisions"}],"wp:attachment":[{"href":"https:\/\/fg2025.cn\/index.php\/wp-json\/wp\/v2\/media?parent=446"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/fg2025.cn\/index.php\/wp-json\/wp\/v2\/categories?post=446"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/fg2025.cn\/index.php\/wp-json\/wp\/v2\/tags?post=446"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}
('B001','\u6570\u636e\u5e93\u7cfb\u7edf\u6982\u8bba','\u738b\u73ca',
'\u9ad8\u7b49\u6559\u80b2\u51fa\u7248\u793e',2018,5),
\u200b
('B002','C\u7a0b\u5e8f\u8bbe\u8ba1\u8bed\u8a00','K&R',
'\u673a\u68b0\u5de5\u4e1a\u51fa\u7248\u793e',2015,3),
\u200b
('B003','\u4e09\u4f53','\u5218\u6148\u6b23',
'\u91cd\u5e86\u51fa\u7248\u793e',2010,8),
\u200b
('B004','\u8ba1\u7b97\u673a\u7f51\u7edc','\u8c22\u5e0c\u4ec1',
'\u7535\u5b50\u5de5\u4e1a\u51fa\u7248\u793e',2018,4);
\u200b
INSERT INTO reader
VALUES
('R2024001','\u5f20\u660e','\u7537',
'\u8ba1\u7b97\u673a\u5b66\u9662','13812345678',
'zhangming@qq.com'),
\u200b
('R2024002','\u674e\u82b3','\u5973',
'\u4fe1\u606f\u5b66\u9662','13912345678',
'lifang@qq.com'),
\u200b
('R2024003','\u738b\u78ca','\u7537',
'\u6587\u5b66\u9662','13612345678',
'wanglei@qq.com');
\u200b
INSERT INTO borrow VALUES
(1,'R2024001','B001',
'2025-03-01',
'2025-03-15',
'2025-03-14'),
(2,'R2024001','B003',
'2025-03-10',
'2025-03-24',
NULL),
(3,'R2024002','B002',
'2025-04-01',
'2025-04-15',
NULL),
(4,'R2024003','B004',
'2025-03-20',
'2025-04-03',
'2025-04-05');<\/pre>\n\n\n\n
4.1 \u8bbe\u8ba1\u8fdd\u53cd\u5916\u952e\u7ea6\u675f\u548ccheck\u7ea6\u675f\u5e76\u89e3\u91ca<\/h3>\n\n\n\n INSERT INTO borrow(
rno,bno,
borrowdate,
returndate)
VALUES(
'R999999',
'B001',
'2025-05-01',
'2025-05-15');
\u200b
\u9519\u8bef\uff1aCannot add or update a child row:
a foreign key constraint fails
\u200b
\u539f\u56e0\uff1aR999999\u5728reader\u8868\u4e2d\u4e0d\u5b58\u5728\uff0c
\u8fdd\u53cd\u53c2\u7167\u5b8c\u6574\u6027\u7ea6\u675f\u3002
\u200b
\u8fdd\u53cdcheck
INSERT INTO reader
VALUES(
'R2024004',
'\u8d75\u654f',
'\u672a\u77e5',
'\u827a\u672f\u5b66\u9662',
'13712345678');
\u200b
\u9519\u8bef\uff1aCheck constraint violated
\u200b
\u539f\u56e0\uff1arsex\u5b57\u6bb5\u53ea\u80fd\u53d6
\u7537 \u6216 \u5973\uff0c
\u56e0\u6b64\u8fdd\u53cdCHECK\u7ea6\u675f\u3002<\/pre>\n\n\n\n5.\u6570\u636e\u67e5\u8be2\uff08DQL-\u57fa\u7840\u67e5\u8be2\uff09<\/h2>\n\n\n\n 1.select\u67e5\u8be2\u5168\u90e8\u56fe\u4e66\u4fe1\u606f
select * from book;
2.\u67e5\u8be2\u5e93\u5b58\u5927\u4e8e3\u7684\u56fe\u4e66
SELECT bno,bname,stock
FROM book
WHERE stock > 3;
3.\u67e5\u8be22018\u5e74\u51fa\u7248\u4e14\u5e93\u5b58\u4e0d\u5c11\u4e8e4\u672c\u7684\u56fe\u4e66
SELECT bno,bname,pubyear,stock
FROM book
WHERE pubyear = 2018 AND stock >= 4;
4.\u67e5\u8be22015\u5e74\u81f32018\u5e74\u51fa\u7248\u7684\u56fe\u4e66
SELECT bno,bname,pubyear
FROM book
WHERE pubyear BETWEEN 2015 AND 2018;
5.\u67e5\u8be2\u51fa\u7248\u793e\u4e3a\u201c\u91cd\u5e86\u51fa\u7248\u793e\u201d\u6216\u201c\u9ad8\u7b49\u6559\u80b2\u51fa\u7248\u793e\u201d\u7684\u56fe\u4e66
SELECT bno,bname,press
FROM book
WHERE press IN('\u91cd\u5e86\u51fa\u7248\u793e','\u9ad8\u7b49\u6559\u80b2\u51fa\u7248\u793e');
6.\u67e5\u8be2\u4e66\u540d\u4e2d\u5305\u542b\u201c\u8ba1\u7b97\u673a\u201d\u7684\u56fe\u4e66
SELECT bno,bname
FROM book
WHERE bname LIKE '%\u8ba1\u7b97\u673a%';
7.\u67e5\u8be2\u5c1a\u672a\u5f52\u8fd8\u7684\u501f\u9605\u8bb0\u5f55
SELECT *
FROM borrow
WHERE actualdate IS NULL;
8.\u6309\u5e93\u5b58\u6570\u91cf\u964d\u5e8f\u67e5\u8be2\u56fe\u4e66
SELECT bno,bname,stock
FROM book
ORDER BY stock DESC;
9.\u67e5\u8be2\u5e93\u5b58\u6700\u591a\u7684\u524d2\u672c\u56fe\u4e66
SELECT bno,bname,stock
FROM book
ORDER BY stock DESC
LIMIT 2;
10.\u67e5\u8be2\u6240\u6709\u4e0d\u540c\u7684\u51fa\u7248\u793e
SELECT DISTINCT press
FROM book;<\/pre>\n\n\n\n6.\u6570\u636e\u66f4\u65b0\uff08update\/delete\uff09<\/h2>\n\n\n\n 1.\u5c06BOO1\u7684\u5e93\u5b58\u4fee\u6539\u4e3a6
UPDATE book
SET stock = 6
WHERE bno = 'B001';
\u200b
SELECT * FROM book WHERE bno='B001';
2.\u4fee\u6539\u5f20\u660e\u7684\u9662\u7cfb\u548c\u7535\u8bdd
UPDATE reader
SET dept = '\u4eba\u5de5\u667a\u80fd\u5b66\u9662',
phone = '18888888888'
WHERE rno = 'R2024001';
\u200b
SELECT * FROM reader WHERE rno='R2024001';
3.\u5c062018\u5e74\u51fa\u7248\u56fe\u4e66\u5e93\u5b58\u7edf\u4e00\u589e\u52a01
UPDATE book
SET stock = stock + 1
WHERE pubyear = 2018;
\u200b
SELECT * FROM book WHERE pubyear=2018;
4.\u5220\u9664\u4e00\u4e2a\u6d4b\u8bd5\u8bfb\u8005
INSERT INTO reader
VALUES('R2024999','\u6d4b\u8bd5\u8bfb\u8005','\u7537','\u6d4b\u8bd5\u5b66\u9662','\u65e0');
\u200b
DELETE FROM reader
WHERE rno = 'R2024999';
5.\u4e8b\u52a1\u63a7\u5236\uff1a\u66f4\u65b0\u540e\u56de\u6eda
START TRANSACTION;
\u200b
UPDATE book
SET stock = stock - 1
WHERE bno = 'B003';
\u200b
SELECT * FROM book WHERE bno='B003';
\u200b
ROLLBACK;
\u200b
SELECT * FROM book WHERE bno='B003';<\/pre>\n\n\n\n7.\u805a\u5408\u67e5\u8be2\u4e0e\u5206\u7ec4\u7edf\u8ba1<\/h2>\n\n\n\n 1.\u7edf\u8ba1\u56fe\u4e66\u603b\u6570
select count(*) as \u56fe\u4e66\u603b\u6570 from book;
2.\u7edf\u8ba1\u56fe\u4e66\u5e93\u5b58\u603b\u91cf
select sum(stock) as \u5e93\u5b58\u603b\u91cf from book;
3.\u7edf\u8ba1\u5e73\u5747\u5e93\u5b58
select avg(stock) as \u5e73\u5747\u5e93\u5b58 from book;
4.\u67e5\u8be2\u6700\u5927\u5e93\u5b58\u548c\u6700\u5c0f\u5e93\u5b58
SELECT MAX(stock) AS \u6700\u5927\u5e93\u5b58,
MIN(stock) AS \u6700\u5c0f\u5e93\u5b58
FROM book;
5.\u6309\u51fa\u7248\u793e\u7edf\u8ba1\u56fe\u4e66\u6570\u91cf\uff0c\u5e76\u7b5b\u9009\u6570\u91cf\u5927\u4e8e\u7b49\u4e8e1\u7684\u51fa\u7248\u793e
SELECT press, COUNT(*) AS \u56fe\u4e66\u6570\u91cf
FROM book
GROUP BY press
HAVING COUNT(*) >= 1;<\/pre>\n\n\n\n8.\u591a\u8868\u8fde\u63a5\u67e5\u8be2<\/h2>\n\n\n\n1.\u7b49\u503c\u8fde\u63a5\uff1a\u67e5\u8be2\u8bfb\u8005\u59d3\u540d\u548c\u6240\u501f\u56fe\u4e66
SELECT reader.rname, book.bname
FROM reader, borrow, book
WHERE reader.rno = borrow.rno
AND borrow.bno = book.bno;
2.\u5185\u8fde\u63a5\uff1a\u67e5\u8be2\u501f\u9605\u8bb0\u5f55\u8be6\u60c5
SELECT r.rname, b.bname, br.borrowdate, br.returndate
FROM borrow br
JOIN reader r ON br.rno = r.rno
JOIN book b ON br.bno = b.bno;
3.\u5de6\u5916\u8fde\u63a5\uff1a\u67e5\u8be2\u6240\u6709\u8bfb\u8005\u53ca\u5176\u501f\u9605\u8bb0\u5f55
SELECT r.rno, r.rname, br.borrowid, br.bno
FROM reader r
LEFT JOIN borrow br
ON r.rno = br.rno;
4.\u53f3\u5916\u8fde\u63a5\uff1a\u67e5\u8be2\u6240\u6709\u501f\u9605\u8bb0\u5f55\u53ca\u8bfb\u8005\u4fe1\u606f
SELECT r.rname, br.borrowid, br.bno
FROM reader r
RIGHT JOIN borrow br
ON r.rno = br.rno;
5.\u81ea\u8eab\u8fde\u63a5\uff1a\u67e5\u8be2\u540c\u4e00\u5e74\u51fa\u7248\u7684\u4e0d\u540c\u56fe\u4e66
SELECT a.bname AS \u56fe\u4e661,
b.bname AS \u56fe\u4e662,
a.pubyear AS \u51fa\u7248\u5e74\u4efd
FROM book a
JOIN book b
ON a.pubyear = b.pubyear
AND a.bno < b.bno;<\/pre>\n\n\n\n9.\u5d4c\u5957\u67e5\u8be2<\/h2>\n\n\n\n1.IN\uff1a\u67e5\u8be2\u501f\u8fc7\u4e66\u7684\u8bfb\u8005
SELECT *
FROM reader
WHERE rno IN(
SELECT rno FROM borrow
);
2.\u6bd4\u8f83\u8fd0\u7b97\u7b26\uff1a\u67e5\u8be2\u5e93\u5b58\u5927\u4e8e\u5e73\u5747\u5e93\u5b58\u7684\u56fe\u4e66
SELECT bno,bname,stock
FROM book
WHERE stock > (
SELECT AVG(stock)
FROM book
);
3.EXISTS\uff1a\u67e5\u8be2\u5b58\u5728\u501f\u9605\u8bb0\u5f55\u7684\u8bfb\u8005
SELECT *
FROM reader r
WHERE EXISTS(
SELECT *
FROM borrow br
WHERE br.rno = r.rno
);
4.ANY\uff1a\u67e5\u8be2\u5e93\u5b58\u5927\u4e8e\u4efb\u610f\u4e00\u672c2018\u5e74\u51fa\u7248\u56fe\u4e66\u5e93\u5b58\u7684\u56fe\u4e66
SELECT bno,bname,stock
FROM book
WHERE stock > ANY(
SELECT stock
FROM book
WHERE pubyear = 2018
);
5.ALL\uff1a\u67e5\u8be2\u5e93\u5b58\u4e0d\u5c11\u4e8e\u6240\u6709\u56fe\u4e66\u5e93\u5b58\u7684\u56fe\u4e66
SELECT bno,bname,stock
FROM book
WHERE stock >= ALL(
SELECT stock
FROM book
);<\/pre>\n\n\n\n10.\u96c6\u5408\u67e5\u8be2<\/h2>\n\n\n\n1.UNION\uff1a\u5408\u5e76\u8bfb\u8005\u59d3\u540d\u548c\u4f5c\u8005\u59d3\u540d\u5e76\u53bb\u91cd
SELECT rname AS name
FROM reader
UNION
SELECT author AS name
FROM book;
2.UNION ALL\uff1a\u5408\u5e76\u8bfb\u8005\u59d3\u540d\u548c\u4f5c\u8005\u59d3\u540d\uff0c\u4e0d\u53bb\u91cd
SELECT rname AS name
FROM reader
UNION ALL
SELECT author AS name
FROM book;
3.\u6a21\u62df INTERSECT\uff1a\u67e5\u8be2\u501f\u8fc7\u4e66\u7684\u8bfb\u8005\u8bc1\u53f7
SELECT rno
FROM reader
WHERE rno IN(
SELECT rno
FROM borrow
);
4.\u6a21\u62df EXCEPT\uff1a\u67e5\u8be2\u6ca1\u6709\u501f\u4e66\u7684\u8bfb\u8005
SELECT rno,rname
FROM reader
WHERE rno NOT IN(
SELECT rno
FROM borrow
);<\/pre>\n\n\n\n11.\u89c6\u56fe\u64cd\u4f5c<\/h2>\n\n\n\n1.\u521b\u5efa\u672a\u5f52\u8fd8\u56fe\u4e66\u89c6\u56fe
CREATE VIEW v_unreturned AS
SELECT br.borrowid, r.rname, b.bname,
br.borrowdate, br.returndate
FROM borrow br
JOIN reader r ON br.rno = r.rno
JOIN book b ON br.bno = b.bno
WHERE br.actualdate IS NULL;
2.\u67e5\u8be2\u89c6\u56fe
SELECT * FROM v_unreturned;
3.\u521b\u5efa\u5b66\u751f\u8bfb\u8005\u89c6\u56fe\uff0c\u5e26 WITH CHECK OPTION
CREATE VIEW v_student_reader AS
SELECT *
FROM reader
WHERE dept LIKE '%\u5b66\u9662%'
WITH CHECK OPTION;
4.\u6d4b\u8bd5\u53ef\u66f4\u65b0\u89c6\u56fe
UPDATE v_student_reader
SET phone = '18800000000'
WHERE rno = 'R2024002';
\u8bf4\u660e\uff1a
\u8be5\u89c6\u56fe\u57fa\u4e8e\u5355\u8868 reader \u521b\u5efa\uff0c\u6ca1\u6709\u805a\u5408\u51fd\u6570\u3001\u5206\u7ec4\u548c\u8fde\u63a5\uff0c\u56e0\u6b64\u5c5e\u4e8e\u53ef\u66f4\u65b0\u89c6\u56fe\u3002
5.\u521b\u5efa\u4e0d\u53ef\u66f4\u65b0\u7684\u805a\u5408\u89c6\u56fe
CREATE VIEW v_press_count AS
SELECT press, COUNT(*) AS total
FROM book
GROUP BY press;
\u8bf4\u660e\uff1a
\u8be5\u89c6\u56fe\u4f7f\u7528\u4e86 GROUP BY \u548c COUNT \u805a\u5408\u51fd\u6570\uff0c\u56e0\u6b64\u4e00\u822c\u4e0d\u80fd\u76f4\u63a5\u66f4\u65b0\u3002
6.\u5220\u9664\u89c6\u56fe
DROP VIEW v_unreturned;
DROP VIEW v_student_reader;
DROP VIEW v_press_count;<\/pre>\n\n\n\n12.\u7d22\u5f15<\/h2>\n\n\n\n1.\u521b\u5efa\u666e\u901a\u7d22\u5f15
CREATE INDEX idx_book_bname
ON book(bname);
2.\u521b\u5efa\u552f\u4e00\u7d22\u5f15
CREATE UNIQUE INDEX idx_reader_phone
ON reader(phone);
3.\u521b\u5efa\u590d\u5408\u7d22\u5f15
CREATE INDEX idx_borrow_rno_bno
ON borrow(rno,bno);
\u67e5\u770b\u7d22\u5f15
SHOW INDEX FROM book;
SHOW INDEX FROM reader;
SHOW INDEX FROM borrow;
\u5220\u9664\u7d22\u5f15
DROP INDEX idx_book_bname ON book;
DROP INDEX idx_reader_phone ON reader;
DROP INDEX idx_borrow_rno_bno ON borrow;<\/pre>\n\n\n\n13.\u6570\u636e\u5b8c\u6574\u6027\u7ea6\u675f\u9a8c\u8bc1\u4e0e\u7ea7\u8054\u64cd\u4f5c<\/h2>\n\n\n\n1.\u5b9e\u4f53\u5b8c\u6574\u6027\u9a8c\u8bc1\uff1a\u4e3b\u952e\u4e0d\u80fd\u4e3a\u7a7a
INSERT INTO book(bno,bname,author,press,pubyear,stock)
VALUES(NULL,'\u6d4b\u8bd5\u4e66','\u6d4b\u8bd5\u4f5c\u8005','\u6d4b\u8bd5\u51fa\u7248\u793e',2020,1);
\u8bf4\u660e\uff1a
bno \u662f book \u8868\u4e3b\u952e\uff0c\u4e3b\u952e\u4e0d\u80fd\u4e3a\u7a7a\uff0c\u56e0\u6b64\u63d2\u5165\u5931\u8d25\u3002
2.\u53c2\u7167\u5b8c\u6574\u6027\u9a8c\u8bc1\uff1a\u63d2\u5165\u4e0d\u5b58\u5728\u7684\u56fe\u4e66\u7f16\u53f7
INSERT INTO borrow(rno,bno,borrowdate,returndate,actualdate)
VALUES('R2024001','B999','2025-05-01','2025-05-15',NULL);
\u8bf4\u660e\uff1a
B999 \u5728 book \u8868\u4e2d\u4e0d\u5b58\u5728\uff0cborrow.bno \u662f\u5916\u952e\uff0c\u56e0\u6b64\u8fdd\u53cd\u53c2\u7167\u5b8c\u6574\u6027\u3002
3.\u7528\u6237\u5b9a\u4e49\u5b8c\u6574\u6027\u9a8c\u8bc1\uff1a\u5e93\u5b58\u4e0d\u80fd\u5c0f\u4e8e0
UPDATE book
SET stock = -1
WHERE bno = 'B001';
\u8bf4\u660e\uff1a
stock \u5b57\u6bb5\u8bbe\u7f6e\u4e86 CHECK(stock>=0)\uff0c\u5e93\u5b58\u4e0d\u80fd\u4e3a\u8d1f\u6570\u3002
4.\u7528\u6237\u5b9a\u4e49\u5b8c\u6574\u6027\u9a8c\u8bc1\uff1a\u5e93\u5b58\u4e0d\u80fd\u5c0f\u4e8e0
UPDATE book
SET stock = -1
WHERE bno = 'B001';
\u8bf4\u660e\uff1a
stock \u5b57\u6bb5\u8bbe\u7f6e\u4e86 CHECK(stock>=0)\uff0c\u5e93\u5b58\u4e0d\u80fd\u4e3a\u8d1f\u6570\u3002
5.ON UPDATE CASCADE \u6d4b\u8bd5
UPDATE reader
SET rno = 'R2024999'
WHERE rno = 'R2024003';
SELECT * FROM borrow
WHERE rno = 'R2024999';
\u8bf4\u660e\uff1a
reader.rno \u66f4\u65b0\u540e\uff0cborrow \u8868\u4e2d\u5bf9\u5e94\u7684\u5916\u952e rno \u4f1a\u81ea\u52a8\u540c\u6b65\u66f4\u65b0\u3002<\/pre>\n\n\n\n14.\u89e6\u53d1\u5668<\/h2>\n\n\n\n\u51c6\u5907\uff1a\u5220\u9664\u65e7\u89e6\u53d1\u5668
DROP TRIGGER IF EXISTS trg_borrow_before_insert;
DROP TRIGGER IF EXISTS trg_return_after_update;
DROP TRIGGER IF EXISTS trg_reader_before_delete;
\u521b\u5efa\u5220\u9664\u8bfb\u8005\u65e5\u5fd7\u8868
CREATE TABLE reader_delete_log(
logid INT AUTO_INCREMENT PRIMARY KEY,
rno CHAR(12),
rname VARCHAR(20),
dept VARCHAR(40),
delete_time DATETIME DEFAULT CURRENT_TIMESTAMP
);
1.\u501f\u4e66\u65f6\u81ea\u52a8\u51cf\u5c11\u5e93\u5b58
DELIMITER \/\/
CREATE TRIGGER trg_borrow_before_insert
BEFORE INSERT ON borrow
FOR EACH ROW
BEGIN
DECLARE v_stock INT;
SELECT stock INTO v_stock
FROM book
WHERE bno = NEW.bno;
IF v_stock <= 0 THEN
SIGNAL SQLSTATE '45000'
SET MESSAGE_TEXT = '\u5e93\u5b58\u4e0d\u8db3\uff0c\u4e0d\u80fd\u501f\u4e66';
ELSE
UPDATE book
SET stock = stock - 1
WHERE bno = NEW.bno;
END IF;
END \/\/
DELIMITER ;
\u6d4b\u8bd5\uff1a
SELECT stock FROM book WHERE bno='B003';
INSERT INTO borrow(rno,bno,borrowdate,returndate,actualdate)
VALUES('R2024002','B003','2025-05-01','2025-05-15',NULL);
SELECT stock FROM book WHERE bno='B003';
2.\u8fd8\u4e66\u65f6\u81ea\u52a8\u589e\u52a0\u5e93\u5b58\u5e76\u8ba1\u7b97\u7f5a\u6b3e
DELIMITER \/\/
CREATE TRIGGER trg_return_after_update
AFTER UPDATE ON borrow
FOR EACH ROW
BEGIN
IF OLD.actualdate IS NULL AND NEW.actualdate IS NOT NULL THEN
UPDATE book
SET stock = stock + 1
WHERE bno = NEW.bno;
UPDATE borrow
SET fine =
CASE
WHEN NEW.actualdate > NEW.returndate
THEN DATEDIFF(NEW.actualdate, NEW.returndate) * 1
ELSE 0
END
WHERE borrowid = NEW.borrowid;
END IF;
END \/\/
DELIMITER ;
\u6d4b\u8bd5\uff1a
UPDATE borrow
SET actualdate = '2025-05-18'
WHERE rno='R2024002'
AND bno='B003'
AND borrowdate='2025-05-01';
SELECT * FROM borrow
WHERE rno='R2024002'
AND bno='B003';
SELECT stock FROM book WHERE bno='B003';
3.\u5220\u9664\u8bfb\u8005\u524d\u8bb0\u5f55\u65e5\u5fd7
DELIMITER \/\/
CREATE TRIGGER trg_reader_before_delete
BEFORE DELETE ON reader
FOR EACH ROW
BEGIN
INSERT INTO reader_delete_log(rno,rname,dept)
VALUES(OLD.rno, OLD.rname, OLD.dept);
END \/\/
DELIMITER ;
\u6d4b\u8bd5\uff1a
INSERT INTO reader
VALUES('R2024888','\u65e5\u5fd7\u6d4b\u8bd5','\u7537','\u6d4b\u8bd5\u5b66\u9662','\u65e0');
DELETE FROM reader
WHERE rno='R2024888';
SELECT * FROM reader_delete_log;<\/pre>\n\n\n\n15.\u6570\u636e\u5b89\u5168\u6027<\/h2>\n\n\n\n1.\u521b\u5efa\u7528\u6237\u5e76\u6388\u4e88\u67e5\u8be2\u6743\u9650
CREATE USER 'lib_user1'@'localhost'
IDENTIFIED BY '123456';
GRANT SELECT
ON library_db.book
TO 'lib_user1'@'localhost';
\u67e5\u770b\u6743\u9650\uff1a
SHOW GRANTS FOR 'lib_user1'@'localhost';
2.\u6388\u4e88\u6743\u9650\u5e76\u5141\u8bb8\u8f6c\u6388\u6743
GRANT SELECT, INSERT
ON library_db.reader
TO 'lib_user1'@'localhost'
WITH GRANT OPTION;
\u8bf4\u660e\uff1a
WITH GRANT OPTION \u8868\u793a\u8be5\u7528\u6237\u53ef\u4ee5\u5c06\u81ea\u5df1\u62e5\u6709\u7684\u6743\u9650\u518d\u6388\u4e88\u5176\u4ed6\u7528\u6237\u3002
3.\u56de\u6536\u6743\u9650
REVOKE INSERT
ON library_db.reader
FROM 'lib_user1'@'localhost';
4.\u521b\u5efa\u89d2\u8272\u5e76\u6388\u6743
CREATE ROLE 'reader_role';
GRANT SELECT
ON library_db.*
TO 'reader_role';
CREATE USER 'lib_user2'@'localhost'
IDENTIFIED BY '123456';
GRANT 'reader_role'
TO 'lib_user2'@'localhost';
SET DEFAULT ROLE 'reader_role'
TO 'lib_user2'@'localhost';<\/pre>\n\n\n\n16.\u89c6\u56fe\u4e0e\u6d3e\u751f\u8868<\/h2>\n\n\n\n1.\u5e26\u805a\u5408\u51fd\u6570\u7684\u89c6\u56fe\uff1a\u7edf\u8ba1\u6bcf\u4e2a\u8bfb\u8005\u501f\u9605\u6b21\u6570
CREATE VIEW v_reader_borrow_count AS
SELECT r.rno, r.rname, COUNT(br.borrowid) AS borrow_count
FROM reader r
LEFT JOIN borrow br
ON r.rno = br.rno
GROUP BY r.rno, r.rname;
\u67e5\u8be2\uff1a
SELECT * FROM v_reader_borrow_count;
2.\u6d3e\u751f\u8868\uff1a\u67e5\u8be2\u501f\u9605\u6b21\u6570\u5927\u4e8e1\u7684\u8bfb\u8005
SELECT *
FROM (
SELECT rno, COUNT(*) AS borrow_count
FROM borrow
GROUP BY rno
) AS t
WHERE t.borrow_count > 1;
3.WITH \u5b50\u53e5\u7edf\u8ba1\u6bcf\u4f4d\u8bfb\u8005\u501f\u9605\u6570\u91cf
WITH reader_count AS (
SELECT rno, COUNT(*) AS total
FROM borrow
GROUP BY rno
)
SELECT r.rno, r.rname, rc.total
FROM reader r
LEFT JOIN reader_count rc
ON r.rno = rc.rno;
4.WITH \u5b50\u53e5\uff1a\u67e5\u8be2\u672a\u5f52\u8fd8\u56fe\u4e66
WITH unreturned AS (
SELECT br.borrowid, r.rname, b.bname,
br.borrowdate, br.returndate
FROM borrow br
JOIN reader r ON br.rno = r.rno
JOIN book b ON br.bno = b.bno
WHERE br.actualdate IS NULL
)
SELECT * FROM unreturned;<\/pre>\n\n\n\n17.\u6269\u5c55\u601d\u8003<\/h2>\n\n\n\n\n- \u5982\u4f55\u5904\u7406\u5206\u7c7b\u5b9e\u4f53\u7684\u81ea\u5173\u8054\uff1f<\/li>\n<\/ol>\n\n\n\n
\u5206\u7c7b\u5b9e\u4f53\u5b58\u5728\u201c\u4e0a\u7ea7\u5206\u7c7b\u201d\u548c\u201c\u4e0b\u7ea7\u5206\u7c7b\u201d\u7684\u5173\u7cfb\uff0c\u56e0\u6b64\u53ef\u4ee5\u5728 category \u8868\u4e2d\u8bbe\u7f6e parentid \u5b57\u6bb5\u3002
category(
cid,
cname,
parentid
)
\u5176\u4e2d cid \u662f\u5206\u7c7b\u7f16\u53f7\uff0cparentid \u662f\u4e0a\u7ea7\u5206\u7c7b\u7f16\u53f7\uff0c\u540c\u65f6 parentid \u4e5f\u662f\u6307\u5411 category.cid \u7684\u5916\u952e\u3002
\u5982\u679c\u67d0\u5206\u7c7b\u6ca1\u6709\u4e0a\u7ea7\u5206\u7c7b\uff0c\u5219 parentid \u53ef\u4ee5\u4e3a\u7a7a\u3002
\u8fd9\u79cd\u8bbe\u8ba1\u53ef\u4ee5\u8868\u793a\u6811\u5f62\u7ed3\u6784\uff0c\u4f8b\u5982\uff1a
\u56fe\u4e66
\u251c\u2500\u2500 \u8ba1\u7b97\u673a
\u2502 \u251c\u2500\u2500 \u6570\u636e\u5e93
\u2502 \u2514\u2500\u2500 \u7f51\u7edc\u6280\u672f
\u2514\u2500\u2500 \u6587\u5b66
\u2514\u2500\u2500 \u79d1\u5e7b\u5c0f\u8bf4<\/pre>\n\n\n\n
\n\n\n\n2. \u501f\u9605\u5173\u7cfb\u662f\u5426\u53ef\u80fd\u5b58\u5728\u6570\u636e\u5197\u4f59\uff1f<\/h2>\n\n\n\n\u501f\u9605\u8868\u5982\u679c\u53ea\u4fdd\u5b58 rno\u3001bno\u3001borrowdate\u3001returndate\u3001actualdate \u7b49\u4fe1\u606f\uff0c\u5219\u5197\u4f59\u8f83\u5c11\u3002
\u4f46\u662f\u5982\u679c\u5728 borrow \u8868\u4e2d\u540c\u65f6\u4fdd\u5b58\u8bfb\u8005\u59d3\u540d rname\u3001\u56fe\u4e66\u540d\u79f0 bname\u3001\u51fa\u7248\u793e press \u7b49\u4fe1\u606f\uff0c\u5c31\u4f1a\u4ea7\u751f\u6570\u636e\u5197\u4f59\u3002
\u4f8b\u5982\uff1a
borrow(borrowid, rno, rname, bno, bname, borrowdate)
\u5176\u4e2d rname \u4f9d\u8d56 rno\uff0cbname \u4f9d\u8d56 bno\uff0c\u800c\u4e0d\u662f\u76f4\u63a5\u4f9d\u8d56 borrowid\uff0c\u4f1a\u4ea7\u751f\u4f20\u9012\u4f9d\u8d56\u3002
\u89c4\u8303\u5316\u65b9\u6848\uff1a
\u5c06\u8bfb\u8005\u4fe1\u606f\u4fdd\u5b58\u5728 reader \u8868\uff1b
\u5c06\u56fe\u4e66\u4fe1\u606f\u4fdd\u5b58\u5728 book \u8868\uff1b
borrow \u8868\u53ea\u4fdd\u5b58\u8bfb\u8005\u8bc1\u53f7\u548c\u56fe\u4e66\u7f16\u53f7\u4f5c\u4e3a\u5916\u952e\u3002<\/pre>\n\n\n\n
\n\n\n\n3. \u5982\u4f55\u9632\u6b62\u5e93\u5b58\u4e3a\u8d1f\u6570\uff1f<\/h2>\n\n\n\n\u53ef\u4ee5\u4ece\u4e24\u4e2a\u65b9\u9762\u9632\u6b62\u5e93\u5b58\u4e3a\u8d1f\u6570\uff1a
\u7b2c\u4e00\uff0c\u5728 book \u8868\u4e2d\u8bbe\u7f6e CHECK(stock >= 0) \u7ea6\u675f\uff0c\u4fdd\u8bc1\u5e93\u5b58\u4e0d\u80fd\u5c0f\u4e8e0\u3002
\u7b2c\u4e8c\uff0c\u5728\u501f\u4e66\u89e6\u53d1\u5668\u4e2d\u5224\u65ad\u5e93\u5b58\u6570\u91cf\u3002
\u5f53\u63d2\u5165 borrow \u501f\u9605\u8bb0\u5f55\u65f6\uff0c\u5148\u67e5\u8be2\u56fe\u4e66\u5e93\u5b58\u3002
\u5982\u679c\u5e93\u5b58\u5c0f\u4e8e\u7b49\u4e8e0\uff0c\u5219\u4f7f\u7528 SIGNAL \u629b\u51fa\u9519\u8bef\uff0c\u963b\u6b62\u501f\u4e66\u64cd\u4f5c\uff1b
\u5982\u679c\u5e93\u5b58\u5927\u4e8e0\uff0c\u5219\u5141\u8bb8\u501f\u9605\uff0c\u5e76\u81ea\u52a8\u5c06\u5e93\u5b58\u51cf1\u3002
\u8fd9\u6837\u53ef\u4ee5\u4fdd\u8bc1\u501f\u4e66\u65f6\u4e0d\u4f1a\u51fa\u73b0\u5e93\u5b58\u4e3a\u8d1f\u6570\u7684\u60c5\u51b5\u3002<\/pre>\n\n\n\n
\n\n\n\n4. \u9884\u7ea6\u56fe\u4e66\u529f\u80fd\u9700\u8981\u589e\u52a0\u54ea\u4e9b\u5b9e\u4f53\u548c\u5173\u7cfb\uff1f<\/h2>\n\n\n\n\u5982\u679c\u7cfb\u7edf\u652f\u6301\u9884\u7ea6\u56fe\u4e66\u529f\u80fd\uff0c\u53ef\u4ee5\u589e\u52a0 reservation \u9884\u7ea6\u8868\u3002
reservation(
reserveid,
rno,
bno,
reservedate,
status
)
\u5176\u4e2d\uff1a
reserveid \u8868\u793a\u9884\u7ea6\u7f16\u53f7\uff1b
rno \u662f\u8bfb\u8005\u8bc1\u53f7\uff0c\u5916\u952e\u5f15\u7528 reader.rno\uff1b
bno \u662f\u56fe\u4e66\u7f16\u53f7\uff0c\u5916\u952e\u5f15\u7528 book.bno\uff1b
reservedate \u8868\u793a\u9884\u7ea6\u65e5\u671f\uff1b
status \u8868\u793a\u9884\u7ea6\u72b6\u6001\uff0c\u5982\u201c\u9884\u7ea6\u4e2d\u201d\u201c\u5df2\u53d6\u6d88\u201d\u201c\u5df2\u5b8c\u6210\u201d\u3002
\u65b0\u589e\u5173\u7cfb\uff1a
\u4e00\u4e2a\u8bfb\u8005\u53ef\u4ee5\u9884\u7ea6\u591a\u672c\u56fe\u4e66\uff1b
\u4e00\u672c\u56fe\u4e66\u53ef\u4ee5\u88ab\u591a\u4e2a\u8bfb\u8005\u9884\u7ea6\uff1b
\u8bfb\u8005\u548c\u56fe\u4e66\u4e4b\u95f4\u901a\u8fc7 reservation \u8868\u5f62\u6210 m:n \u8054\u7cfb\u3002<\/pre>\n\n\n\n
\n\n\n\n5. \u4e3a\u4ec0\u4e48\u9075\u5faa\u6700\u5c0f\u6743\u9650\u539f\u5219\uff1f<\/h2>\n\n\n\n\u6700\u5c0f\u6743\u9650\u539f\u5219\u662f\u6307\u53ea\u7ed9\u7528\u6237\u5b8c\u6210\u5de5\u4f5c\u6240\u5fc5\u9700\u7684\u6743\u9650\uff0c\u4e0d\u6388\u4e88\u591a\u4f59\u6743\u9650\u3002
\u5728\u672c\u5b9e\u9a8c\u4e2d\uff0c\u5982\u679c\u67d0\u7528\u6237\u53ea\u8d1f\u8d23\u67e5\u8be2\u56fe\u4e66\u4fe1\u606f\uff0c\u5219\u53ea\u6388\u4e88 SELECT \u6743\u9650\u5373\u53ef\uff0c\u4e0d\u5e94\u8be5\u6388\u4e88 INSERT\u3001UPDATE\u3001DELETE \u7b49\u6743\u9650\u3002
\u4f8b\u5982\uff1a
GRANT SELECT ON library_db.book TO 'lib_user1'@'localhost';
\u8fd9\u6837\u53ef\u4ee5\u9632\u6b62\u7528\u6237\u8bef\u5220\u3001\u8bef\u6539\u6570\u636e\uff0c\u63d0\u9ad8\u6570\u636e\u5e93\u5b89\u5168\u6027\u3002
\u5982\u679c\u540e\u7eed\u4e0d\u518d\u9700\u8981\u67d0\u9879\u6743\u9650\uff0c\u8fd8\u53ef\u4ee5\u4f7f\u7528 REVOKE \u56de\u6536\u6743\u9650\u3002<\/pre>\n\n\n\n
\n\n\n\n6. \u5e76\u53d1\u501f\u9605\u5e93\u5b58\u4ec5\u52691\u672c\u7684\u56fe\u4e66\u4f1a\u4ea7\u751f\u4ec0\u4e48\u95ee\u9898\uff1f\u5982\u4f55\u89e3\u51b3\uff1f<\/h2>\n\n\n\n\u5f53\u591a\u7528\u6237\u540c\u65f6\u501f\u9605\u540c\u4e00\u672c\u5e93\u5b58\u4ec5\u52691\u672c\u7684\u56fe\u4e66\u65f6\uff0c\u53ef\u80fd\u51fa\u73b0\u8d85\u5356\u95ee\u9898\u3002
\u4f8b\u5982\u4e24\u4e2a\u7528\u6237\u540c\u65f6\u8bfb\u53d6\u5e93\u5b58 stock=1\uff0c\u90fd\u8ba4\u4e3a\u53ef\u4ee5\u501f\u9605\uff0c\u7136\u540e\u540c\u65f6\u63d2\u5165\u501f\u9605\u8bb0\u5f55\u5e76\u6267\u884c\u5e93\u5b58\u51cf1\uff0c\u6700\u7ec8\u53ef\u80fd\u5bfc\u81f4\u5e93\u5b58\u5f02\u5e38\u6216\u51fa\u73b0\u8d85\u989d\u501f\u9605\u3002
\u89e3\u51b3\u65b9\u6cd5\uff1a
1. \u4f7f\u7528\u4e8b\u52a1\u4fdd\u8bc1\u501f\u4e66\u64cd\u4f5c\u7684\u539f\u5b50\u6027\uff1b
2. \u4f7f\u7528 SELECT ... FOR UPDATE \u5bf9\u56fe\u4e66\u5e93\u5b58\u8bb0\u5f55\u52a0\u884c\u7ea7\u9501\uff1b
3. \u5728\u89e6\u53d1\u5668\u4e2d\u5224\u65ad\u5e93\u5b58\u662f\u5426\u5927\u4e8e0\uff1b
4. \u7ed9 stock \u5b57\u6bb5\u8bbe\u7f6e CHECK(stock >= 0) \u7ea6\u675f\u3002
\u793a\u4f8b\uff1a
START TRANSACTION;
SELECT stock
FROM book
WHERE bno='B001'
FOR UPDATE;
UPDATE book
SET stock = stock - 1
WHERE bno='B001'
AND stock > 0;
INSERT INTO borrow(rno,bno,borrowdate,returndate)
VALUES('R2024001','B001','2025-05-01','2025-05-15');
COMMIT;
\u8fd9\u6837\u53ef\u4ee5\u907f\u514d\u591a\u4e2a\u7528\u6237\u540c\u65f6\u4fee\u6539\u5e93\u5b58\u5bfc\u81f4\u6570\u636e\u4e0d\u4e00\u81f4\u3002<\/pre>\n\n\n\n
\n\n\n\n\u5b9e\u9a8c\u603b\u7ed3<\/h1>\n\n\n\n \u901a\u8fc7\u672c\u6b21\u56fe\u4e66\u501f\u9605\u7ba1\u7406\u7cfb\u7edf\u7efc\u5408\u5b9e\u9a8c\uff0c\u6211\u7cfb\u7edf\u5730\u5b8c\u6210\u4e86\u6570\u636e\u5e93\u8bbe\u8ba1\u4e0e\u5b9e\u73b0\u7684\u5168\u8fc7\u7a0b\u3002\u5b9e\u9a8c\u4ece\u9700\u6c42\u5206\u6790\u5f00\u59cb\uff0c\u9010\u6b65\u5b8c\u6210 E-R \u56fe\u8bbe\u8ba1\u3001\u5173\u7cfb\u6a21\u5f0f\u8f6c\u6362\u3001\u7269\u7406\u8868\u7ed3\u6784\u8bbe\u8ba1\u3001\u6570\u636e\u63d2\u5165\u3001\u67e5\u8be2\u64cd\u4f5c\u3001\u89c6\u56fe\u3001\u7d22\u5f15\u3001\u5b8c\u6574\u6027\u7ea6\u675f\u3001\u89e6\u53d1\u5668\u548c\u6743\u9650\u7ba1\u7406\u7b49\u5185\u5bb9\uff0c\u4f7f\u6211\u5bf9\u6570\u636e\u5e93\u5e94\u7528\u7cfb\u7edf\u7684\u8bbe\u8ba1\u6d41\u7a0b\u6709\u4e86\u66f4\u52a0\u5b8c\u6574\u7684\u8ba4\u8bc6\u3002
\u200b
\u5728\u5b9e\u9a8c\u8fc7\u7a0b\u4e2d\uff0c\u6211\u9996\u5148\u6839\u636e\u56fe\u4e66\u9986\u4e1a\u52a1\u9700\u6c42\u5206\u6790\u51fa\u56fe\u4e66\u3001\u8bfb\u8005\u3001\u501f\u9605\u3001\u51fa\u7248\u793e\u3001\u5206\u7c7b\u7b49\u5b9e\u4f53\uff0c\u5e76\u660e\u786e\u4e86\u5b83\u4eec\u4e4b\u95f4\u7684\u8054\u7cfb\u7c7b\u578b\u3002\u4f8b\u5982\uff0c\u51fa\u7248\u793e\u4e0e\u56fe\u4e66\u4e4b\u95f4\u662f\u4e00\u5bf9\u591a\u5173\u7cfb\uff0c\u5206\u7c7b\u4e0e\u56fe\u4e66\u4e4b\u95f4\u662f\u4e00\u5bf9\u591a\u5173\u7cfb\uff0c\u8bfb\u8005\u4e0e\u56fe\u4e66\u4e4b\u95f4\u901a\u8fc7\u501f\u9605\u8868\u5f62\u6210\u591a\u5bf9\u591a\u5173\u7cfb\u3002\u901a\u8fc7 E-R \u56fe\u8bbe\u8ba1\uff0c\u6211\u8fdb\u4e00\u6b65\u7406\u89e3\u4e86\u6982\u5ff5\u7ed3\u6784\u8bbe\u8ba1\u5728\u6570\u636e\u5e93\u5f00\u53d1\u4e2d\u7684\u91cd\u8981\u4f5c\u7528\u3002
\u200b
\u5728\u903b\u8f91\u7ed3\u6784\u8bbe\u8ba1\u9636\u6bb5\uff0c\u6211\u5c06 E-R \u56fe\u8f6c\u6362\u4e3a\u5173\u7cfb\u6a21\u5f0f\uff0c\u5e76\u5206\u6790\u5404\u8868\u662f\u5426\u6ee1\u8db3\u7b2c\u4e09\u8303\u5f0f\u3002\u901a\u8fc7\u89c4\u8303\u5316\u8bbe\u8ba1\uff0c\u907f\u514d\u4e86\u5728\u501f\u9605\u8868\u4e2d\u91cd\u590d\u4fdd\u5b58\u8bfb\u8005\u59d3\u540d\u3001\u56fe\u4e66\u540d\u79f0\u7b49\u4fe1\u606f\uff0c\u51cf\u5c11\u4e86\u6570\u636e\u5197\u4f59\uff0c\u63d0\u9ad8\u4e86\u6570\u636e\u4e00\u81f4\u6027\u3002\u5728\u7269\u7406\u8bbe\u8ba1\u9636\u6bb5\uff0c\u6211\u4f7f\u7528 SQL \u521b\u5efa\u6570\u636e\u5e93\u548c\u6570\u636e\u8868\uff0c\u8bbe\u7f6e\u4e86\u4e3b\u952e\u3001\u5916\u952e\u3001\u975e\u7a7a\u3001\u9ed8\u8ba4\u503c\u548c CHECK \u7ea6\u675f\uff0c\u5bf9\u5b9e\u4f53\u5b8c\u6574\u6027\u3001\u53c2\u7167\u5b8c\u6574\u6027\u548c\u7528\u6237\u5b9a\u4e49\u5b8c\u6574\u6027\u6709\u4e86\u66f4\u6df1\u523b\u7684\u7406\u89e3\u3002
\u200b
\u5728\u6570\u636e\u64cd\u4f5c\u90e8\u5206\uff0c\u6211\u7ec3\u4e60\u4e86 INSERT\u3001UPDATE\u3001DELETE \u548c SELECT \u8bed\u53e5\uff0c\u5e76\u5b8c\u6210\u4e86\u57fa\u7840\u67e5\u8be2\u3001\u805a\u5408\u67e5\u8be2\u3001\u591a\u8868\u8fde\u63a5\u67e5\u8be2\u3001\u5d4c\u5957\u67e5\u8be2\u548c\u96c6\u5408\u67e5\u8be2\u7b49\u5185\u5bb9\u3002\u901a\u8fc7\u8fd9\u4e9b\u7ec3\u4e60\uff0c\u6211\u638c\u63e1\u4e86 SQL \u67e5\u8be2\u8bed\u53e5\u7684\u5e38\u89c1\u5199\u6cd5\uff0c\u5c24\u5176\u662f\u591a\u8868\u8fde\u63a5\u548c\u5d4c\u5957\u67e5\u8be2\u7684\u4f7f\u7528\u65b9\u6cd5\u3002\u5b9e\u9a8c\u4e2d\u8fd8\u521b\u5efa\u4e86\u89c6\u56fe\u548c\u7d22\u5f15\uff0c\u7406\u89e3\u4e86\u89c6\u56fe\u53ef\u4ee5\u7b80\u5316\u590d\u6742\u67e5\u8be2\uff0c\u7d22\u5f15\u53ef\u4ee5\u63d0\u9ad8\u67e5\u8be2\u6548\u7387\uff0c\u4f46\u4e5f\u4f1a\u589e\u52a0\u7ef4\u62a4\u6210\u672c\u3002
\u200b
\u5728\u89e6\u53d1\u5668\u90e8\u5206\uff0c\u6211\u5b9e\u73b0\u4e86\u501f\u4e66\u81ea\u52a8\u51cf\u5c11\u5e93\u5b58\u3001\u8fd8\u4e66\u81ea\u52a8\u589e\u52a0\u5e93\u5b58\u5e76\u8ba1\u7b97\u7f5a\u6b3e\u3001\u5220\u9664\u8bfb\u8005\u524d\u8bb0\u5f55\u65e5\u5fd7\u7b49\u529f\u80fd\u3002\u901a\u8fc7\u89e6\u53d1\u5668\u5b9e\u9a8c\uff0c\u6211\u8ba4\u8bc6\u5230\u6570\u636e\u5e93\u4e0d\u4ec5\u53ef\u4ee5\u5b58\u50a8\u6570\u636e\uff0c\u8fd8\u53ef\u4ee5\u5728\u7279\u5b9a\u64cd\u4f5c\u53d1\u751f\u65f6\u81ea\u52a8\u6267\u884c\u4e00\u4e9b\u4e1a\u52a1\u903b\u8f91\u3002\u5b9e\u9a8c\u8fc7\u7a0b\u4e2d\u4e5f\u9047\u5230\u4e86\u4e00\u4e9b\u95ee\u9898\uff0c\u4f8b\u5982\u5916\u952e\u7ea6\u675f\u5bfc\u81f4\u6570\u636e\u65e0\u6cd5\u5220\u9664\u3001CHECK \u7ea6\u675f\u63d2\u5165\u5931\u8d25\u3001\u89e6\u53d1\u5668\u8bed\u6cd5\u9519\u8bef\u7b49\u3002\u901a\u8fc7\u67e5\u770b\u9519\u8bef\u4fe1\u606f\u3001\u4fee\u6539 SQL \u8bed\u53e5\u548c\u53cd\u590d\u6d4b\u8bd5\uff0c\u6700\u7ec8\u89e3\u51b3\u4e86\u8fd9\u4e9b\u95ee\u9898\u3002
\u200b
\u901a\u8fc7\u672c\u6b21\u5b9e\u9a8c\uff0c\u6211\u4e0d\u4ec5\u5de9\u56fa\u4e86\u6570\u636e\u5e93\u7406\u8bba\u77e5\u8bc6\uff0c\u4e5f\u63d0\u9ad8\u4e86 SQL \u7f16\u5199\u80fd\u529b\u548c\u6570\u636e\u5e93\u8c03\u8bd5\u80fd\u529b\u3002\u4eca\u540e\u5728\u8bbe\u8ba1\u6570\u636e\u5e93\u7cfb\u7edf<\/pre>\n","protected":false},"excerpt":{"rendered":"\u6570\u636e\u5e93\u7efc\u5408\u5b9e\u9a8c 1.\u9700\u6c42\u5206\u6790 \u67d0\u5927\u578b\u56fe\u4e66\u9986\u9700\u8981\u5f00\u53d1\u4e00\u5957\u6570\u5b57\u5316\u501f\u9605\u7ba1\u7406\u7cfb\u7edf\uff0c\u4e3b\u8981\u4e1a\u52a1\u9700\u6c42\u5982\u4e0b\uff1a \u56fe\u4e66\u4fe1\u606f\uff1a\u8bb0\u5f55\u56fe […]<\/p>\n","protected":false},"author":1,"featured_media":448,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[9],"tags":[],"class_list":["post-446","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-wenzhang"],"_links":{"self":[{"href":"https:\/\/fg2025.cn\/index.php\/wp-json\/wp\/v2\/posts\/446","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/fg2025.cn\/index.php\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/fg2025.cn\/index.php\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/fg2025.cn\/index.php\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/fg2025.cn\/index.php\/wp-json\/wp\/v2\/comments?post=446"}],"version-history":[{"count":0,"href":"https:\/\/fg2025.cn\/index.php\/wp-json\/wp\/v2\/posts\/446\/revisions"}],"wp:attachment":[{"href":"https:\/\/fg2025.cn\/index.php\/wp-json\/wp\/v2\/media?parent=446"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/fg2025.cn\/index.php\/wp-json\/wp\/v2\/categories?post=446"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/fg2025.cn\/index.php\/wp-json\/wp\/v2\/tags?post=446"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}
rno,bno,
borrowdate,
returndate)
VALUES(
'R999999',
'B001',
'2025-05-01',
'2025-05-15');
\u200b
\u9519\u8bef\uff1aCannot add or update a child row:
a foreign key constraint fails
\u200b
\u539f\u56e0\uff1aR999999\u5728reader\u8868\u4e2d\u4e0d\u5b58\u5728\uff0c
\u8fdd\u53cd\u53c2\u7167\u5b8c\u6574\u6027\u7ea6\u675f\u3002
\u200b
\u8fdd\u53cdcheck
INSERT INTO reader
VALUES(
'R2024004',
'\u8d75\u654f',
'\u672a\u77e5',
'\u827a\u672f\u5b66\u9662',
'13712345678');
\u200b
\u9519\u8bef\uff1aCheck constraint violated
\u200b
\u539f\u56e0\uff1arsex\u5b57\u6bb5\u53ea\u80fd\u53d6
\u7537 \u6216 \u5973\uff0c
\u56e0\u6b64\u8fdd\u53cdCHECK\u7ea6\u675f\u3002<\/pre>\n\n\n\n
5.\u6570\u636e\u67e5\u8be2\uff08DQL-\u57fa\u7840\u67e5\u8be2\uff09<\/h2>\n\n\n\n 1.select\u67e5\u8be2\u5168\u90e8\u56fe\u4e66\u4fe1\u606f
select * from book;
2.\u67e5\u8be2\u5e93\u5b58\u5927\u4e8e3\u7684\u56fe\u4e66
SELECT bno,bname,stock
FROM book
WHERE stock > 3;
3.\u67e5\u8be22018\u5e74\u51fa\u7248\u4e14\u5e93\u5b58\u4e0d\u5c11\u4e8e4\u672c\u7684\u56fe\u4e66
SELECT bno,bname,pubyear,stock
FROM book
WHERE pubyear = 2018 AND stock >= 4;
4.\u67e5\u8be22015\u5e74\u81f32018\u5e74\u51fa\u7248\u7684\u56fe\u4e66
SELECT bno,bname,pubyear
FROM book
WHERE pubyear BETWEEN 2015 AND 2018;
5.\u67e5\u8be2\u51fa\u7248\u793e\u4e3a\u201c\u91cd\u5e86\u51fa\u7248\u793e\u201d\u6216\u201c\u9ad8\u7b49\u6559\u80b2\u51fa\u7248\u793e\u201d\u7684\u56fe\u4e66
SELECT bno,bname,press
FROM book
WHERE press IN('\u91cd\u5e86\u51fa\u7248\u793e','\u9ad8\u7b49\u6559\u80b2\u51fa\u7248\u793e');
6.\u67e5\u8be2\u4e66\u540d\u4e2d\u5305\u542b\u201c\u8ba1\u7b97\u673a\u201d\u7684\u56fe\u4e66
SELECT bno,bname
FROM book
WHERE bname LIKE '%\u8ba1\u7b97\u673a%';
7.\u67e5\u8be2\u5c1a\u672a\u5f52\u8fd8\u7684\u501f\u9605\u8bb0\u5f55
SELECT *
FROM borrow
WHERE actualdate IS NULL;
8.\u6309\u5e93\u5b58\u6570\u91cf\u964d\u5e8f\u67e5\u8be2\u56fe\u4e66
SELECT bno,bname,stock
FROM book
ORDER BY stock DESC;
9.\u67e5\u8be2\u5e93\u5b58\u6700\u591a\u7684\u524d2\u672c\u56fe\u4e66
SELECT bno,bname,stock
FROM book
ORDER BY stock DESC
LIMIT 2;
10.\u67e5\u8be2\u6240\u6709\u4e0d\u540c\u7684\u51fa\u7248\u793e
SELECT DISTINCT press
FROM book;<\/pre>\n\n\n\n6.\u6570\u636e\u66f4\u65b0\uff08update\/delete\uff09<\/h2>\n\n\n\n 1.\u5c06BOO1\u7684\u5e93\u5b58\u4fee\u6539\u4e3a6
UPDATE book
SET stock = 6
WHERE bno = 'B001';
\u200b
SELECT * FROM book WHERE bno='B001';
2.\u4fee\u6539\u5f20\u660e\u7684\u9662\u7cfb\u548c\u7535\u8bdd
UPDATE reader
SET dept = '\u4eba\u5de5\u667a\u80fd\u5b66\u9662',
phone = '18888888888'
WHERE rno = 'R2024001';
\u200b
SELECT * FROM reader WHERE rno='R2024001';
3.\u5c062018\u5e74\u51fa\u7248\u56fe\u4e66\u5e93\u5b58\u7edf\u4e00\u589e\u52a01
UPDATE book
SET stock = stock + 1
WHERE pubyear = 2018;
\u200b
SELECT * FROM book WHERE pubyear=2018;
4.\u5220\u9664\u4e00\u4e2a\u6d4b\u8bd5\u8bfb\u8005
INSERT INTO reader
VALUES('R2024999','\u6d4b\u8bd5\u8bfb\u8005','\u7537','\u6d4b\u8bd5\u5b66\u9662','\u65e0');
\u200b
DELETE FROM reader
WHERE rno = 'R2024999';
5.\u4e8b\u52a1\u63a7\u5236\uff1a\u66f4\u65b0\u540e\u56de\u6eda
START TRANSACTION;
\u200b
UPDATE book
SET stock = stock - 1
WHERE bno = 'B003';
\u200b
SELECT * FROM book WHERE bno='B003';
\u200b
ROLLBACK;
\u200b
SELECT * FROM book WHERE bno='B003';<\/pre>\n\n\n\n7.\u805a\u5408\u67e5\u8be2\u4e0e\u5206\u7ec4\u7edf\u8ba1<\/h2>\n\n\n\n 1.\u7edf\u8ba1\u56fe\u4e66\u603b\u6570
select count(*) as \u56fe\u4e66\u603b\u6570 from book;
2.\u7edf\u8ba1\u56fe\u4e66\u5e93\u5b58\u603b\u91cf
select sum(stock) as \u5e93\u5b58\u603b\u91cf from book;
3.\u7edf\u8ba1\u5e73\u5747\u5e93\u5b58
select avg(stock) as \u5e73\u5747\u5e93\u5b58 from book;
4.\u67e5\u8be2\u6700\u5927\u5e93\u5b58\u548c\u6700\u5c0f\u5e93\u5b58
SELECT MAX(stock) AS \u6700\u5927\u5e93\u5b58,
MIN(stock) AS \u6700\u5c0f\u5e93\u5b58
FROM book;
5.\u6309\u51fa\u7248\u793e\u7edf\u8ba1\u56fe\u4e66\u6570\u91cf\uff0c\u5e76\u7b5b\u9009\u6570\u91cf\u5927\u4e8e\u7b49\u4e8e1\u7684\u51fa\u7248\u793e
SELECT press, COUNT(*) AS \u56fe\u4e66\u6570\u91cf
FROM book
GROUP BY press
HAVING COUNT(*) >= 1;<\/pre>\n\n\n\n8.\u591a\u8868\u8fde\u63a5\u67e5\u8be2<\/h2>\n\n\n\n1.\u7b49\u503c\u8fde\u63a5\uff1a\u67e5\u8be2\u8bfb\u8005\u59d3\u540d\u548c\u6240\u501f\u56fe\u4e66
SELECT reader.rname, book.bname
FROM reader, borrow, book
WHERE reader.rno = borrow.rno
AND borrow.bno = book.bno;
2.\u5185\u8fde\u63a5\uff1a\u67e5\u8be2\u501f\u9605\u8bb0\u5f55\u8be6\u60c5
SELECT r.rname, b.bname, br.borrowdate, br.returndate
FROM borrow br
JOIN reader r ON br.rno = r.rno
JOIN book b ON br.bno = b.bno;
3.\u5de6\u5916\u8fde\u63a5\uff1a\u67e5\u8be2\u6240\u6709\u8bfb\u8005\u53ca\u5176\u501f\u9605\u8bb0\u5f55
SELECT r.rno, r.rname, br.borrowid, br.bno
FROM reader r
LEFT JOIN borrow br
ON r.rno = br.rno;
4.\u53f3\u5916\u8fde\u63a5\uff1a\u67e5\u8be2\u6240\u6709\u501f\u9605\u8bb0\u5f55\u53ca\u8bfb\u8005\u4fe1\u606f
SELECT r.rname, br.borrowid, br.bno
FROM reader r
RIGHT JOIN borrow br
ON r.rno = br.rno;
5.\u81ea\u8eab\u8fde\u63a5\uff1a\u67e5\u8be2\u540c\u4e00\u5e74\u51fa\u7248\u7684\u4e0d\u540c\u56fe\u4e66
SELECT a.bname AS \u56fe\u4e661,
b.bname AS \u56fe\u4e662,
a.pubyear AS \u51fa\u7248\u5e74\u4efd
FROM book a
JOIN book b
ON a.pubyear = b.pubyear
AND a.bno < b.bno;<\/pre>\n\n\n\n9.\u5d4c\u5957\u67e5\u8be2<\/h2>\n\n\n\n1.IN\uff1a\u67e5\u8be2\u501f\u8fc7\u4e66\u7684\u8bfb\u8005
SELECT *
FROM reader
WHERE rno IN(
SELECT rno FROM borrow
);
2.\u6bd4\u8f83\u8fd0\u7b97\u7b26\uff1a\u67e5\u8be2\u5e93\u5b58\u5927\u4e8e\u5e73\u5747\u5e93\u5b58\u7684\u56fe\u4e66
SELECT bno,bname,stock
FROM book
WHERE stock > (
SELECT AVG(stock)
FROM book
);
3.EXISTS\uff1a\u67e5\u8be2\u5b58\u5728\u501f\u9605\u8bb0\u5f55\u7684\u8bfb\u8005
SELECT *
FROM reader r
WHERE EXISTS(
SELECT *
FROM borrow br
WHERE br.rno = r.rno
);
4.ANY\uff1a\u67e5\u8be2\u5e93\u5b58\u5927\u4e8e\u4efb\u610f\u4e00\u672c2018\u5e74\u51fa\u7248\u56fe\u4e66\u5e93\u5b58\u7684\u56fe\u4e66
SELECT bno,bname,stock
FROM book
WHERE stock > ANY(
SELECT stock
FROM book
WHERE pubyear = 2018
);
5.ALL\uff1a\u67e5\u8be2\u5e93\u5b58\u4e0d\u5c11\u4e8e\u6240\u6709\u56fe\u4e66\u5e93\u5b58\u7684\u56fe\u4e66
SELECT bno,bname,stock
FROM book
WHERE stock >= ALL(
SELECT stock
FROM book
);<\/pre>\n\n\n\n10.\u96c6\u5408\u67e5\u8be2<\/h2>\n\n\n\n1.UNION\uff1a\u5408\u5e76\u8bfb\u8005\u59d3\u540d\u548c\u4f5c\u8005\u59d3\u540d\u5e76\u53bb\u91cd
SELECT rname AS name
FROM reader
UNION
SELECT author AS name
FROM book;
2.UNION ALL\uff1a\u5408\u5e76\u8bfb\u8005\u59d3\u540d\u548c\u4f5c\u8005\u59d3\u540d\uff0c\u4e0d\u53bb\u91cd
SELECT rname AS name
FROM reader
UNION ALL
SELECT author AS name
FROM book;
3.\u6a21\u62df INTERSECT\uff1a\u67e5\u8be2\u501f\u8fc7\u4e66\u7684\u8bfb\u8005\u8bc1\u53f7
SELECT rno
FROM reader
WHERE rno IN(
SELECT rno
FROM borrow
);
4.\u6a21\u62df EXCEPT\uff1a\u67e5\u8be2\u6ca1\u6709\u501f\u4e66\u7684\u8bfb\u8005
SELECT rno,rname
FROM reader
WHERE rno NOT IN(
SELECT rno
FROM borrow
);<\/pre>\n\n\n\n11.\u89c6\u56fe\u64cd\u4f5c<\/h2>\n\n\n\n1.\u521b\u5efa\u672a\u5f52\u8fd8\u56fe\u4e66\u89c6\u56fe
CREATE VIEW v_unreturned AS
SELECT br.borrowid, r.rname, b.bname,
br.borrowdate, br.returndate
FROM borrow br
JOIN reader r ON br.rno = r.rno
JOIN book b ON br.bno = b.bno
WHERE br.actualdate IS NULL;
2.\u67e5\u8be2\u89c6\u56fe
SELECT * FROM v_unreturned;
3.\u521b\u5efa\u5b66\u751f\u8bfb\u8005\u89c6\u56fe\uff0c\u5e26 WITH CHECK OPTION
CREATE VIEW v_student_reader AS
SELECT *
FROM reader
WHERE dept LIKE '%\u5b66\u9662%'
WITH CHECK OPTION;
4.\u6d4b\u8bd5\u53ef\u66f4\u65b0\u89c6\u56fe
UPDATE v_student_reader
SET phone = '18800000000'
WHERE rno = 'R2024002';
\u8bf4\u660e\uff1a
\u8be5\u89c6\u56fe\u57fa\u4e8e\u5355\u8868 reader \u521b\u5efa\uff0c\u6ca1\u6709\u805a\u5408\u51fd\u6570\u3001\u5206\u7ec4\u548c\u8fde\u63a5\uff0c\u56e0\u6b64\u5c5e\u4e8e\u53ef\u66f4\u65b0\u89c6\u56fe\u3002
5.\u521b\u5efa\u4e0d\u53ef\u66f4\u65b0\u7684\u805a\u5408\u89c6\u56fe
CREATE VIEW v_press_count AS
SELECT press, COUNT(*) AS total
FROM book
GROUP BY press;
\u8bf4\u660e\uff1a
\u8be5\u89c6\u56fe\u4f7f\u7528\u4e86 GROUP BY \u548c COUNT \u805a\u5408\u51fd\u6570\uff0c\u56e0\u6b64\u4e00\u822c\u4e0d\u80fd\u76f4\u63a5\u66f4\u65b0\u3002
6.\u5220\u9664\u89c6\u56fe
DROP VIEW v_unreturned;
DROP VIEW v_student_reader;
DROP VIEW v_press_count;<\/pre>\n\n\n\n12.\u7d22\u5f15<\/h2>\n\n\n\n1.\u521b\u5efa\u666e\u901a\u7d22\u5f15
CREATE INDEX idx_book_bname
ON book(bname);
2.\u521b\u5efa\u552f\u4e00\u7d22\u5f15
CREATE UNIQUE INDEX idx_reader_phone
ON reader(phone);
3.\u521b\u5efa\u590d\u5408\u7d22\u5f15
CREATE INDEX idx_borrow_rno_bno
ON borrow(rno,bno);
\u67e5\u770b\u7d22\u5f15
SHOW INDEX FROM book;
SHOW INDEX FROM reader;
SHOW INDEX FROM borrow;
\u5220\u9664\u7d22\u5f15
DROP INDEX idx_book_bname ON book;
DROP INDEX idx_reader_phone ON reader;
DROP INDEX idx_borrow_rno_bno ON borrow;<\/pre>\n\n\n\n13.\u6570\u636e\u5b8c\u6574\u6027\u7ea6\u675f\u9a8c\u8bc1\u4e0e\u7ea7\u8054\u64cd\u4f5c<\/h2>\n\n\n\n1.\u5b9e\u4f53\u5b8c\u6574\u6027\u9a8c\u8bc1\uff1a\u4e3b\u952e\u4e0d\u80fd\u4e3a\u7a7a
INSERT INTO book(bno,bname,author,press,pubyear,stock)
VALUES(NULL,'\u6d4b\u8bd5\u4e66','\u6d4b\u8bd5\u4f5c\u8005','\u6d4b\u8bd5\u51fa\u7248\u793e',2020,1);
\u8bf4\u660e\uff1a
bno \u662f book \u8868\u4e3b\u952e\uff0c\u4e3b\u952e\u4e0d\u80fd\u4e3a\u7a7a\uff0c\u56e0\u6b64\u63d2\u5165\u5931\u8d25\u3002
2.\u53c2\u7167\u5b8c\u6574\u6027\u9a8c\u8bc1\uff1a\u63d2\u5165\u4e0d\u5b58\u5728\u7684\u56fe\u4e66\u7f16\u53f7
INSERT INTO borrow(rno,bno,borrowdate,returndate,actualdate)
VALUES('R2024001','B999','2025-05-01','2025-05-15',NULL);
\u8bf4\u660e\uff1a
B999 \u5728 book \u8868\u4e2d\u4e0d\u5b58\u5728\uff0cborrow.bno \u662f\u5916\u952e\uff0c\u56e0\u6b64\u8fdd\u53cd\u53c2\u7167\u5b8c\u6574\u6027\u3002
3.\u7528\u6237\u5b9a\u4e49\u5b8c\u6574\u6027\u9a8c\u8bc1\uff1a\u5e93\u5b58\u4e0d\u80fd\u5c0f\u4e8e0
UPDATE book
SET stock = -1
WHERE bno = 'B001';
\u8bf4\u660e\uff1a
stock \u5b57\u6bb5\u8bbe\u7f6e\u4e86 CHECK(stock>=0)\uff0c\u5e93\u5b58\u4e0d\u80fd\u4e3a\u8d1f\u6570\u3002
4.\u7528\u6237\u5b9a\u4e49\u5b8c\u6574\u6027\u9a8c\u8bc1\uff1a\u5e93\u5b58\u4e0d\u80fd\u5c0f\u4e8e0
UPDATE book
SET stock = -1
WHERE bno = 'B001';
\u8bf4\u660e\uff1a
stock \u5b57\u6bb5\u8bbe\u7f6e\u4e86 CHECK(stock>=0)\uff0c\u5e93\u5b58\u4e0d\u80fd\u4e3a\u8d1f\u6570\u3002
5.ON UPDATE CASCADE \u6d4b\u8bd5
UPDATE reader
SET rno = 'R2024999'
WHERE rno = 'R2024003';
SELECT * FROM borrow
WHERE rno = 'R2024999';
\u8bf4\u660e\uff1a
reader.rno \u66f4\u65b0\u540e\uff0cborrow \u8868\u4e2d\u5bf9\u5e94\u7684\u5916\u952e rno \u4f1a\u81ea\u52a8\u540c\u6b65\u66f4\u65b0\u3002<\/pre>\n\n\n\n14.\u89e6\u53d1\u5668<\/h2>\n\n\n\n\u51c6\u5907\uff1a\u5220\u9664\u65e7\u89e6\u53d1\u5668
DROP TRIGGER IF EXISTS trg_borrow_before_insert;
DROP TRIGGER IF EXISTS trg_return_after_update;
DROP TRIGGER IF EXISTS trg_reader_before_delete;
\u521b\u5efa\u5220\u9664\u8bfb\u8005\u65e5\u5fd7\u8868
CREATE TABLE reader_delete_log(
logid INT AUTO_INCREMENT PRIMARY KEY,
rno CHAR(12),
rname VARCHAR(20),
dept VARCHAR(40),
delete_time DATETIME DEFAULT CURRENT_TIMESTAMP
);
1.\u501f\u4e66\u65f6\u81ea\u52a8\u51cf\u5c11\u5e93\u5b58
DELIMITER \/\/
CREATE TRIGGER trg_borrow_before_insert
BEFORE INSERT ON borrow
FOR EACH ROW
BEGIN
DECLARE v_stock INT;
SELECT stock INTO v_stock
FROM book
WHERE bno = NEW.bno;
IF v_stock <= 0 THEN
SIGNAL SQLSTATE '45000'
SET MESSAGE_TEXT = '\u5e93\u5b58\u4e0d\u8db3\uff0c\u4e0d\u80fd\u501f\u4e66';
ELSE
UPDATE book
SET stock = stock - 1
WHERE bno = NEW.bno;
END IF;
END \/\/
DELIMITER ;
\u6d4b\u8bd5\uff1a
SELECT stock FROM book WHERE bno='B003';
INSERT INTO borrow(rno,bno,borrowdate,returndate,actualdate)
VALUES('R2024002','B003','2025-05-01','2025-05-15',NULL);
SELECT stock FROM book WHERE bno='B003';
2.\u8fd8\u4e66\u65f6\u81ea\u52a8\u589e\u52a0\u5e93\u5b58\u5e76\u8ba1\u7b97\u7f5a\u6b3e
DELIMITER \/\/
CREATE TRIGGER trg_return_after_update
AFTER UPDATE ON borrow
FOR EACH ROW
BEGIN
IF OLD.actualdate IS NULL AND NEW.actualdate IS NOT NULL THEN
UPDATE book
SET stock = stock + 1
WHERE bno = NEW.bno;
UPDATE borrow
SET fine =
CASE
WHEN NEW.actualdate > NEW.returndate
THEN DATEDIFF(NEW.actualdate, NEW.returndate) * 1
ELSE 0
END
WHERE borrowid = NEW.borrowid;
END IF;
END \/\/
DELIMITER ;
\u6d4b\u8bd5\uff1a
UPDATE borrow
SET actualdate = '2025-05-18'
WHERE rno='R2024002'
AND bno='B003'
AND borrowdate='2025-05-01';
SELECT * FROM borrow
WHERE rno='R2024002'
AND bno='B003';
SELECT stock FROM book WHERE bno='B003';
3.\u5220\u9664\u8bfb\u8005\u524d\u8bb0\u5f55\u65e5\u5fd7
DELIMITER \/\/
CREATE TRIGGER trg_reader_before_delete
BEFORE DELETE ON reader
FOR EACH ROW
BEGIN
INSERT INTO reader_delete_log(rno,rname,dept)
VALUES(OLD.rno, OLD.rname, OLD.dept);
END \/\/
DELIMITER ;
\u6d4b\u8bd5\uff1a
INSERT INTO reader
VALUES('R2024888','\u65e5\u5fd7\u6d4b\u8bd5','\u7537','\u6d4b\u8bd5\u5b66\u9662','\u65e0');
DELETE FROM reader
WHERE rno='R2024888';
SELECT * FROM reader_delete_log;<\/pre>\n\n\n\n15.\u6570\u636e\u5b89\u5168\u6027<\/h2>\n\n\n\n1.\u521b\u5efa\u7528\u6237\u5e76\u6388\u4e88\u67e5\u8be2\u6743\u9650
CREATE USER 'lib_user1'@'localhost'
IDENTIFIED BY '123456';
GRANT SELECT
ON library_db.book
TO 'lib_user1'@'localhost';
\u67e5\u770b\u6743\u9650\uff1a
SHOW GRANTS FOR 'lib_user1'@'localhost';
2.\u6388\u4e88\u6743\u9650\u5e76\u5141\u8bb8\u8f6c\u6388\u6743
GRANT SELECT, INSERT
ON library_db.reader
TO 'lib_user1'@'localhost'
WITH GRANT OPTION;
\u8bf4\u660e\uff1a
WITH GRANT OPTION \u8868\u793a\u8be5\u7528\u6237\u53ef\u4ee5\u5c06\u81ea\u5df1\u62e5\u6709\u7684\u6743\u9650\u518d\u6388\u4e88\u5176\u4ed6\u7528\u6237\u3002
3.\u56de\u6536\u6743\u9650
REVOKE INSERT
ON library_db.reader
FROM 'lib_user1'@'localhost';
4.\u521b\u5efa\u89d2\u8272\u5e76\u6388\u6743
CREATE ROLE 'reader_role';
GRANT SELECT
ON library_db.*
TO 'reader_role';
CREATE USER 'lib_user2'@'localhost'
IDENTIFIED BY '123456';
GRANT 'reader_role'
TO 'lib_user2'@'localhost';
SET DEFAULT ROLE 'reader_role'
TO 'lib_user2'@'localhost';<\/pre>\n\n\n\n16.\u89c6\u56fe\u4e0e\u6d3e\u751f\u8868<\/h2>\n\n\n\n1.\u5e26\u805a\u5408\u51fd\u6570\u7684\u89c6\u56fe\uff1a\u7edf\u8ba1\u6bcf\u4e2a\u8bfb\u8005\u501f\u9605\u6b21\u6570
CREATE VIEW v_reader_borrow_count AS
SELECT r.rno, r.rname, COUNT(br.borrowid) AS borrow_count
FROM reader r
LEFT JOIN borrow br
ON r.rno = br.rno
GROUP BY r.rno, r.rname;
\u67e5\u8be2\uff1a
SELECT * FROM v_reader_borrow_count;
2.\u6d3e\u751f\u8868\uff1a\u67e5\u8be2\u501f\u9605\u6b21\u6570\u5927\u4e8e1\u7684\u8bfb\u8005
SELECT *
FROM (
SELECT rno, COUNT(*) AS borrow_count
FROM borrow
GROUP BY rno
) AS t
WHERE t.borrow_count > 1;
3.WITH \u5b50\u53e5\u7edf\u8ba1\u6bcf\u4f4d\u8bfb\u8005\u501f\u9605\u6570\u91cf
WITH reader_count AS (
SELECT rno, COUNT(*) AS total
FROM borrow
GROUP BY rno
)
SELECT r.rno, r.rname, rc.total
FROM reader r
LEFT JOIN reader_count rc
ON r.rno = rc.rno;
4.WITH \u5b50\u53e5\uff1a\u67e5\u8be2\u672a\u5f52\u8fd8\u56fe\u4e66
WITH unreturned AS (
SELECT br.borrowid, r.rname, b.bname,
br.borrowdate, br.returndate
FROM borrow br
JOIN reader r ON br.rno = r.rno
JOIN book b ON br.bno = b.bno
WHERE br.actualdate IS NULL
)
SELECT * FROM unreturned;<\/pre>\n\n\n\n17.\u6269\u5c55\u601d\u8003<\/h2>\n\n\n\n\n- \u5982\u4f55\u5904\u7406\u5206\u7c7b\u5b9e\u4f53\u7684\u81ea\u5173\u8054\uff1f<\/li>\n<\/ol>\n\n\n\n
\u5206\u7c7b\u5b9e\u4f53\u5b58\u5728\u201c\u4e0a\u7ea7\u5206\u7c7b\u201d\u548c\u201c\u4e0b\u7ea7\u5206\u7c7b\u201d\u7684\u5173\u7cfb\uff0c\u56e0\u6b64\u53ef\u4ee5\u5728 category \u8868\u4e2d\u8bbe\u7f6e parentid \u5b57\u6bb5\u3002
category(
cid,
cname,
parentid
)
\u5176\u4e2d cid \u662f\u5206\u7c7b\u7f16\u53f7\uff0cparentid \u662f\u4e0a\u7ea7\u5206\u7c7b\u7f16\u53f7\uff0c\u540c\u65f6 parentid \u4e5f\u662f\u6307\u5411 category.cid \u7684\u5916\u952e\u3002
\u5982\u679c\u67d0\u5206\u7c7b\u6ca1\u6709\u4e0a\u7ea7\u5206\u7c7b\uff0c\u5219 parentid \u53ef\u4ee5\u4e3a\u7a7a\u3002
\u8fd9\u79cd\u8bbe\u8ba1\u53ef\u4ee5\u8868\u793a\u6811\u5f62\u7ed3\u6784\uff0c\u4f8b\u5982\uff1a
\u56fe\u4e66
\u251c\u2500\u2500 \u8ba1\u7b97\u673a
\u2502 \u251c\u2500\u2500 \u6570\u636e\u5e93
\u2502 \u2514\u2500\u2500 \u7f51\u7edc\u6280\u672f
\u2514\u2500\u2500 \u6587\u5b66
\u2514\u2500\u2500 \u79d1\u5e7b\u5c0f\u8bf4<\/pre>\n\n\n\n
\n\n\n\n2. \u501f\u9605\u5173\u7cfb\u662f\u5426\u53ef\u80fd\u5b58\u5728\u6570\u636e\u5197\u4f59\uff1f<\/h2>\n\n\n\n\u501f\u9605\u8868\u5982\u679c\u53ea\u4fdd\u5b58 rno\u3001bno\u3001borrowdate\u3001returndate\u3001actualdate \u7b49\u4fe1\u606f\uff0c\u5219\u5197\u4f59\u8f83\u5c11\u3002
\u4f46\u662f\u5982\u679c\u5728 borrow \u8868\u4e2d\u540c\u65f6\u4fdd\u5b58\u8bfb\u8005\u59d3\u540d rname\u3001\u56fe\u4e66\u540d\u79f0 bname\u3001\u51fa\u7248\u793e press \u7b49\u4fe1\u606f\uff0c\u5c31\u4f1a\u4ea7\u751f\u6570\u636e\u5197\u4f59\u3002
\u4f8b\u5982\uff1a
borrow(borrowid, rno, rname, bno, bname, borrowdate)
\u5176\u4e2d rname \u4f9d\u8d56 rno\uff0cbname \u4f9d\u8d56 bno\uff0c\u800c\u4e0d\u662f\u76f4\u63a5\u4f9d\u8d56 borrowid\uff0c\u4f1a\u4ea7\u751f\u4f20\u9012\u4f9d\u8d56\u3002
\u89c4\u8303\u5316\u65b9\u6848\uff1a
\u5c06\u8bfb\u8005\u4fe1\u606f\u4fdd\u5b58\u5728 reader \u8868\uff1b
\u5c06\u56fe\u4e66\u4fe1\u606f\u4fdd\u5b58\u5728 book \u8868\uff1b
borrow \u8868\u53ea\u4fdd\u5b58\u8bfb\u8005\u8bc1\u53f7\u548c\u56fe\u4e66\u7f16\u53f7\u4f5c\u4e3a\u5916\u952e\u3002<\/pre>\n\n\n\n
\n\n\n\n3. \u5982\u4f55\u9632\u6b62\u5e93\u5b58\u4e3a\u8d1f\u6570\uff1f<\/h2>\n\n\n\n\u53ef\u4ee5\u4ece\u4e24\u4e2a\u65b9\u9762\u9632\u6b62\u5e93\u5b58\u4e3a\u8d1f\u6570\uff1a
\u7b2c\u4e00\uff0c\u5728 book \u8868\u4e2d\u8bbe\u7f6e CHECK(stock >= 0) \u7ea6\u675f\uff0c\u4fdd\u8bc1\u5e93\u5b58\u4e0d\u80fd\u5c0f\u4e8e0\u3002
\u7b2c\u4e8c\uff0c\u5728\u501f\u4e66\u89e6\u53d1\u5668\u4e2d\u5224\u65ad\u5e93\u5b58\u6570\u91cf\u3002
\u5f53\u63d2\u5165 borrow \u501f\u9605\u8bb0\u5f55\u65f6\uff0c\u5148\u67e5\u8be2\u56fe\u4e66\u5e93\u5b58\u3002
\u5982\u679c\u5e93\u5b58\u5c0f\u4e8e\u7b49\u4e8e0\uff0c\u5219\u4f7f\u7528 SIGNAL \u629b\u51fa\u9519\u8bef\uff0c\u963b\u6b62\u501f\u4e66\u64cd\u4f5c\uff1b
\u5982\u679c\u5e93\u5b58\u5927\u4e8e0\uff0c\u5219\u5141\u8bb8\u501f\u9605\uff0c\u5e76\u81ea\u52a8\u5c06\u5e93\u5b58\u51cf1\u3002
\u8fd9\u6837\u53ef\u4ee5\u4fdd\u8bc1\u501f\u4e66\u65f6\u4e0d\u4f1a\u51fa\u73b0\u5e93\u5b58\u4e3a\u8d1f\u6570\u7684\u60c5\u51b5\u3002<\/pre>\n\n\n\n
\n\n\n\n4. \u9884\u7ea6\u56fe\u4e66\u529f\u80fd\u9700\u8981\u589e\u52a0\u54ea\u4e9b\u5b9e\u4f53\u548c\u5173\u7cfb\uff1f<\/h2>\n\n\n\n\u5982\u679c\u7cfb\u7edf\u652f\u6301\u9884\u7ea6\u56fe\u4e66\u529f\u80fd\uff0c\u53ef\u4ee5\u589e\u52a0 reservation \u9884\u7ea6\u8868\u3002
reservation(
reserveid,
rno,
bno,
reservedate,
status
)
\u5176\u4e2d\uff1a
reserveid \u8868\u793a\u9884\u7ea6\u7f16\u53f7\uff1b
rno \u662f\u8bfb\u8005\u8bc1\u53f7\uff0c\u5916\u952e\u5f15\u7528 reader.rno\uff1b
bno \u662f\u56fe\u4e66\u7f16\u53f7\uff0c\u5916\u952e\u5f15\u7528 book.bno\uff1b
reservedate \u8868\u793a\u9884\u7ea6\u65e5\u671f\uff1b
status \u8868\u793a\u9884\u7ea6\u72b6\u6001\uff0c\u5982\u201c\u9884\u7ea6\u4e2d\u201d\u201c\u5df2\u53d6\u6d88\u201d\u201c\u5df2\u5b8c\u6210\u201d\u3002
\u65b0\u589e\u5173\u7cfb\uff1a
\u4e00\u4e2a\u8bfb\u8005\u53ef\u4ee5\u9884\u7ea6\u591a\u672c\u56fe\u4e66\uff1b
\u4e00\u672c\u56fe\u4e66\u53ef\u4ee5\u88ab\u591a\u4e2a\u8bfb\u8005\u9884\u7ea6\uff1b
\u8bfb\u8005\u548c\u56fe\u4e66\u4e4b\u95f4\u901a\u8fc7 reservation \u8868\u5f62\u6210 m:n \u8054\u7cfb\u3002<\/pre>\n\n\n\n
\n\n\n\n5. \u4e3a\u4ec0\u4e48\u9075\u5faa\u6700\u5c0f\u6743\u9650\u539f\u5219\uff1f<\/h2>\n\n\n\n\u6700\u5c0f\u6743\u9650\u539f\u5219\u662f\u6307\u53ea\u7ed9\u7528\u6237\u5b8c\u6210\u5de5\u4f5c\u6240\u5fc5\u9700\u7684\u6743\u9650\uff0c\u4e0d\u6388\u4e88\u591a\u4f59\u6743\u9650\u3002
\u5728\u672c\u5b9e\u9a8c\u4e2d\uff0c\u5982\u679c\u67d0\u7528\u6237\u53ea\u8d1f\u8d23\u67e5\u8be2\u56fe\u4e66\u4fe1\u606f\uff0c\u5219\u53ea\u6388\u4e88 SELECT \u6743\u9650\u5373\u53ef\uff0c\u4e0d\u5e94\u8be5\u6388\u4e88 INSERT\u3001UPDATE\u3001DELETE \u7b49\u6743\u9650\u3002
\u4f8b\u5982\uff1a
GRANT SELECT ON library_db.book TO 'lib_user1'@'localhost';
\u8fd9\u6837\u53ef\u4ee5\u9632\u6b62\u7528\u6237\u8bef\u5220\u3001\u8bef\u6539\u6570\u636e\uff0c\u63d0\u9ad8\u6570\u636e\u5e93\u5b89\u5168\u6027\u3002
\u5982\u679c\u540e\u7eed\u4e0d\u518d\u9700\u8981\u67d0\u9879\u6743\u9650\uff0c\u8fd8\u53ef\u4ee5\u4f7f\u7528 REVOKE \u56de\u6536\u6743\u9650\u3002<\/pre>\n\n\n\n
\n\n\n\n6. \u5e76\u53d1\u501f\u9605\u5e93\u5b58\u4ec5\u52691\u672c\u7684\u56fe\u4e66\u4f1a\u4ea7\u751f\u4ec0\u4e48\u95ee\u9898\uff1f\u5982\u4f55\u89e3\u51b3\uff1f<\/h2>\n\n\n\n\u5f53\u591a\u7528\u6237\u540c\u65f6\u501f\u9605\u540c\u4e00\u672c\u5e93\u5b58\u4ec5\u52691\u672c\u7684\u56fe\u4e66\u65f6\uff0c\u53ef\u80fd\u51fa\u73b0\u8d85\u5356\u95ee\u9898\u3002
\u4f8b\u5982\u4e24\u4e2a\u7528\u6237\u540c\u65f6\u8bfb\u53d6\u5e93\u5b58 stock=1\uff0c\u90fd\u8ba4\u4e3a\u53ef\u4ee5\u501f\u9605\uff0c\u7136\u540e\u540c\u65f6\u63d2\u5165\u501f\u9605\u8bb0\u5f55\u5e76\u6267\u884c\u5e93\u5b58\u51cf1\uff0c\u6700\u7ec8\u53ef\u80fd\u5bfc\u81f4\u5e93\u5b58\u5f02\u5e38\u6216\u51fa\u73b0\u8d85\u989d\u501f\u9605\u3002
\u89e3\u51b3\u65b9\u6cd5\uff1a
1. \u4f7f\u7528\u4e8b\u52a1\u4fdd\u8bc1\u501f\u4e66\u64cd\u4f5c\u7684\u539f\u5b50\u6027\uff1b
2. \u4f7f\u7528 SELECT ... FOR UPDATE \u5bf9\u56fe\u4e66\u5e93\u5b58\u8bb0\u5f55\u52a0\u884c\u7ea7\u9501\uff1b
3. \u5728\u89e6\u53d1\u5668\u4e2d\u5224\u65ad\u5e93\u5b58\u662f\u5426\u5927\u4e8e0\uff1b
4. \u7ed9 stock \u5b57\u6bb5\u8bbe\u7f6e CHECK(stock >= 0) \u7ea6\u675f\u3002
\u793a\u4f8b\uff1a
START TRANSACTION;
SELECT stock
FROM book
WHERE bno='B001'
FOR UPDATE;
UPDATE book
SET stock = stock - 1
WHERE bno='B001'
AND stock > 0;
INSERT INTO borrow(rno,bno,borrowdate,returndate)
VALUES('R2024001','B001','2025-05-01','2025-05-15');
COMMIT;
\u8fd9\u6837\u53ef\u4ee5\u907f\u514d\u591a\u4e2a\u7528\u6237\u540c\u65f6\u4fee\u6539\u5e93\u5b58\u5bfc\u81f4\u6570\u636e\u4e0d\u4e00\u81f4\u3002<\/pre>\n\n\n\n
\n\n\n\n\u5b9e\u9a8c\u603b\u7ed3<\/h1>\n\n\n\n \u901a\u8fc7\u672c\u6b21\u56fe\u4e66\u501f\u9605\u7ba1\u7406\u7cfb\u7edf\u7efc\u5408\u5b9e\u9a8c\uff0c\u6211\u7cfb\u7edf\u5730\u5b8c\u6210\u4e86\u6570\u636e\u5e93\u8bbe\u8ba1\u4e0e\u5b9e\u73b0\u7684\u5168\u8fc7\u7a0b\u3002\u5b9e\u9a8c\u4ece\u9700\u6c42\u5206\u6790\u5f00\u59cb\uff0c\u9010\u6b65\u5b8c\u6210 E-R \u56fe\u8bbe\u8ba1\u3001\u5173\u7cfb\u6a21\u5f0f\u8f6c\u6362\u3001\u7269\u7406\u8868\u7ed3\u6784\u8bbe\u8ba1\u3001\u6570\u636e\u63d2\u5165\u3001\u67e5\u8be2\u64cd\u4f5c\u3001\u89c6\u56fe\u3001\u7d22\u5f15\u3001\u5b8c\u6574\u6027\u7ea6\u675f\u3001\u89e6\u53d1\u5668\u548c\u6743\u9650\u7ba1\u7406\u7b49\u5185\u5bb9\uff0c\u4f7f\u6211\u5bf9\u6570\u636e\u5e93\u5e94\u7528\u7cfb\u7edf\u7684\u8bbe\u8ba1\u6d41\u7a0b\u6709\u4e86\u66f4\u52a0\u5b8c\u6574\u7684\u8ba4\u8bc6\u3002
\u200b
\u5728\u5b9e\u9a8c\u8fc7\u7a0b\u4e2d\uff0c\u6211\u9996\u5148\u6839\u636e\u56fe\u4e66\u9986\u4e1a\u52a1\u9700\u6c42\u5206\u6790\u51fa\u56fe\u4e66\u3001\u8bfb\u8005\u3001\u501f\u9605\u3001\u51fa\u7248\u793e\u3001\u5206\u7c7b\u7b49\u5b9e\u4f53\uff0c\u5e76\u660e\u786e\u4e86\u5b83\u4eec\u4e4b\u95f4\u7684\u8054\u7cfb\u7c7b\u578b\u3002\u4f8b\u5982\uff0c\u51fa\u7248\u793e\u4e0e\u56fe\u4e66\u4e4b\u95f4\u662f\u4e00\u5bf9\u591a\u5173\u7cfb\uff0c\u5206\u7c7b\u4e0e\u56fe\u4e66\u4e4b\u95f4\u662f\u4e00\u5bf9\u591a\u5173\u7cfb\uff0c\u8bfb\u8005\u4e0e\u56fe\u4e66\u4e4b\u95f4\u901a\u8fc7\u501f\u9605\u8868\u5f62\u6210\u591a\u5bf9\u591a\u5173\u7cfb\u3002\u901a\u8fc7 E-R \u56fe\u8bbe\u8ba1\uff0c\u6211\u8fdb\u4e00\u6b65\u7406\u89e3\u4e86\u6982\u5ff5\u7ed3\u6784\u8bbe\u8ba1\u5728\u6570\u636e\u5e93\u5f00\u53d1\u4e2d\u7684\u91cd\u8981\u4f5c\u7528\u3002
\u200b
\u5728\u903b\u8f91\u7ed3\u6784\u8bbe\u8ba1\u9636\u6bb5\uff0c\u6211\u5c06 E-R \u56fe\u8f6c\u6362\u4e3a\u5173\u7cfb\u6a21\u5f0f\uff0c\u5e76\u5206\u6790\u5404\u8868\u662f\u5426\u6ee1\u8db3\u7b2c\u4e09\u8303\u5f0f\u3002\u901a\u8fc7\u89c4\u8303\u5316\u8bbe\u8ba1\uff0c\u907f\u514d\u4e86\u5728\u501f\u9605\u8868\u4e2d\u91cd\u590d\u4fdd\u5b58\u8bfb\u8005\u59d3\u540d\u3001\u56fe\u4e66\u540d\u79f0\u7b49\u4fe1\u606f\uff0c\u51cf\u5c11\u4e86\u6570\u636e\u5197\u4f59\uff0c\u63d0\u9ad8\u4e86\u6570\u636e\u4e00\u81f4\u6027\u3002\u5728\u7269\u7406\u8bbe\u8ba1\u9636\u6bb5\uff0c\u6211\u4f7f\u7528 SQL \u521b\u5efa\u6570\u636e\u5e93\u548c\u6570\u636e\u8868\uff0c\u8bbe\u7f6e\u4e86\u4e3b\u952e\u3001\u5916\u952e\u3001\u975e\u7a7a\u3001\u9ed8\u8ba4\u503c\u548c CHECK \u7ea6\u675f\uff0c\u5bf9\u5b9e\u4f53\u5b8c\u6574\u6027\u3001\u53c2\u7167\u5b8c\u6574\u6027\u548c\u7528\u6237\u5b9a\u4e49\u5b8c\u6574\u6027\u6709\u4e86\u66f4\u6df1\u523b\u7684\u7406\u89e3\u3002
\u200b
\u5728\u6570\u636e\u64cd\u4f5c\u90e8\u5206\uff0c\u6211\u7ec3\u4e60\u4e86 INSERT\u3001UPDATE\u3001DELETE \u548c SELECT \u8bed\u53e5\uff0c\u5e76\u5b8c\u6210\u4e86\u57fa\u7840\u67e5\u8be2\u3001\u805a\u5408\u67e5\u8be2\u3001\u591a\u8868\u8fde\u63a5\u67e5\u8be2\u3001\u5d4c\u5957\u67e5\u8be2\u548c\u96c6\u5408\u67e5\u8be2\u7b49\u5185\u5bb9\u3002\u901a\u8fc7\u8fd9\u4e9b\u7ec3\u4e60\uff0c\u6211\u638c\u63e1\u4e86 SQL \u67e5\u8be2\u8bed\u53e5\u7684\u5e38\u89c1\u5199\u6cd5\uff0c\u5c24\u5176\u662f\u591a\u8868\u8fde\u63a5\u548c\u5d4c\u5957\u67e5\u8be2\u7684\u4f7f\u7528\u65b9\u6cd5\u3002\u5b9e\u9a8c\u4e2d\u8fd8\u521b\u5efa\u4e86\u89c6\u56fe\u548c\u7d22\u5f15\uff0c\u7406\u89e3\u4e86\u89c6\u56fe\u53ef\u4ee5\u7b80\u5316\u590d\u6742\u67e5\u8be2\uff0c\u7d22\u5f15\u53ef\u4ee5\u63d0\u9ad8\u67e5\u8be2\u6548\u7387\uff0c\u4f46\u4e5f\u4f1a\u589e\u52a0\u7ef4\u62a4\u6210\u672c\u3002
\u200b
\u5728\u89e6\u53d1\u5668\u90e8\u5206\uff0c\u6211\u5b9e\u73b0\u4e86\u501f\u4e66\u81ea\u52a8\u51cf\u5c11\u5e93\u5b58\u3001\u8fd8\u4e66\u81ea\u52a8\u589e\u52a0\u5e93\u5b58\u5e76\u8ba1\u7b97\u7f5a\u6b3e\u3001\u5220\u9664\u8bfb\u8005\u524d\u8bb0\u5f55\u65e5\u5fd7\u7b49\u529f\u80fd\u3002\u901a\u8fc7\u89e6\u53d1\u5668\u5b9e\u9a8c\uff0c\u6211\u8ba4\u8bc6\u5230\u6570\u636e\u5e93\u4e0d\u4ec5\u53ef\u4ee5\u5b58\u50a8\u6570\u636e\uff0c\u8fd8\u53ef\u4ee5\u5728\u7279\u5b9a\u64cd\u4f5c\u53d1\u751f\u65f6\u81ea\u52a8\u6267\u884c\u4e00\u4e9b\u4e1a\u52a1\u903b\u8f91\u3002\u5b9e\u9a8c\u8fc7\u7a0b\u4e2d\u4e5f\u9047\u5230\u4e86\u4e00\u4e9b\u95ee\u9898\uff0c\u4f8b\u5982\u5916\u952e\u7ea6\u675f\u5bfc\u81f4\u6570\u636e\u65e0\u6cd5\u5220\u9664\u3001CHECK \u7ea6\u675f\u63d2\u5165\u5931\u8d25\u3001\u89e6\u53d1\u5668\u8bed\u6cd5\u9519\u8bef\u7b49\u3002\u901a\u8fc7\u67e5\u770b\u9519\u8bef\u4fe1\u606f\u3001\u4fee\u6539 SQL \u8bed\u53e5\u548c\u53cd\u590d\u6d4b\u8bd5\uff0c\u6700\u7ec8\u89e3\u51b3\u4e86\u8fd9\u4e9b\u95ee\u9898\u3002
\u200b
\u901a\u8fc7\u672c\u6b21\u5b9e\u9a8c\uff0c\u6211\u4e0d\u4ec5\u5de9\u56fa\u4e86\u6570\u636e\u5e93\u7406\u8bba\u77e5\u8bc6\uff0c\u4e5f\u63d0\u9ad8\u4e86 SQL \u7f16\u5199\u80fd\u529b\u548c\u6570\u636e\u5e93\u8c03\u8bd5\u80fd\u529b\u3002\u4eca\u540e\u5728\u8bbe\u8ba1\u6570\u636e\u5e93\u7cfb\u7edf<\/pre>\n","protected":false},"excerpt":{"rendered":"\u6570\u636e\u5e93\u7efc\u5408\u5b9e\u9a8c 1.\u9700\u6c42\u5206\u6790 \u67d0\u5927\u578b\u56fe\u4e66\u9986\u9700\u8981\u5f00\u53d1\u4e00\u5957\u6570\u5b57\u5316\u501f\u9605\u7ba1\u7406\u7cfb\u7edf\uff0c\u4e3b\u8981\u4e1a\u52a1\u9700\u6c42\u5982\u4e0b\uff1a \u56fe\u4e66\u4fe1\u606f\uff1a\u8bb0\u5f55\u56fe […]<\/p>\n","protected":false},"author":1,"featured_media":448,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[9],"tags":[],"class_list":["post-446","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-wenzhang"],"_links":{"self":[{"href":"https:\/\/fg2025.cn\/index.php\/wp-json\/wp\/v2\/posts\/446","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/fg2025.cn\/index.php\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/fg2025.cn\/index.php\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/fg2025.cn\/index.php\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/fg2025.cn\/index.php\/wp-json\/wp\/v2\/comments?post=446"}],"version-history":[{"count":0,"href":"https:\/\/fg2025.cn\/index.php\/wp-json\/wp\/v2\/posts\/446\/revisions"}],"wp:attachment":[{"href":"https:\/\/fg2025.cn\/index.php\/wp-json\/wp\/v2\/media?parent=446"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/fg2025.cn\/index.php\/wp-json\/wp\/v2\/categories?post=446"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/fg2025.cn\/index.php\/wp-json\/wp\/v2\/tags?post=446"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}
select * from book;
2.\u67e5\u8be2\u5e93\u5b58\u5927\u4e8e3\u7684\u56fe\u4e66
SELECT bno,bname,stock
FROM book
WHERE stock > 3;
3.\u67e5\u8be22018\u5e74\u51fa\u7248\u4e14\u5e93\u5b58\u4e0d\u5c11\u4e8e4\u672c\u7684\u56fe\u4e66
SELECT bno,bname,pubyear,stock
FROM book
WHERE pubyear = 2018 AND stock >= 4;
4.\u67e5\u8be22015\u5e74\u81f32018\u5e74\u51fa\u7248\u7684\u56fe\u4e66
SELECT bno,bname,pubyear
FROM book
WHERE pubyear BETWEEN 2015 AND 2018;
5.\u67e5\u8be2\u51fa\u7248\u793e\u4e3a\u201c\u91cd\u5e86\u51fa\u7248\u793e\u201d\u6216\u201c\u9ad8\u7b49\u6559\u80b2\u51fa\u7248\u793e\u201d\u7684\u56fe\u4e66
SELECT bno,bname,press
FROM book
WHERE press IN('\u91cd\u5e86\u51fa\u7248\u793e','\u9ad8\u7b49\u6559\u80b2\u51fa\u7248\u793e');
6.\u67e5\u8be2\u4e66\u540d\u4e2d\u5305\u542b\u201c\u8ba1\u7b97\u673a\u201d\u7684\u56fe\u4e66
SELECT bno,bname
FROM book
WHERE bname LIKE '%\u8ba1\u7b97\u673a%';
7.\u67e5\u8be2\u5c1a\u672a\u5f52\u8fd8\u7684\u501f\u9605\u8bb0\u5f55
SELECT *
FROM borrow
WHERE actualdate IS NULL;
8.\u6309\u5e93\u5b58\u6570\u91cf\u964d\u5e8f\u67e5\u8be2\u56fe\u4e66
SELECT bno,bname,stock
FROM book
ORDER BY stock DESC;
9.\u67e5\u8be2\u5e93\u5b58\u6700\u591a\u7684\u524d2\u672c\u56fe\u4e66
SELECT bno,bname,stock
FROM book
ORDER BY stock DESC
LIMIT 2;
10.\u67e5\u8be2\u6240\u6709\u4e0d\u540c\u7684\u51fa\u7248\u793e
SELECT DISTINCT press
FROM book;<\/pre>\n\n\n\n
6.\u6570\u636e\u66f4\u65b0\uff08update\/delete\uff09<\/h2>\n\n\n\n 1.\u5c06BOO1\u7684\u5e93\u5b58\u4fee\u6539\u4e3a6
UPDATE book
SET stock = 6
WHERE bno = 'B001';
\u200b
SELECT * FROM book WHERE bno='B001';
2.\u4fee\u6539\u5f20\u660e\u7684\u9662\u7cfb\u548c\u7535\u8bdd
UPDATE reader
SET dept = '\u4eba\u5de5\u667a\u80fd\u5b66\u9662',
phone = '18888888888'
WHERE rno = 'R2024001';
\u200b
SELECT * FROM reader WHERE rno='R2024001';
3.\u5c062018\u5e74\u51fa\u7248\u56fe\u4e66\u5e93\u5b58\u7edf\u4e00\u589e\u52a01
UPDATE book
SET stock = stock + 1
WHERE pubyear = 2018;
\u200b
SELECT * FROM book WHERE pubyear=2018;
4.\u5220\u9664\u4e00\u4e2a\u6d4b\u8bd5\u8bfb\u8005
INSERT INTO reader
VALUES('R2024999','\u6d4b\u8bd5\u8bfb\u8005','\u7537','\u6d4b\u8bd5\u5b66\u9662','\u65e0');
\u200b
DELETE FROM reader
WHERE rno = 'R2024999';
5.\u4e8b\u52a1\u63a7\u5236\uff1a\u66f4\u65b0\u540e\u56de\u6eda
START TRANSACTION;
\u200b
UPDATE book
SET stock = stock - 1
WHERE bno = 'B003';
\u200b
SELECT * FROM book WHERE bno='B003';
\u200b
ROLLBACK;
\u200b
SELECT * FROM book WHERE bno='B003';<\/pre>\n\n\n\n7.\u805a\u5408\u67e5\u8be2\u4e0e\u5206\u7ec4\u7edf\u8ba1<\/h2>\n\n\n\n 1.\u7edf\u8ba1\u56fe\u4e66\u603b\u6570
select count(*) as \u56fe\u4e66\u603b\u6570 from book;
2.\u7edf\u8ba1\u56fe\u4e66\u5e93\u5b58\u603b\u91cf
select sum(stock) as \u5e93\u5b58\u603b\u91cf from book;
3.\u7edf\u8ba1\u5e73\u5747\u5e93\u5b58
select avg(stock) as \u5e73\u5747\u5e93\u5b58 from book;
4.\u67e5\u8be2\u6700\u5927\u5e93\u5b58\u548c\u6700\u5c0f\u5e93\u5b58
SELECT MAX(stock) AS \u6700\u5927\u5e93\u5b58,
MIN(stock) AS \u6700\u5c0f\u5e93\u5b58
FROM book;
5.\u6309\u51fa\u7248\u793e\u7edf\u8ba1\u56fe\u4e66\u6570\u91cf\uff0c\u5e76\u7b5b\u9009\u6570\u91cf\u5927\u4e8e\u7b49\u4e8e1\u7684\u51fa\u7248\u793e
SELECT press, COUNT(*) AS \u56fe\u4e66\u6570\u91cf
FROM book
GROUP BY press
HAVING COUNT(*) >= 1;<\/pre>\n\n\n\n8.\u591a\u8868\u8fde\u63a5\u67e5\u8be2<\/h2>\n\n\n\n1.\u7b49\u503c\u8fde\u63a5\uff1a\u67e5\u8be2\u8bfb\u8005\u59d3\u540d\u548c\u6240\u501f\u56fe\u4e66
SELECT reader.rname, book.bname
FROM reader, borrow, book
WHERE reader.rno = borrow.rno
AND borrow.bno = book.bno;
2.\u5185\u8fde\u63a5\uff1a\u67e5\u8be2\u501f\u9605\u8bb0\u5f55\u8be6\u60c5
SELECT r.rname, b.bname, br.borrowdate, br.returndate
FROM borrow br
JOIN reader r ON br.rno = r.rno
JOIN book b ON br.bno = b.bno;
3.\u5de6\u5916\u8fde\u63a5\uff1a\u67e5\u8be2\u6240\u6709\u8bfb\u8005\u53ca\u5176\u501f\u9605\u8bb0\u5f55
SELECT r.rno, r.rname, br.borrowid, br.bno
FROM reader r
LEFT JOIN borrow br
ON r.rno = br.rno;
4.\u53f3\u5916\u8fde\u63a5\uff1a\u67e5\u8be2\u6240\u6709\u501f\u9605\u8bb0\u5f55\u53ca\u8bfb\u8005\u4fe1\u606f
SELECT r.rname, br.borrowid, br.bno
FROM reader r
RIGHT JOIN borrow br
ON r.rno = br.rno;
5.\u81ea\u8eab\u8fde\u63a5\uff1a\u67e5\u8be2\u540c\u4e00\u5e74\u51fa\u7248\u7684\u4e0d\u540c\u56fe\u4e66
SELECT a.bname AS \u56fe\u4e661,
b.bname AS \u56fe\u4e662,
a.pubyear AS \u51fa\u7248\u5e74\u4efd
FROM book a
JOIN book b
ON a.pubyear = b.pubyear
AND a.bno < b.bno;<\/pre>\n\n\n\n9.\u5d4c\u5957\u67e5\u8be2<\/h2>\n\n\n\n1.IN\uff1a\u67e5\u8be2\u501f\u8fc7\u4e66\u7684\u8bfb\u8005
SELECT *
FROM reader
WHERE rno IN(
SELECT rno FROM borrow
);
2.\u6bd4\u8f83\u8fd0\u7b97\u7b26\uff1a\u67e5\u8be2\u5e93\u5b58\u5927\u4e8e\u5e73\u5747\u5e93\u5b58\u7684\u56fe\u4e66
SELECT bno,bname,stock
FROM book
WHERE stock > (
SELECT AVG(stock)
FROM book
);
3.EXISTS\uff1a\u67e5\u8be2\u5b58\u5728\u501f\u9605\u8bb0\u5f55\u7684\u8bfb\u8005
SELECT *
FROM reader r
WHERE EXISTS(
SELECT *
FROM borrow br
WHERE br.rno = r.rno
);
4.ANY\uff1a\u67e5\u8be2\u5e93\u5b58\u5927\u4e8e\u4efb\u610f\u4e00\u672c2018\u5e74\u51fa\u7248\u56fe\u4e66\u5e93\u5b58\u7684\u56fe\u4e66
SELECT bno,bname,stock
FROM book
WHERE stock > ANY(
SELECT stock
FROM book
WHERE pubyear = 2018
);
5.ALL\uff1a\u67e5\u8be2\u5e93\u5b58\u4e0d\u5c11\u4e8e\u6240\u6709\u56fe\u4e66\u5e93\u5b58\u7684\u56fe\u4e66
SELECT bno,bname,stock
FROM book
WHERE stock >= ALL(
SELECT stock
FROM book
);<\/pre>\n\n\n\n10.\u96c6\u5408\u67e5\u8be2<\/h2>\n\n\n\n1.UNION\uff1a\u5408\u5e76\u8bfb\u8005\u59d3\u540d\u548c\u4f5c\u8005\u59d3\u540d\u5e76\u53bb\u91cd
SELECT rname AS name
FROM reader
UNION
SELECT author AS name
FROM book;
2.UNION ALL\uff1a\u5408\u5e76\u8bfb\u8005\u59d3\u540d\u548c\u4f5c\u8005\u59d3\u540d\uff0c\u4e0d\u53bb\u91cd
SELECT rname AS name
FROM reader
UNION ALL
SELECT author AS name
FROM book;
3.\u6a21\u62df INTERSECT\uff1a\u67e5\u8be2\u501f\u8fc7\u4e66\u7684\u8bfb\u8005\u8bc1\u53f7
SELECT rno
FROM reader
WHERE rno IN(
SELECT rno
FROM borrow
);
4.\u6a21\u62df EXCEPT\uff1a\u67e5\u8be2\u6ca1\u6709\u501f\u4e66\u7684\u8bfb\u8005
SELECT rno,rname
FROM reader
WHERE rno NOT IN(
SELECT rno
FROM borrow
);<\/pre>\n\n\n\n11.\u89c6\u56fe\u64cd\u4f5c<\/h2>\n\n\n\n1.\u521b\u5efa\u672a\u5f52\u8fd8\u56fe\u4e66\u89c6\u56fe
CREATE VIEW v_unreturned AS
SELECT br.borrowid, r.rname, b.bname,
br.borrowdate, br.returndate
FROM borrow br
JOIN reader r ON br.rno = r.rno
JOIN book b ON br.bno = b.bno
WHERE br.actualdate IS NULL;
2.\u67e5\u8be2\u89c6\u56fe
SELECT * FROM v_unreturned;
3.\u521b\u5efa\u5b66\u751f\u8bfb\u8005\u89c6\u56fe\uff0c\u5e26 WITH CHECK OPTION
CREATE VIEW v_student_reader AS
SELECT *
FROM reader
WHERE dept LIKE '%\u5b66\u9662%'
WITH CHECK OPTION;
4.\u6d4b\u8bd5\u53ef\u66f4\u65b0\u89c6\u56fe
UPDATE v_student_reader
SET phone = '18800000000'
WHERE rno = 'R2024002';
\u8bf4\u660e\uff1a
\u8be5\u89c6\u56fe\u57fa\u4e8e\u5355\u8868 reader \u521b\u5efa\uff0c\u6ca1\u6709\u805a\u5408\u51fd\u6570\u3001\u5206\u7ec4\u548c\u8fde\u63a5\uff0c\u56e0\u6b64\u5c5e\u4e8e\u53ef\u66f4\u65b0\u89c6\u56fe\u3002
5.\u521b\u5efa\u4e0d\u53ef\u66f4\u65b0\u7684\u805a\u5408\u89c6\u56fe
CREATE VIEW v_press_count AS
SELECT press, COUNT(*) AS total
FROM book
GROUP BY press;
\u8bf4\u660e\uff1a
\u8be5\u89c6\u56fe\u4f7f\u7528\u4e86 GROUP BY \u548c COUNT \u805a\u5408\u51fd\u6570\uff0c\u56e0\u6b64\u4e00\u822c\u4e0d\u80fd\u76f4\u63a5\u66f4\u65b0\u3002
6.\u5220\u9664\u89c6\u56fe
DROP VIEW v_unreturned;
DROP VIEW v_student_reader;
DROP VIEW v_press_count;<\/pre>\n\n\n\n12.\u7d22\u5f15<\/h2>\n\n\n\n1.\u521b\u5efa\u666e\u901a\u7d22\u5f15
CREATE INDEX idx_book_bname
ON book(bname);
2.\u521b\u5efa\u552f\u4e00\u7d22\u5f15
CREATE UNIQUE INDEX idx_reader_phone
ON reader(phone);
3.\u521b\u5efa\u590d\u5408\u7d22\u5f15
CREATE INDEX idx_borrow_rno_bno
ON borrow(rno,bno);
\u67e5\u770b\u7d22\u5f15
SHOW INDEX FROM book;
SHOW INDEX FROM reader;
SHOW INDEX FROM borrow;
\u5220\u9664\u7d22\u5f15
DROP INDEX idx_book_bname ON book;
DROP INDEX idx_reader_phone ON reader;
DROP INDEX idx_borrow_rno_bno ON borrow;<\/pre>\n\n\n\n13.\u6570\u636e\u5b8c\u6574\u6027\u7ea6\u675f\u9a8c\u8bc1\u4e0e\u7ea7\u8054\u64cd\u4f5c<\/h2>\n\n\n\n1.\u5b9e\u4f53\u5b8c\u6574\u6027\u9a8c\u8bc1\uff1a\u4e3b\u952e\u4e0d\u80fd\u4e3a\u7a7a
INSERT INTO book(bno,bname,author,press,pubyear,stock)
VALUES(NULL,'\u6d4b\u8bd5\u4e66','\u6d4b\u8bd5\u4f5c\u8005','\u6d4b\u8bd5\u51fa\u7248\u793e',2020,1);
\u8bf4\u660e\uff1a
bno \u662f book \u8868\u4e3b\u952e\uff0c\u4e3b\u952e\u4e0d\u80fd\u4e3a\u7a7a\uff0c\u56e0\u6b64\u63d2\u5165\u5931\u8d25\u3002
2.\u53c2\u7167\u5b8c\u6574\u6027\u9a8c\u8bc1\uff1a\u63d2\u5165\u4e0d\u5b58\u5728\u7684\u56fe\u4e66\u7f16\u53f7
INSERT INTO borrow(rno,bno,borrowdate,returndate,actualdate)
VALUES('R2024001','B999','2025-05-01','2025-05-15',NULL);
\u8bf4\u660e\uff1a
B999 \u5728 book \u8868\u4e2d\u4e0d\u5b58\u5728\uff0cborrow.bno \u662f\u5916\u952e\uff0c\u56e0\u6b64\u8fdd\u53cd\u53c2\u7167\u5b8c\u6574\u6027\u3002
3.\u7528\u6237\u5b9a\u4e49\u5b8c\u6574\u6027\u9a8c\u8bc1\uff1a\u5e93\u5b58\u4e0d\u80fd\u5c0f\u4e8e0
UPDATE book
SET stock = -1
WHERE bno = 'B001';
\u8bf4\u660e\uff1a
stock \u5b57\u6bb5\u8bbe\u7f6e\u4e86 CHECK(stock>=0)\uff0c\u5e93\u5b58\u4e0d\u80fd\u4e3a\u8d1f\u6570\u3002
4.\u7528\u6237\u5b9a\u4e49\u5b8c\u6574\u6027\u9a8c\u8bc1\uff1a\u5e93\u5b58\u4e0d\u80fd\u5c0f\u4e8e0
UPDATE book
SET stock = -1
WHERE bno = 'B001';
\u8bf4\u660e\uff1a
stock \u5b57\u6bb5\u8bbe\u7f6e\u4e86 CHECK(stock>=0)\uff0c\u5e93\u5b58\u4e0d\u80fd\u4e3a\u8d1f\u6570\u3002
5.ON UPDATE CASCADE \u6d4b\u8bd5
UPDATE reader
SET rno = 'R2024999'
WHERE rno = 'R2024003';
SELECT * FROM borrow
WHERE rno = 'R2024999';
\u8bf4\u660e\uff1a
reader.rno \u66f4\u65b0\u540e\uff0cborrow \u8868\u4e2d\u5bf9\u5e94\u7684\u5916\u952e rno \u4f1a\u81ea\u52a8\u540c\u6b65\u66f4\u65b0\u3002<\/pre>\n\n\n\n14.\u89e6\u53d1\u5668<\/h2>\n\n\n\n\u51c6\u5907\uff1a\u5220\u9664\u65e7\u89e6\u53d1\u5668
DROP TRIGGER IF EXISTS trg_borrow_before_insert;
DROP TRIGGER IF EXISTS trg_return_after_update;
DROP TRIGGER IF EXISTS trg_reader_before_delete;
\u521b\u5efa\u5220\u9664\u8bfb\u8005\u65e5\u5fd7\u8868
CREATE TABLE reader_delete_log(
logid INT AUTO_INCREMENT PRIMARY KEY,
rno CHAR(12),
rname VARCHAR(20),
dept VARCHAR(40),
delete_time DATETIME DEFAULT CURRENT_TIMESTAMP
);
1.\u501f\u4e66\u65f6\u81ea\u52a8\u51cf\u5c11\u5e93\u5b58
DELIMITER \/\/
CREATE TRIGGER trg_borrow_before_insert
BEFORE INSERT ON borrow
FOR EACH ROW
BEGIN
DECLARE v_stock INT;
SELECT stock INTO v_stock
FROM book
WHERE bno = NEW.bno;
IF v_stock <= 0 THEN
SIGNAL SQLSTATE '45000'
SET MESSAGE_TEXT = '\u5e93\u5b58\u4e0d\u8db3\uff0c\u4e0d\u80fd\u501f\u4e66';
ELSE
UPDATE book
SET stock = stock - 1
WHERE bno = NEW.bno;
END IF;
END \/\/
DELIMITER ;
\u6d4b\u8bd5\uff1a
SELECT stock FROM book WHERE bno='B003';
INSERT INTO borrow(rno,bno,borrowdate,returndate,actualdate)
VALUES('R2024002','B003','2025-05-01','2025-05-15',NULL);
SELECT stock FROM book WHERE bno='B003';
2.\u8fd8\u4e66\u65f6\u81ea\u52a8\u589e\u52a0\u5e93\u5b58\u5e76\u8ba1\u7b97\u7f5a\u6b3e
DELIMITER \/\/
CREATE TRIGGER trg_return_after_update
AFTER UPDATE ON borrow
FOR EACH ROW
BEGIN
IF OLD.actualdate IS NULL AND NEW.actualdate IS NOT NULL THEN
UPDATE book
SET stock = stock + 1
WHERE bno = NEW.bno;
UPDATE borrow
SET fine =
CASE
WHEN NEW.actualdate > NEW.returndate
THEN DATEDIFF(NEW.actualdate, NEW.returndate) * 1
ELSE 0
END
WHERE borrowid = NEW.borrowid;
END IF;
END \/\/
DELIMITER ;
\u6d4b\u8bd5\uff1a
UPDATE borrow
SET actualdate = '2025-05-18'
WHERE rno='R2024002'
AND bno='B003'
AND borrowdate='2025-05-01';
SELECT * FROM borrow
WHERE rno='R2024002'
AND bno='B003';
SELECT stock FROM book WHERE bno='B003';
3.\u5220\u9664\u8bfb\u8005\u524d\u8bb0\u5f55\u65e5\u5fd7
DELIMITER \/\/
CREATE TRIGGER trg_reader_before_delete
BEFORE DELETE ON reader
FOR EACH ROW
BEGIN
INSERT INTO reader_delete_log(rno,rname,dept)
VALUES(OLD.rno, OLD.rname, OLD.dept);
END \/\/
DELIMITER ;
\u6d4b\u8bd5\uff1a
INSERT INTO reader
VALUES('R2024888','\u65e5\u5fd7\u6d4b\u8bd5','\u7537','\u6d4b\u8bd5\u5b66\u9662','\u65e0');
DELETE FROM reader
WHERE rno='R2024888';
SELECT * FROM reader_delete_log;<\/pre>\n\n\n\n15.\u6570\u636e\u5b89\u5168\u6027<\/h2>\n\n\n\n1.\u521b\u5efa\u7528\u6237\u5e76\u6388\u4e88\u67e5\u8be2\u6743\u9650
CREATE USER 'lib_user1'@'localhost'
IDENTIFIED BY '123456';
GRANT SELECT
ON library_db.book
TO 'lib_user1'@'localhost';
\u67e5\u770b\u6743\u9650\uff1a
SHOW GRANTS FOR 'lib_user1'@'localhost';
2.\u6388\u4e88\u6743\u9650\u5e76\u5141\u8bb8\u8f6c\u6388\u6743
GRANT SELECT, INSERT
ON library_db.reader
TO 'lib_user1'@'localhost'
WITH GRANT OPTION;
\u8bf4\u660e\uff1a
WITH GRANT OPTION \u8868\u793a\u8be5\u7528\u6237\u53ef\u4ee5\u5c06\u81ea\u5df1\u62e5\u6709\u7684\u6743\u9650\u518d\u6388\u4e88\u5176\u4ed6\u7528\u6237\u3002
3.\u56de\u6536\u6743\u9650
REVOKE INSERT
ON library_db.reader
FROM 'lib_user1'@'localhost';
4.\u521b\u5efa\u89d2\u8272\u5e76\u6388\u6743
CREATE ROLE 'reader_role';
GRANT SELECT
ON library_db.*
TO 'reader_role';
CREATE USER 'lib_user2'@'localhost'
IDENTIFIED BY '123456';
GRANT 'reader_role'
TO 'lib_user2'@'localhost';
SET DEFAULT ROLE 'reader_role'
TO 'lib_user2'@'localhost';<\/pre>\n\n\n\n16.\u89c6\u56fe\u4e0e\u6d3e\u751f\u8868<\/h2>\n\n\n\n1.\u5e26\u805a\u5408\u51fd\u6570\u7684\u89c6\u56fe\uff1a\u7edf\u8ba1\u6bcf\u4e2a\u8bfb\u8005\u501f\u9605\u6b21\u6570
CREATE VIEW v_reader_borrow_count AS
SELECT r.rno, r.rname, COUNT(br.borrowid) AS borrow_count
FROM reader r
LEFT JOIN borrow br
ON r.rno = br.rno
GROUP BY r.rno, r.rname;
\u67e5\u8be2\uff1a
SELECT * FROM v_reader_borrow_count;
2.\u6d3e\u751f\u8868\uff1a\u67e5\u8be2\u501f\u9605\u6b21\u6570\u5927\u4e8e1\u7684\u8bfb\u8005
SELECT *
FROM (
SELECT rno, COUNT(*) AS borrow_count
FROM borrow
GROUP BY rno
) AS t
WHERE t.borrow_count > 1;
3.WITH \u5b50\u53e5\u7edf\u8ba1\u6bcf\u4f4d\u8bfb\u8005\u501f\u9605\u6570\u91cf
WITH reader_count AS (
SELECT rno, COUNT(*) AS total
FROM borrow
GROUP BY rno
)
SELECT r.rno, r.rname, rc.total
FROM reader r
LEFT JOIN reader_count rc
ON r.rno = rc.rno;
4.WITH \u5b50\u53e5\uff1a\u67e5\u8be2\u672a\u5f52\u8fd8\u56fe\u4e66
WITH unreturned AS (
SELECT br.borrowid, r.rname, b.bname,
br.borrowdate, br.returndate
FROM borrow br
JOIN reader r ON br.rno = r.rno
JOIN book b ON br.bno = b.bno
WHERE br.actualdate IS NULL
)
SELECT * FROM unreturned;<\/pre>\n\n\n\n17.\u6269\u5c55\u601d\u8003<\/h2>\n\n\n\n\n- \u5982\u4f55\u5904\u7406\u5206\u7c7b\u5b9e\u4f53\u7684\u81ea\u5173\u8054\uff1f<\/li>\n<\/ol>\n\n\n\n
\u5206\u7c7b\u5b9e\u4f53\u5b58\u5728\u201c\u4e0a\u7ea7\u5206\u7c7b\u201d\u548c\u201c\u4e0b\u7ea7\u5206\u7c7b\u201d\u7684\u5173\u7cfb\uff0c\u56e0\u6b64\u53ef\u4ee5\u5728 category \u8868\u4e2d\u8bbe\u7f6e parentid \u5b57\u6bb5\u3002
category(
cid,
cname,
parentid
)
\u5176\u4e2d cid \u662f\u5206\u7c7b\u7f16\u53f7\uff0cparentid \u662f\u4e0a\u7ea7\u5206\u7c7b\u7f16\u53f7\uff0c\u540c\u65f6 parentid \u4e5f\u662f\u6307\u5411 category.cid \u7684\u5916\u952e\u3002
\u5982\u679c\u67d0\u5206\u7c7b\u6ca1\u6709\u4e0a\u7ea7\u5206\u7c7b\uff0c\u5219 parentid \u53ef\u4ee5\u4e3a\u7a7a\u3002
\u8fd9\u79cd\u8bbe\u8ba1\u53ef\u4ee5\u8868\u793a\u6811\u5f62\u7ed3\u6784\uff0c\u4f8b\u5982\uff1a
\u56fe\u4e66
\u251c\u2500\u2500 \u8ba1\u7b97\u673a
\u2502 \u251c\u2500\u2500 \u6570\u636e\u5e93
\u2502 \u2514\u2500\u2500 \u7f51\u7edc\u6280\u672f
\u2514\u2500\u2500 \u6587\u5b66
\u2514\u2500\u2500 \u79d1\u5e7b\u5c0f\u8bf4<\/pre>\n\n\n\n
\n\n\n\n2. \u501f\u9605\u5173\u7cfb\u662f\u5426\u53ef\u80fd\u5b58\u5728\u6570\u636e\u5197\u4f59\uff1f<\/h2>\n\n\n\n\u501f\u9605\u8868\u5982\u679c\u53ea\u4fdd\u5b58 rno\u3001bno\u3001borrowdate\u3001returndate\u3001actualdate \u7b49\u4fe1\u606f\uff0c\u5219\u5197\u4f59\u8f83\u5c11\u3002
\u4f46\u662f\u5982\u679c\u5728 borrow \u8868\u4e2d\u540c\u65f6\u4fdd\u5b58\u8bfb\u8005\u59d3\u540d rname\u3001\u56fe\u4e66\u540d\u79f0 bname\u3001\u51fa\u7248\u793e press \u7b49\u4fe1\u606f\uff0c\u5c31\u4f1a\u4ea7\u751f\u6570\u636e\u5197\u4f59\u3002
\u4f8b\u5982\uff1a
borrow(borrowid, rno, rname, bno, bname, borrowdate)
\u5176\u4e2d rname \u4f9d\u8d56 rno\uff0cbname \u4f9d\u8d56 bno\uff0c\u800c\u4e0d\u662f\u76f4\u63a5\u4f9d\u8d56 borrowid\uff0c\u4f1a\u4ea7\u751f\u4f20\u9012\u4f9d\u8d56\u3002
\u89c4\u8303\u5316\u65b9\u6848\uff1a
\u5c06\u8bfb\u8005\u4fe1\u606f\u4fdd\u5b58\u5728 reader \u8868\uff1b
\u5c06\u56fe\u4e66\u4fe1\u606f\u4fdd\u5b58\u5728 book \u8868\uff1b
borrow \u8868\u53ea\u4fdd\u5b58\u8bfb\u8005\u8bc1\u53f7\u548c\u56fe\u4e66\u7f16\u53f7\u4f5c\u4e3a\u5916\u952e\u3002<\/pre>\n\n\n\n
\n\n\n\n3. \u5982\u4f55\u9632\u6b62\u5e93\u5b58\u4e3a\u8d1f\u6570\uff1f<\/h2>\n\n\n\n\u53ef\u4ee5\u4ece\u4e24\u4e2a\u65b9\u9762\u9632\u6b62\u5e93\u5b58\u4e3a\u8d1f\u6570\uff1a
\u7b2c\u4e00\uff0c\u5728 book \u8868\u4e2d\u8bbe\u7f6e CHECK(stock >= 0) \u7ea6\u675f\uff0c\u4fdd\u8bc1\u5e93\u5b58\u4e0d\u80fd\u5c0f\u4e8e0\u3002
\u7b2c\u4e8c\uff0c\u5728\u501f\u4e66\u89e6\u53d1\u5668\u4e2d\u5224\u65ad\u5e93\u5b58\u6570\u91cf\u3002
\u5f53\u63d2\u5165 borrow \u501f\u9605\u8bb0\u5f55\u65f6\uff0c\u5148\u67e5\u8be2\u56fe\u4e66\u5e93\u5b58\u3002
\u5982\u679c\u5e93\u5b58\u5c0f\u4e8e\u7b49\u4e8e0\uff0c\u5219\u4f7f\u7528 SIGNAL \u629b\u51fa\u9519\u8bef\uff0c\u963b\u6b62\u501f\u4e66\u64cd\u4f5c\uff1b
\u5982\u679c\u5e93\u5b58\u5927\u4e8e0\uff0c\u5219\u5141\u8bb8\u501f\u9605\uff0c\u5e76\u81ea\u52a8\u5c06\u5e93\u5b58\u51cf1\u3002
\u8fd9\u6837\u53ef\u4ee5\u4fdd\u8bc1\u501f\u4e66\u65f6\u4e0d\u4f1a\u51fa\u73b0\u5e93\u5b58\u4e3a\u8d1f\u6570\u7684\u60c5\u51b5\u3002<\/pre>\n\n\n\n
\n\n\n\n4. \u9884\u7ea6\u56fe\u4e66\u529f\u80fd\u9700\u8981\u589e\u52a0\u54ea\u4e9b\u5b9e\u4f53\u548c\u5173\u7cfb\uff1f<\/h2>\n\n\n\n\u5982\u679c\u7cfb\u7edf\u652f\u6301\u9884\u7ea6\u56fe\u4e66\u529f\u80fd\uff0c\u53ef\u4ee5\u589e\u52a0 reservation \u9884\u7ea6\u8868\u3002
reservation(
reserveid,
rno,
bno,
reservedate,
status
)
\u5176\u4e2d\uff1a
reserveid \u8868\u793a\u9884\u7ea6\u7f16\u53f7\uff1b
rno \u662f\u8bfb\u8005\u8bc1\u53f7\uff0c\u5916\u952e\u5f15\u7528 reader.rno\uff1b
bno \u662f\u56fe\u4e66\u7f16\u53f7\uff0c\u5916\u952e\u5f15\u7528 book.bno\uff1b
reservedate \u8868\u793a\u9884\u7ea6\u65e5\u671f\uff1b
status \u8868\u793a\u9884\u7ea6\u72b6\u6001\uff0c\u5982\u201c\u9884\u7ea6\u4e2d\u201d\u201c\u5df2\u53d6\u6d88\u201d\u201c\u5df2\u5b8c\u6210\u201d\u3002
\u65b0\u589e\u5173\u7cfb\uff1a
\u4e00\u4e2a\u8bfb\u8005\u53ef\u4ee5\u9884\u7ea6\u591a\u672c\u56fe\u4e66\uff1b
\u4e00\u672c\u56fe\u4e66\u53ef\u4ee5\u88ab\u591a\u4e2a\u8bfb\u8005\u9884\u7ea6\uff1b
\u8bfb\u8005\u548c\u56fe\u4e66\u4e4b\u95f4\u901a\u8fc7 reservation \u8868\u5f62\u6210 m:n \u8054\u7cfb\u3002<\/pre>\n\n\n\n
\n\n\n\n5. \u4e3a\u4ec0\u4e48\u9075\u5faa\u6700\u5c0f\u6743\u9650\u539f\u5219\uff1f<\/h2>\n\n\n\n\u6700\u5c0f\u6743\u9650\u539f\u5219\u662f\u6307\u53ea\u7ed9\u7528\u6237\u5b8c\u6210\u5de5\u4f5c\u6240\u5fc5\u9700\u7684\u6743\u9650\uff0c\u4e0d\u6388\u4e88\u591a\u4f59\u6743\u9650\u3002
\u5728\u672c\u5b9e\u9a8c\u4e2d\uff0c\u5982\u679c\u67d0\u7528\u6237\u53ea\u8d1f\u8d23\u67e5\u8be2\u56fe\u4e66\u4fe1\u606f\uff0c\u5219\u53ea\u6388\u4e88 SELECT \u6743\u9650\u5373\u53ef\uff0c\u4e0d\u5e94\u8be5\u6388\u4e88 INSERT\u3001UPDATE\u3001DELETE \u7b49\u6743\u9650\u3002
\u4f8b\u5982\uff1a
GRANT SELECT ON library_db.book TO 'lib_user1'@'localhost';
\u8fd9\u6837\u53ef\u4ee5\u9632\u6b62\u7528\u6237\u8bef\u5220\u3001\u8bef\u6539\u6570\u636e\uff0c\u63d0\u9ad8\u6570\u636e\u5e93\u5b89\u5168\u6027\u3002
\u5982\u679c\u540e\u7eed\u4e0d\u518d\u9700\u8981\u67d0\u9879\u6743\u9650\uff0c\u8fd8\u53ef\u4ee5\u4f7f\u7528 REVOKE \u56de\u6536\u6743\u9650\u3002<\/pre>\n\n\n\n
\n\n\n\n6. \u5e76\u53d1\u501f\u9605\u5e93\u5b58\u4ec5\u52691\u672c\u7684\u56fe\u4e66\u4f1a\u4ea7\u751f\u4ec0\u4e48\u95ee\u9898\uff1f\u5982\u4f55\u89e3\u51b3\uff1f<\/h2>\n\n\n\n\u5f53\u591a\u7528\u6237\u540c\u65f6\u501f\u9605\u540c\u4e00\u672c\u5e93\u5b58\u4ec5\u52691\u672c\u7684\u56fe\u4e66\u65f6\uff0c\u53ef\u80fd\u51fa\u73b0\u8d85\u5356\u95ee\u9898\u3002
\u4f8b\u5982\u4e24\u4e2a\u7528\u6237\u540c\u65f6\u8bfb\u53d6\u5e93\u5b58 stock=1\uff0c\u90fd\u8ba4\u4e3a\u53ef\u4ee5\u501f\u9605\uff0c\u7136\u540e\u540c\u65f6\u63d2\u5165\u501f\u9605\u8bb0\u5f55\u5e76\u6267\u884c\u5e93\u5b58\u51cf1\uff0c\u6700\u7ec8\u53ef\u80fd\u5bfc\u81f4\u5e93\u5b58\u5f02\u5e38\u6216\u51fa\u73b0\u8d85\u989d\u501f\u9605\u3002
\u89e3\u51b3\u65b9\u6cd5\uff1a
1. \u4f7f\u7528\u4e8b\u52a1\u4fdd\u8bc1\u501f\u4e66\u64cd\u4f5c\u7684\u539f\u5b50\u6027\uff1b
2. \u4f7f\u7528 SELECT ... FOR UPDATE \u5bf9\u56fe\u4e66\u5e93\u5b58\u8bb0\u5f55\u52a0\u884c\u7ea7\u9501\uff1b
3. \u5728\u89e6\u53d1\u5668\u4e2d\u5224\u65ad\u5e93\u5b58\u662f\u5426\u5927\u4e8e0\uff1b
4. \u7ed9 stock \u5b57\u6bb5\u8bbe\u7f6e CHECK(stock >= 0) \u7ea6\u675f\u3002
\u793a\u4f8b\uff1a
START TRANSACTION;
SELECT stock
FROM book
WHERE bno='B001'
FOR UPDATE;
UPDATE book
SET stock = stock - 1
WHERE bno='B001'
AND stock > 0;
INSERT INTO borrow(rno,bno,borrowdate,returndate)
VALUES('R2024001','B001','2025-05-01','2025-05-15');
COMMIT;
\u8fd9\u6837\u53ef\u4ee5\u907f\u514d\u591a\u4e2a\u7528\u6237\u540c\u65f6\u4fee\u6539\u5e93\u5b58\u5bfc\u81f4\u6570\u636e\u4e0d\u4e00\u81f4\u3002<\/pre>\n\n\n\n
\n\n\n\n\u5b9e\u9a8c\u603b\u7ed3<\/h1>\n\n\n\n \u901a\u8fc7\u672c\u6b21\u56fe\u4e66\u501f\u9605\u7ba1\u7406\u7cfb\u7edf\u7efc\u5408\u5b9e\u9a8c\uff0c\u6211\u7cfb\u7edf\u5730\u5b8c\u6210\u4e86\u6570\u636e\u5e93\u8bbe\u8ba1\u4e0e\u5b9e\u73b0\u7684\u5168\u8fc7\u7a0b\u3002\u5b9e\u9a8c\u4ece\u9700\u6c42\u5206\u6790\u5f00\u59cb\uff0c\u9010\u6b65\u5b8c\u6210 E-R \u56fe\u8bbe\u8ba1\u3001\u5173\u7cfb\u6a21\u5f0f\u8f6c\u6362\u3001\u7269\u7406\u8868\u7ed3\u6784\u8bbe\u8ba1\u3001\u6570\u636e\u63d2\u5165\u3001\u67e5\u8be2\u64cd\u4f5c\u3001\u89c6\u56fe\u3001\u7d22\u5f15\u3001\u5b8c\u6574\u6027\u7ea6\u675f\u3001\u89e6\u53d1\u5668\u548c\u6743\u9650\u7ba1\u7406\u7b49\u5185\u5bb9\uff0c\u4f7f\u6211\u5bf9\u6570\u636e\u5e93\u5e94\u7528\u7cfb\u7edf\u7684\u8bbe\u8ba1\u6d41\u7a0b\u6709\u4e86\u66f4\u52a0\u5b8c\u6574\u7684\u8ba4\u8bc6\u3002
\u200b
\u5728\u5b9e\u9a8c\u8fc7\u7a0b\u4e2d\uff0c\u6211\u9996\u5148\u6839\u636e\u56fe\u4e66\u9986\u4e1a\u52a1\u9700\u6c42\u5206\u6790\u51fa\u56fe\u4e66\u3001\u8bfb\u8005\u3001\u501f\u9605\u3001\u51fa\u7248\u793e\u3001\u5206\u7c7b\u7b49\u5b9e\u4f53\uff0c\u5e76\u660e\u786e\u4e86\u5b83\u4eec\u4e4b\u95f4\u7684\u8054\u7cfb\u7c7b\u578b\u3002\u4f8b\u5982\uff0c\u51fa\u7248\u793e\u4e0e\u56fe\u4e66\u4e4b\u95f4\u662f\u4e00\u5bf9\u591a\u5173\u7cfb\uff0c\u5206\u7c7b\u4e0e\u56fe\u4e66\u4e4b\u95f4\u662f\u4e00\u5bf9\u591a\u5173\u7cfb\uff0c\u8bfb\u8005\u4e0e\u56fe\u4e66\u4e4b\u95f4\u901a\u8fc7\u501f\u9605\u8868\u5f62\u6210\u591a\u5bf9\u591a\u5173\u7cfb\u3002\u901a\u8fc7 E-R \u56fe\u8bbe\u8ba1\uff0c\u6211\u8fdb\u4e00\u6b65\u7406\u89e3\u4e86\u6982\u5ff5\u7ed3\u6784\u8bbe\u8ba1\u5728\u6570\u636e\u5e93\u5f00\u53d1\u4e2d\u7684\u91cd\u8981\u4f5c\u7528\u3002
\u200b
\u5728\u903b\u8f91\u7ed3\u6784\u8bbe\u8ba1\u9636\u6bb5\uff0c\u6211\u5c06 E-R \u56fe\u8f6c\u6362\u4e3a\u5173\u7cfb\u6a21\u5f0f\uff0c\u5e76\u5206\u6790\u5404\u8868\u662f\u5426\u6ee1\u8db3\u7b2c\u4e09\u8303\u5f0f\u3002\u901a\u8fc7\u89c4\u8303\u5316\u8bbe\u8ba1\uff0c\u907f\u514d\u4e86\u5728\u501f\u9605\u8868\u4e2d\u91cd\u590d\u4fdd\u5b58\u8bfb\u8005\u59d3\u540d\u3001\u56fe\u4e66\u540d\u79f0\u7b49\u4fe1\u606f\uff0c\u51cf\u5c11\u4e86\u6570\u636e\u5197\u4f59\uff0c\u63d0\u9ad8\u4e86\u6570\u636e\u4e00\u81f4\u6027\u3002\u5728\u7269\u7406\u8bbe\u8ba1\u9636\u6bb5\uff0c\u6211\u4f7f\u7528 SQL \u521b\u5efa\u6570\u636e\u5e93\u548c\u6570\u636e\u8868\uff0c\u8bbe\u7f6e\u4e86\u4e3b\u952e\u3001\u5916\u952e\u3001\u975e\u7a7a\u3001\u9ed8\u8ba4\u503c\u548c CHECK \u7ea6\u675f\uff0c\u5bf9\u5b9e\u4f53\u5b8c\u6574\u6027\u3001\u53c2\u7167\u5b8c\u6574\u6027\u548c\u7528\u6237\u5b9a\u4e49\u5b8c\u6574\u6027\u6709\u4e86\u66f4\u6df1\u523b\u7684\u7406\u89e3\u3002
\u200b
\u5728\u6570\u636e\u64cd\u4f5c\u90e8\u5206\uff0c\u6211\u7ec3\u4e60\u4e86 INSERT\u3001UPDATE\u3001DELETE \u548c SELECT \u8bed\u53e5\uff0c\u5e76\u5b8c\u6210\u4e86\u57fa\u7840\u67e5\u8be2\u3001\u805a\u5408\u67e5\u8be2\u3001\u591a\u8868\u8fde\u63a5\u67e5\u8be2\u3001\u5d4c\u5957\u67e5\u8be2\u548c\u96c6\u5408\u67e5\u8be2\u7b49\u5185\u5bb9\u3002\u901a\u8fc7\u8fd9\u4e9b\u7ec3\u4e60\uff0c\u6211\u638c\u63e1\u4e86 SQL \u67e5\u8be2\u8bed\u53e5\u7684\u5e38\u89c1\u5199\u6cd5\uff0c\u5c24\u5176\u662f\u591a\u8868\u8fde\u63a5\u548c\u5d4c\u5957\u67e5\u8be2\u7684\u4f7f\u7528\u65b9\u6cd5\u3002\u5b9e\u9a8c\u4e2d\u8fd8\u521b\u5efa\u4e86\u89c6\u56fe\u548c\u7d22\u5f15\uff0c\u7406\u89e3\u4e86\u89c6\u56fe\u53ef\u4ee5\u7b80\u5316\u590d\u6742\u67e5\u8be2\uff0c\u7d22\u5f15\u53ef\u4ee5\u63d0\u9ad8\u67e5\u8be2\u6548\u7387\uff0c\u4f46\u4e5f\u4f1a\u589e\u52a0\u7ef4\u62a4\u6210\u672c\u3002
\u200b
\u5728\u89e6\u53d1\u5668\u90e8\u5206\uff0c\u6211\u5b9e\u73b0\u4e86\u501f\u4e66\u81ea\u52a8\u51cf\u5c11\u5e93\u5b58\u3001\u8fd8\u4e66\u81ea\u52a8\u589e\u52a0\u5e93\u5b58\u5e76\u8ba1\u7b97\u7f5a\u6b3e\u3001\u5220\u9664\u8bfb\u8005\u524d\u8bb0\u5f55\u65e5\u5fd7\u7b49\u529f\u80fd\u3002\u901a\u8fc7\u89e6\u53d1\u5668\u5b9e\u9a8c\uff0c\u6211\u8ba4\u8bc6\u5230\u6570\u636e\u5e93\u4e0d\u4ec5\u53ef\u4ee5\u5b58\u50a8\u6570\u636e\uff0c\u8fd8\u53ef\u4ee5\u5728\u7279\u5b9a\u64cd\u4f5c\u53d1\u751f\u65f6\u81ea\u52a8\u6267\u884c\u4e00\u4e9b\u4e1a\u52a1\u903b\u8f91\u3002\u5b9e\u9a8c\u8fc7\u7a0b\u4e2d\u4e5f\u9047\u5230\u4e86\u4e00\u4e9b\u95ee\u9898\uff0c\u4f8b\u5982\u5916\u952e\u7ea6\u675f\u5bfc\u81f4\u6570\u636e\u65e0\u6cd5\u5220\u9664\u3001CHECK \u7ea6\u675f\u63d2\u5165\u5931\u8d25\u3001\u89e6\u53d1\u5668\u8bed\u6cd5\u9519\u8bef\u7b49\u3002\u901a\u8fc7\u67e5\u770b\u9519\u8bef\u4fe1\u606f\u3001\u4fee\u6539 SQL \u8bed\u53e5\u548c\u53cd\u590d\u6d4b\u8bd5\uff0c\u6700\u7ec8\u89e3\u51b3\u4e86\u8fd9\u4e9b\u95ee\u9898\u3002
\u200b
\u901a\u8fc7\u672c\u6b21\u5b9e\u9a8c\uff0c\u6211\u4e0d\u4ec5\u5de9\u56fa\u4e86\u6570\u636e\u5e93\u7406\u8bba\u77e5\u8bc6\uff0c\u4e5f\u63d0\u9ad8\u4e86 SQL \u7f16\u5199\u80fd\u529b\u548c\u6570\u636e\u5e93\u8c03\u8bd5\u80fd\u529b\u3002\u4eca\u540e\u5728\u8bbe\u8ba1\u6570\u636e\u5e93\u7cfb\u7edf<\/pre>\n","protected":false},"excerpt":{"rendered":"\u6570\u636e\u5e93\u7efc\u5408\u5b9e\u9a8c 1.\u9700\u6c42\u5206\u6790 \u67d0\u5927\u578b\u56fe\u4e66\u9986\u9700\u8981\u5f00\u53d1\u4e00\u5957\u6570\u5b57\u5316\u501f\u9605\u7ba1\u7406\u7cfb\u7edf\uff0c\u4e3b\u8981\u4e1a\u52a1\u9700\u6c42\u5982\u4e0b\uff1a \u56fe\u4e66\u4fe1\u606f\uff1a\u8bb0\u5f55\u56fe […]<\/p>\n","protected":false},"author":1,"featured_media":448,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[9],"tags":[],"class_list":["post-446","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-wenzhang"],"_links":{"self":[{"href":"https:\/\/fg2025.cn\/index.php\/wp-json\/wp\/v2\/posts\/446","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/fg2025.cn\/index.php\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/fg2025.cn\/index.php\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/fg2025.cn\/index.php\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/fg2025.cn\/index.php\/wp-json\/wp\/v2\/comments?post=446"}],"version-history":[{"count":0,"href":"https:\/\/fg2025.cn\/index.php\/wp-json\/wp\/v2\/posts\/446\/revisions"}],"wp:attachment":[{"href":"https:\/\/fg2025.cn\/index.php\/wp-json\/wp\/v2\/media?parent=446"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/fg2025.cn\/index.php\/wp-json\/wp\/v2\/categories?post=446"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/fg2025.cn\/index.php\/wp-json\/wp\/v2\/tags?post=446"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}
UPDATE book
SET stock = 6
WHERE bno = 'B001';
\u200b
SELECT * FROM book WHERE bno='B001';
2.\u4fee\u6539\u5f20\u660e\u7684\u9662\u7cfb\u548c\u7535\u8bdd
UPDATE reader
SET dept = '\u4eba\u5de5\u667a\u80fd\u5b66\u9662',
phone = '18888888888'
WHERE rno = 'R2024001';
\u200b
SELECT * FROM reader WHERE rno='R2024001';
3.\u5c062018\u5e74\u51fa\u7248\u56fe\u4e66\u5e93\u5b58\u7edf\u4e00\u589e\u52a01
UPDATE book
SET stock = stock + 1
WHERE pubyear = 2018;
\u200b
SELECT * FROM book WHERE pubyear=2018;
4.\u5220\u9664\u4e00\u4e2a\u6d4b\u8bd5\u8bfb\u8005
INSERT INTO reader
VALUES('R2024999','\u6d4b\u8bd5\u8bfb\u8005','\u7537','\u6d4b\u8bd5\u5b66\u9662','\u65e0');
\u200b
DELETE FROM reader
WHERE rno = 'R2024999';
5.\u4e8b\u52a1\u63a7\u5236\uff1a\u66f4\u65b0\u540e\u56de\u6eda
START TRANSACTION;
\u200b
UPDATE book
SET stock = stock - 1
WHERE bno = 'B003';
\u200b
SELECT * FROM book WHERE bno='B003';
\u200b
ROLLBACK;
\u200b
SELECT * FROM book WHERE bno='B003';<\/pre>\n\n\n\n
7.\u805a\u5408\u67e5\u8be2\u4e0e\u5206\u7ec4\u7edf\u8ba1<\/h2>\n\n\n\n 1.\u7edf\u8ba1\u56fe\u4e66\u603b\u6570
select count(*) as \u56fe\u4e66\u603b\u6570 from book;
2.\u7edf\u8ba1\u56fe\u4e66\u5e93\u5b58\u603b\u91cf
select sum(stock) as \u5e93\u5b58\u603b\u91cf from book;
3.\u7edf\u8ba1\u5e73\u5747\u5e93\u5b58
select avg(stock) as \u5e73\u5747\u5e93\u5b58 from book;
4.\u67e5\u8be2\u6700\u5927\u5e93\u5b58\u548c\u6700\u5c0f\u5e93\u5b58
SELECT MAX(stock) AS \u6700\u5927\u5e93\u5b58,
MIN(stock) AS \u6700\u5c0f\u5e93\u5b58
FROM book;
5.\u6309\u51fa\u7248\u793e\u7edf\u8ba1\u56fe\u4e66\u6570\u91cf\uff0c\u5e76\u7b5b\u9009\u6570\u91cf\u5927\u4e8e\u7b49\u4e8e1\u7684\u51fa\u7248\u793e
SELECT press, COUNT(*) AS \u56fe\u4e66\u6570\u91cf
FROM book
GROUP BY press
HAVING COUNT(*) >= 1;<\/pre>\n\n\n\n8.\u591a\u8868\u8fde\u63a5\u67e5\u8be2<\/h2>\n\n\n\n1.\u7b49\u503c\u8fde\u63a5\uff1a\u67e5\u8be2\u8bfb\u8005\u59d3\u540d\u548c\u6240\u501f\u56fe\u4e66
SELECT reader.rname, book.bname
FROM reader, borrow, book
WHERE reader.rno = borrow.rno
AND borrow.bno = book.bno;
2.\u5185\u8fde\u63a5\uff1a\u67e5\u8be2\u501f\u9605\u8bb0\u5f55\u8be6\u60c5
SELECT r.rname, b.bname, br.borrowdate, br.returndate
FROM borrow br
JOIN reader r ON br.rno = r.rno
JOIN book b ON br.bno = b.bno;
3.\u5de6\u5916\u8fde\u63a5\uff1a\u67e5\u8be2\u6240\u6709\u8bfb\u8005\u53ca\u5176\u501f\u9605\u8bb0\u5f55
SELECT r.rno, r.rname, br.borrowid, br.bno
FROM reader r
LEFT JOIN borrow br
ON r.rno = br.rno;
4.\u53f3\u5916\u8fde\u63a5\uff1a\u67e5\u8be2\u6240\u6709\u501f\u9605\u8bb0\u5f55\u53ca\u8bfb\u8005\u4fe1\u606f
SELECT r.rname, br.borrowid, br.bno
FROM reader r
RIGHT JOIN borrow br
ON r.rno = br.rno;
5.\u81ea\u8eab\u8fde\u63a5\uff1a\u67e5\u8be2\u540c\u4e00\u5e74\u51fa\u7248\u7684\u4e0d\u540c\u56fe\u4e66
SELECT a.bname AS \u56fe\u4e661,
b.bname AS \u56fe\u4e662,
a.pubyear AS \u51fa\u7248\u5e74\u4efd
FROM book a
JOIN book b
ON a.pubyear = b.pubyear
AND a.bno < b.bno;<\/pre>\n\n\n\n9.\u5d4c\u5957\u67e5\u8be2<\/h2>\n\n\n\n1.IN\uff1a\u67e5\u8be2\u501f\u8fc7\u4e66\u7684\u8bfb\u8005
SELECT *
FROM reader
WHERE rno IN(
SELECT rno FROM borrow
);
2.\u6bd4\u8f83\u8fd0\u7b97\u7b26\uff1a\u67e5\u8be2\u5e93\u5b58\u5927\u4e8e\u5e73\u5747\u5e93\u5b58\u7684\u56fe\u4e66
SELECT bno,bname,stock
FROM book
WHERE stock > (
SELECT AVG(stock)
FROM book
);
3.EXISTS\uff1a\u67e5\u8be2\u5b58\u5728\u501f\u9605\u8bb0\u5f55\u7684\u8bfb\u8005
SELECT *
FROM reader r
WHERE EXISTS(
SELECT *
FROM borrow br
WHERE br.rno = r.rno
);
4.ANY\uff1a\u67e5\u8be2\u5e93\u5b58\u5927\u4e8e\u4efb\u610f\u4e00\u672c2018\u5e74\u51fa\u7248\u56fe\u4e66\u5e93\u5b58\u7684\u56fe\u4e66
SELECT bno,bname,stock
FROM book
WHERE stock > ANY(
SELECT stock
FROM book
WHERE pubyear = 2018
);
5.ALL\uff1a\u67e5\u8be2\u5e93\u5b58\u4e0d\u5c11\u4e8e\u6240\u6709\u56fe\u4e66\u5e93\u5b58\u7684\u56fe\u4e66
SELECT bno,bname,stock
FROM book
WHERE stock >= ALL(
SELECT stock
FROM book
);<\/pre>\n\n\n\n10.\u96c6\u5408\u67e5\u8be2<\/h2>\n\n\n\n1.UNION\uff1a\u5408\u5e76\u8bfb\u8005\u59d3\u540d\u548c\u4f5c\u8005\u59d3\u540d\u5e76\u53bb\u91cd
SELECT rname AS name
FROM reader
UNION
SELECT author AS name
FROM book;
2.UNION ALL\uff1a\u5408\u5e76\u8bfb\u8005\u59d3\u540d\u548c\u4f5c\u8005\u59d3\u540d\uff0c\u4e0d\u53bb\u91cd
SELECT rname AS name
FROM reader
UNION ALL
SELECT author AS name
FROM book;
3.\u6a21\u62df INTERSECT\uff1a\u67e5\u8be2\u501f\u8fc7\u4e66\u7684\u8bfb\u8005\u8bc1\u53f7
SELECT rno
FROM reader
WHERE rno IN(
SELECT rno
FROM borrow
);
4.\u6a21\u62df EXCEPT\uff1a\u67e5\u8be2\u6ca1\u6709\u501f\u4e66\u7684\u8bfb\u8005
SELECT rno,rname
FROM reader
WHERE rno NOT IN(
SELECT rno
FROM borrow
);<\/pre>\n\n\n\n11.\u89c6\u56fe\u64cd\u4f5c<\/h2>\n\n\n\n1.\u521b\u5efa\u672a\u5f52\u8fd8\u56fe\u4e66\u89c6\u56fe
CREATE VIEW v_unreturned AS
SELECT br.borrowid, r.rname, b.bname,
br.borrowdate, br.returndate
FROM borrow br
JOIN reader r ON br.rno = r.rno
JOIN book b ON br.bno = b.bno
WHERE br.actualdate IS NULL;
2.\u67e5\u8be2\u89c6\u56fe
SELECT * FROM v_unreturned;
3.\u521b\u5efa\u5b66\u751f\u8bfb\u8005\u89c6\u56fe\uff0c\u5e26 WITH CHECK OPTION
CREATE VIEW v_student_reader AS
SELECT *
FROM reader
WHERE dept LIKE '%\u5b66\u9662%'
WITH CHECK OPTION;
4.\u6d4b\u8bd5\u53ef\u66f4\u65b0\u89c6\u56fe
UPDATE v_student_reader
SET phone = '18800000000'
WHERE rno = 'R2024002';
\u8bf4\u660e\uff1a
\u8be5\u89c6\u56fe\u57fa\u4e8e\u5355\u8868 reader \u521b\u5efa\uff0c\u6ca1\u6709\u805a\u5408\u51fd\u6570\u3001\u5206\u7ec4\u548c\u8fde\u63a5\uff0c\u56e0\u6b64\u5c5e\u4e8e\u53ef\u66f4\u65b0\u89c6\u56fe\u3002
5.\u521b\u5efa\u4e0d\u53ef\u66f4\u65b0\u7684\u805a\u5408\u89c6\u56fe
CREATE VIEW v_press_count AS
SELECT press, COUNT(*) AS total
FROM book
GROUP BY press;
\u8bf4\u660e\uff1a
\u8be5\u89c6\u56fe\u4f7f\u7528\u4e86 GROUP BY \u548c COUNT \u805a\u5408\u51fd\u6570\uff0c\u56e0\u6b64\u4e00\u822c\u4e0d\u80fd\u76f4\u63a5\u66f4\u65b0\u3002
6.\u5220\u9664\u89c6\u56fe
DROP VIEW v_unreturned;
DROP VIEW v_student_reader;
DROP VIEW v_press_count;<\/pre>\n\n\n\n12.\u7d22\u5f15<\/h2>\n\n\n\n1.\u521b\u5efa\u666e\u901a\u7d22\u5f15
CREATE INDEX idx_book_bname
ON book(bname);
2.\u521b\u5efa\u552f\u4e00\u7d22\u5f15
CREATE UNIQUE INDEX idx_reader_phone
ON reader(phone);
3.\u521b\u5efa\u590d\u5408\u7d22\u5f15
CREATE INDEX idx_borrow_rno_bno
ON borrow(rno,bno);
\u67e5\u770b\u7d22\u5f15
SHOW INDEX FROM book;
SHOW INDEX FROM reader;
SHOW INDEX FROM borrow;
\u5220\u9664\u7d22\u5f15
DROP INDEX idx_book_bname ON book;
DROP INDEX idx_reader_phone ON reader;
DROP INDEX idx_borrow_rno_bno ON borrow;<\/pre>\n\n\n\n13.\u6570\u636e\u5b8c\u6574\u6027\u7ea6\u675f\u9a8c\u8bc1\u4e0e\u7ea7\u8054\u64cd\u4f5c<\/h2>\n\n\n\n1.\u5b9e\u4f53\u5b8c\u6574\u6027\u9a8c\u8bc1\uff1a\u4e3b\u952e\u4e0d\u80fd\u4e3a\u7a7a
INSERT INTO book(bno,bname,author,press,pubyear,stock)
VALUES(NULL,'\u6d4b\u8bd5\u4e66','\u6d4b\u8bd5\u4f5c\u8005','\u6d4b\u8bd5\u51fa\u7248\u793e',2020,1);
\u8bf4\u660e\uff1a
bno \u662f book \u8868\u4e3b\u952e\uff0c\u4e3b\u952e\u4e0d\u80fd\u4e3a\u7a7a\uff0c\u56e0\u6b64\u63d2\u5165\u5931\u8d25\u3002
2.\u53c2\u7167\u5b8c\u6574\u6027\u9a8c\u8bc1\uff1a\u63d2\u5165\u4e0d\u5b58\u5728\u7684\u56fe\u4e66\u7f16\u53f7
INSERT INTO borrow(rno,bno,borrowdate,returndate,actualdate)
VALUES('R2024001','B999','2025-05-01','2025-05-15',NULL);
\u8bf4\u660e\uff1a
B999 \u5728 book \u8868\u4e2d\u4e0d\u5b58\u5728\uff0cborrow.bno \u662f\u5916\u952e\uff0c\u56e0\u6b64\u8fdd\u53cd\u53c2\u7167\u5b8c\u6574\u6027\u3002
3.\u7528\u6237\u5b9a\u4e49\u5b8c\u6574\u6027\u9a8c\u8bc1\uff1a\u5e93\u5b58\u4e0d\u80fd\u5c0f\u4e8e0
UPDATE book
SET stock = -1
WHERE bno = 'B001';
\u8bf4\u660e\uff1a
stock \u5b57\u6bb5\u8bbe\u7f6e\u4e86 CHECK(stock>=0)\uff0c\u5e93\u5b58\u4e0d\u80fd\u4e3a\u8d1f\u6570\u3002
4.\u7528\u6237\u5b9a\u4e49\u5b8c\u6574\u6027\u9a8c\u8bc1\uff1a\u5e93\u5b58\u4e0d\u80fd\u5c0f\u4e8e0
UPDATE book
SET stock = -1
WHERE bno = 'B001';
\u8bf4\u660e\uff1a
stock \u5b57\u6bb5\u8bbe\u7f6e\u4e86 CHECK(stock>=0)\uff0c\u5e93\u5b58\u4e0d\u80fd\u4e3a\u8d1f\u6570\u3002
5.ON UPDATE CASCADE \u6d4b\u8bd5
UPDATE reader
SET rno = 'R2024999'
WHERE rno = 'R2024003';
SELECT * FROM borrow
WHERE rno = 'R2024999';
\u8bf4\u660e\uff1a
reader.rno \u66f4\u65b0\u540e\uff0cborrow \u8868\u4e2d\u5bf9\u5e94\u7684\u5916\u952e rno \u4f1a\u81ea\u52a8\u540c\u6b65\u66f4\u65b0\u3002<\/pre>\n\n\n\n14.\u89e6\u53d1\u5668<\/h2>\n\n\n\n\u51c6\u5907\uff1a\u5220\u9664\u65e7\u89e6\u53d1\u5668
DROP TRIGGER IF EXISTS trg_borrow_before_insert;
DROP TRIGGER IF EXISTS trg_return_after_update;
DROP TRIGGER IF EXISTS trg_reader_before_delete;
\u521b\u5efa\u5220\u9664\u8bfb\u8005\u65e5\u5fd7\u8868
CREATE TABLE reader_delete_log(
logid INT AUTO_INCREMENT PRIMARY KEY,
rno CHAR(12),
rname VARCHAR(20),
dept VARCHAR(40),
delete_time DATETIME DEFAULT CURRENT_TIMESTAMP
);
1.\u501f\u4e66\u65f6\u81ea\u52a8\u51cf\u5c11\u5e93\u5b58
DELIMITER \/\/
CREATE TRIGGER trg_borrow_before_insert
BEFORE INSERT ON borrow
FOR EACH ROW
BEGIN
DECLARE v_stock INT;
SELECT stock INTO v_stock
FROM book
WHERE bno = NEW.bno;
IF v_stock <= 0 THEN
SIGNAL SQLSTATE '45000'
SET MESSAGE_TEXT = '\u5e93\u5b58\u4e0d\u8db3\uff0c\u4e0d\u80fd\u501f\u4e66';
ELSE
UPDATE book
SET stock = stock - 1
WHERE bno = NEW.bno;
END IF;
END \/\/
DELIMITER ;
\u6d4b\u8bd5\uff1a
SELECT stock FROM book WHERE bno='B003';
INSERT INTO borrow(rno,bno,borrowdate,returndate,actualdate)
VALUES('R2024002','B003','2025-05-01','2025-05-15',NULL);
SELECT stock FROM book WHERE bno='B003';
2.\u8fd8\u4e66\u65f6\u81ea\u52a8\u589e\u52a0\u5e93\u5b58\u5e76\u8ba1\u7b97\u7f5a\u6b3e
DELIMITER \/\/
CREATE TRIGGER trg_return_after_update
AFTER UPDATE ON borrow
FOR EACH ROW
BEGIN
IF OLD.actualdate IS NULL AND NEW.actualdate IS NOT NULL THEN
UPDATE book
SET stock = stock + 1
WHERE bno = NEW.bno;
UPDATE borrow
SET fine =
CASE
WHEN NEW.actualdate > NEW.returndate
THEN DATEDIFF(NEW.actualdate, NEW.returndate) * 1
ELSE 0
END
WHERE borrowid = NEW.borrowid;
END IF;
END \/\/
DELIMITER ;
\u6d4b\u8bd5\uff1a
UPDATE borrow
SET actualdate = '2025-05-18'
WHERE rno='R2024002'
AND bno='B003'
AND borrowdate='2025-05-01';
SELECT * FROM borrow
WHERE rno='R2024002'
AND bno='B003';
SELECT stock FROM book WHERE bno='B003';
3.\u5220\u9664\u8bfb\u8005\u524d\u8bb0\u5f55\u65e5\u5fd7
DELIMITER \/\/
CREATE TRIGGER trg_reader_before_delete
BEFORE DELETE ON reader
FOR EACH ROW
BEGIN
INSERT INTO reader_delete_log(rno,rname,dept)
VALUES(OLD.rno, OLD.rname, OLD.dept);
END \/\/
DELIMITER ;
\u6d4b\u8bd5\uff1a
INSERT INTO reader
VALUES('R2024888','\u65e5\u5fd7\u6d4b\u8bd5','\u7537','\u6d4b\u8bd5\u5b66\u9662','\u65e0');
DELETE FROM reader
WHERE rno='R2024888';
SELECT * FROM reader_delete_log;<\/pre>\n\n\n\n15.\u6570\u636e\u5b89\u5168\u6027<\/h2>\n\n\n\n1.\u521b\u5efa\u7528\u6237\u5e76\u6388\u4e88\u67e5\u8be2\u6743\u9650
CREATE USER 'lib_user1'@'localhost'
IDENTIFIED BY '123456';
GRANT SELECT
ON library_db.book
TO 'lib_user1'@'localhost';
\u67e5\u770b\u6743\u9650\uff1a
SHOW GRANTS FOR 'lib_user1'@'localhost';
2.\u6388\u4e88\u6743\u9650\u5e76\u5141\u8bb8\u8f6c\u6388\u6743
GRANT SELECT, INSERT
ON library_db.reader
TO 'lib_user1'@'localhost'
WITH GRANT OPTION;
\u8bf4\u660e\uff1a
WITH GRANT OPTION \u8868\u793a\u8be5\u7528\u6237\u53ef\u4ee5\u5c06\u81ea\u5df1\u62e5\u6709\u7684\u6743\u9650\u518d\u6388\u4e88\u5176\u4ed6\u7528\u6237\u3002
3.\u56de\u6536\u6743\u9650
REVOKE INSERT
ON library_db.reader
FROM 'lib_user1'@'localhost';
4.\u521b\u5efa\u89d2\u8272\u5e76\u6388\u6743
CREATE ROLE 'reader_role';
GRANT SELECT
ON library_db.*
TO 'reader_role';
CREATE USER 'lib_user2'@'localhost'
IDENTIFIED BY '123456';
GRANT 'reader_role'
TO 'lib_user2'@'localhost';
SET DEFAULT ROLE 'reader_role'
TO 'lib_user2'@'localhost';<\/pre>\n\n\n\n16.\u89c6\u56fe\u4e0e\u6d3e\u751f\u8868<\/h2>\n\n\n\n1.\u5e26\u805a\u5408\u51fd\u6570\u7684\u89c6\u56fe\uff1a\u7edf\u8ba1\u6bcf\u4e2a\u8bfb\u8005\u501f\u9605\u6b21\u6570
CREATE VIEW v_reader_borrow_count AS
SELECT r.rno, r.rname, COUNT(br.borrowid) AS borrow_count
FROM reader r
LEFT JOIN borrow br
ON r.rno = br.rno
GROUP BY r.rno, r.rname;
\u67e5\u8be2\uff1a
SELECT * FROM v_reader_borrow_count;
2.\u6d3e\u751f\u8868\uff1a\u67e5\u8be2\u501f\u9605\u6b21\u6570\u5927\u4e8e1\u7684\u8bfb\u8005
SELECT *
FROM (
SELECT rno, COUNT(*) AS borrow_count
FROM borrow
GROUP BY rno
) AS t
WHERE t.borrow_count > 1;
3.WITH \u5b50\u53e5\u7edf\u8ba1\u6bcf\u4f4d\u8bfb\u8005\u501f\u9605\u6570\u91cf
WITH reader_count AS (
SELECT rno, COUNT(*) AS total
FROM borrow
GROUP BY rno
)
SELECT r.rno, r.rname, rc.total
FROM reader r
LEFT JOIN reader_count rc
ON r.rno = rc.rno;
4.WITH \u5b50\u53e5\uff1a\u67e5\u8be2\u672a\u5f52\u8fd8\u56fe\u4e66
WITH unreturned AS (
SELECT br.borrowid, r.rname, b.bname,
br.borrowdate, br.returndate
FROM borrow br
JOIN reader r ON br.rno = r.rno
JOIN book b ON br.bno = b.bno
WHERE br.actualdate IS NULL
)
SELECT * FROM unreturned;<\/pre>\n\n\n\n17.\u6269\u5c55\u601d\u8003<\/h2>\n\n\n\n\n- \u5982\u4f55\u5904\u7406\u5206\u7c7b\u5b9e\u4f53\u7684\u81ea\u5173\u8054\uff1f<\/li>\n<\/ol>\n\n\n\n
\u5206\u7c7b\u5b9e\u4f53\u5b58\u5728\u201c\u4e0a\u7ea7\u5206\u7c7b\u201d\u548c\u201c\u4e0b\u7ea7\u5206\u7c7b\u201d\u7684\u5173\u7cfb\uff0c\u56e0\u6b64\u53ef\u4ee5\u5728 category \u8868\u4e2d\u8bbe\u7f6e parentid \u5b57\u6bb5\u3002
category(
cid,
cname,
parentid
)
\u5176\u4e2d cid \u662f\u5206\u7c7b\u7f16\u53f7\uff0cparentid \u662f\u4e0a\u7ea7\u5206\u7c7b\u7f16\u53f7\uff0c\u540c\u65f6 parentid \u4e5f\u662f\u6307\u5411 category.cid \u7684\u5916\u952e\u3002
\u5982\u679c\u67d0\u5206\u7c7b\u6ca1\u6709\u4e0a\u7ea7\u5206\u7c7b\uff0c\u5219 parentid \u53ef\u4ee5\u4e3a\u7a7a\u3002
\u8fd9\u79cd\u8bbe\u8ba1\u53ef\u4ee5\u8868\u793a\u6811\u5f62\u7ed3\u6784\uff0c\u4f8b\u5982\uff1a
\u56fe\u4e66
\u251c\u2500\u2500 \u8ba1\u7b97\u673a
\u2502 \u251c\u2500\u2500 \u6570\u636e\u5e93
\u2502 \u2514\u2500\u2500 \u7f51\u7edc\u6280\u672f
\u2514\u2500\u2500 \u6587\u5b66
\u2514\u2500\u2500 \u79d1\u5e7b\u5c0f\u8bf4<\/pre>\n\n\n\n
\n\n\n\n2. \u501f\u9605\u5173\u7cfb\u662f\u5426\u53ef\u80fd\u5b58\u5728\u6570\u636e\u5197\u4f59\uff1f<\/h2>\n\n\n\n\u501f\u9605\u8868\u5982\u679c\u53ea\u4fdd\u5b58 rno\u3001bno\u3001borrowdate\u3001returndate\u3001actualdate \u7b49\u4fe1\u606f\uff0c\u5219\u5197\u4f59\u8f83\u5c11\u3002
\u4f46\u662f\u5982\u679c\u5728 borrow \u8868\u4e2d\u540c\u65f6\u4fdd\u5b58\u8bfb\u8005\u59d3\u540d rname\u3001\u56fe\u4e66\u540d\u79f0 bname\u3001\u51fa\u7248\u793e press \u7b49\u4fe1\u606f\uff0c\u5c31\u4f1a\u4ea7\u751f\u6570\u636e\u5197\u4f59\u3002
\u4f8b\u5982\uff1a
borrow(borrowid, rno, rname, bno, bname, borrowdate)
\u5176\u4e2d rname \u4f9d\u8d56 rno\uff0cbname \u4f9d\u8d56 bno\uff0c\u800c\u4e0d\u662f\u76f4\u63a5\u4f9d\u8d56 borrowid\uff0c\u4f1a\u4ea7\u751f\u4f20\u9012\u4f9d\u8d56\u3002
\u89c4\u8303\u5316\u65b9\u6848\uff1a
\u5c06\u8bfb\u8005\u4fe1\u606f\u4fdd\u5b58\u5728 reader \u8868\uff1b
\u5c06\u56fe\u4e66\u4fe1\u606f\u4fdd\u5b58\u5728 book \u8868\uff1b
borrow \u8868\u53ea\u4fdd\u5b58\u8bfb\u8005\u8bc1\u53f7\u548c\u56fe\u4e66\u7f16\u53f7\u4f5c\u4e3a\u5916\u952e\u3002<\/pre>\n\n\n\n
\n\n\n\n3. \u5982\u4f55\u9632\u6b62\u5e93\u5b58\u4e3a\u8d1f\u6570\uff1f<\/h2>\n\n\n\n\u53ef\u4ee5\u4ece\u4e24\u4e2a\u65b9\u9762\u9632\u6b62\u5e93\u5b58\u4e3a\u8d1f\u6570\uff1a
\u7b2c\u4e00\uff0c\u5728 book \u8868\u4e2d\u8bbe\u7f6e CHECK(stock >= 0) \u7ea6\u675f\uff0c\u4fdd\u8bc1\u5e93\u5b58\u4e0d\u80fd\u5c0f\u4e8e0\u3002
\u7b2c\u4e8c\uff0c\u5728\u501f\u4e66\u89e6\u53d1\u5668\u4e2d\u5224\u65ad\u5e93\u5b58\u6570\u91cf\u3002
\u5f53\u63d2\u5165 borrow \u501f\u9605\u8bb0\u5f55\u65f6\uff0c\u5148\u67e5\u8be2\u56fe\u4e66\u5e93\u5b58\u3002
\u5982\u679c\u5e93\u5b58\u5c0f\u4e8e\u7b49\u4e8e0\uff0c\u5219\u4f7f\u7528 SIGNAL \u629b\u51fa\u9519\u8bef\uff0c\u963b\u6b62\u501f\u4e66\u64cd\u4f5c\uff1b
\u5982\u679c\u5e93\u5b58\u5927\u4e8e0\uff0c\u5219\u5141\u8bb8\u501f\u9605\uff0c\u5e76\u81ea\u52a8\u5c06\u5e93\u5b58\u51cf1\u3002
\u8fd9\u6837\u53ef\u4ee5\u4fdd\u8bc1\u501f\u4e66\u65f6\u4e0d\u4f1a\u51fa\u73b0\u5e93\u5b58\u4e3a\u8d1f\u6570\u7684\u60c5\u51b5\u3002<\/pre>\n\n\n\n
\n\n\n\n4. \u9884\u7ea6\u56fe\u4e66\u529f\u80fd\u9700\u8981\u589e\u52a0\u54ea\u4e9b\u5b9e\u4f53\u548c\u5173\u7cfb\uff1f<\/h2>\n\n\n\n\u5982\u679c\u7cfb\u7edf\u652f\u6301\u9884\u7ea6\u56fe\u4e66\u529f\u80fd\uff0c\u53ef\u4ee5\u589e\u52a0 reservation \u9884\u7ea6\u8868\u3002
reservation(
reserveid,
rno,
bno,
reservedate,
status
)
\u5176\u4e2d\uff1a
reserveid \u8868\u793a\u9884\u7ea6\u7f16\u53f7\uff1b
rno \u662f\u8bfb\u8005\u8bc1\u53f7\uff0c\u5916\u952e\u5f15\u7528 reader.rno\uff1b
bno \u662f\u56fe\u4e66\u7f16\u53f7\uff0c\u5916\u952e\u5f15\u7528 book.bno\uff1b
reservedate \u8868\u793a\u9884\u7ea6\u65e5\u671f\uff1b
status \u8868\u793a\u9884\u7ea6\u72b6\u6001\uff0c\u5982\u201c\u9884\u7ea6\u4e2d\u201d\u201c\u5df2\u53d6\u6d88\u201d\u201c\u5df2\u5b8c\u6210\u201d\u3002
\u65b0\u589e\u5173\u7cfb\uff1a
\u4e00\u4e2a\u8bfb\u8005\u53ef\u4ee5\u9884\u7ea6\u591a\u672c\u56fe\u4e66\uff1b
\u4e00\u672c\u56fe\u4e66\u53ef\u4ee5\u88ab\u591a\u4e2a\u8bfb\u8005\u9884\u7ea6\uff1b
\u8bfb\u8005\u548c\u56fe\u4e66\u4e4b\u95f4\u901a\u8fc7 reservation \u8868\u5f62\u6210 m:n \u8054\u7cfb\u3002<\/pre>\n\n\n\n
\n\n\n\n5. \u4e3a\u4ec0\u4e48\u9075\u5faa\u6700\u5c0f\u6743\u9650\u539f\u5219\uff1f<\/h2>\n\n\n\n\u6700\u5c0f\u6743\u9650\u539f\u5219\u662f\u6307\u53ea\u7ed9\u7528\u6237\u5b8c\u6210\u5de5\u4f5c\u6240\u5fc5\u9700\u7684\u6743\u9650\uff0c\u4e0d\u6388\u4e88\u591a\u4f59\u6743\u9650\u3002
\u5728\u672c\u5b9e\u9a8c\u4e2d\uff0c\u5982\u679c\u67d0\u7528\u6237\u53ea\u8d1f\u8d23\u67e5\u8be2\u56fe\u4e66\u4fe1\u606f\uff0c\u5219\u53ea\u6388\u4e88 SELECT \u6743\u9650\u5373\u53ef\uff0c\u4e0d\u5e94\u8be5\u6388\u4e88 INSERT\u3001UPDATE\u3001DELETE \u7b49\u6743\u9650\u3002
\u4f8b\u5982\uff1a
GRANT SELECT ON library_db.book TO 'lib_user1'@'localhost';
\u8fd9\u6837\u53ef\u4ee5\u9632\u6b62\u7528\u6237\u8bef\u5220\u3001\u8bef\u6539\u6570\u636e\uff0c\u63d0\u9ad8\u6570\u636e\u5e93\u5b89\u5168\u6027\u3002
\u5982\u679c\u540e\u7eed\u4e0d\u518d\u9700\u8981\u67d0\u9879\u6743\u9650\uff0c\u8fd8\u53ef\u4ee5\u4f7f\u7528 REVOKE \u56de\u6536\u6743\u9650\u3002<\/pre>\n\n\n\n
\n\n\n\n6. \u5e76\u53d1\u501f\u9605\u5e93\u5b58\u4ec5\u52691\u672c\u7684\u56fe\u4e66\u4f1a\u4ea7\u751f\u4ec0\u4e48\u95ee\u9898\uff1f\u5982\u4f55\u89e3\u51b3\uff1f<\/h2>\n\n\n\n\u5f53\u591a\u7528\u6237\u540c\u65f6\u501f\u9605\u540c\u4e00\u672c\u5e93\u5b58\u4ec5\u52691\u672c\u7684\u56fe\u4e66\u65f6\uff0c\u53ef\u80fd\u51fa\u73b0\u8d85\u5356\u95ee\u9898\u3002
\u4f8b\u5982\u4e24\u4e2a\u7528\u6237\u540c\u65f6\u8bfb\u53d6\u5e93\u5b58 stock=1\uff0c\u90fd\u8ba4\u4e3a\u53ef\u4ee5\u501f\u9605\uff0c\u7136\u540e\u540c\u65f6\u63d2\u5165\u501f\u9605\u8bb0\u5f55\u5e76\u6267\u884c\u5e93\u5b58\u51cf1\uff0c\u6700\u7ec8\u53ef\u80fd\u5bfc\u81f4\u5e93\u5b58\u5f02\u5e38\u6216\u51fa\u73b0\u8d85\u989d\u501f\u9605\u3002
\u89e3\u51b3\u65b9\u6cd5\uff1a
1. \u4f7f\u7528\u4e8b\u52a1\u4fdd\u8bc1\u501f\u4e66\u64cd\u4f5c\u7684\u539f\u5b50\u6027\uff1b
2. \u4f7f\u7528 SELECT ... FOR UPDATE \u5bf9\u56fe\u4e66\u5e93\u5b58\u8bb0\u5f55\u52a0\u884c\u7ea7\u9501\uff1b
3. \u5728\u89e6\u53d1\u5668\u4e2d\u5224\u65ad\u5e93\u5b58\u662f\u5426\u5927\u4e8e0\uff1b
4. \u7ed9 stock \u5b57\u6bb5\u8bbe\u7f6e CHECK(stock >= 0) \u7ea6\u675f\u3002
\u793a\u4f8b\uff1a
START TRANSACTION;
SELECT stock
FROM book
WHERE bno='B001'
FOR UPDATE;
UPDATE book
SET stock = stock - 1
WHERE bno='B001'
AND stock > 0;
INSERT INTO borrow(rno,bno,borrowdate,returndate)
VALUES('R2024001','B001','2025-05-01','2025-05-15');
COMMIT;
\u8fd9\u6837\u53ef\u4ee5\u907f\u514d\u591a\u4e2a\u7528\u6237\u540c\u65f6\u4fee\u6539\u5e93\u5b58\u5bfc\u81f4\u6570\u636e\u4e0d\u4e00\u81f4\u3002<\/pre>\n\n\n\n
\n\n\n\n\u5b9e\u9a8c\u603b\u7ed3<\/h1>\n\n\n\n \u901a\u8fc7\u672c\u6b21\u56fe\u4e66\u501f\u9605\u7ba1\u7406\u7cfb\u7edf\u7efc\u5408\u5b9e\u9a8c\uff0c\u6211\u7cfb\u7edf\u5730\u5b8c\u6210\u4e86\u6570\u636e\u5e93\u8bbe\u8ba1\u4e0e\u5b9e\u73b0\u7684\u5168\u8fc7\u7a0b\u3002\u5b9e\u9a8c\u4ece\u9700\u6c42\u5206\u6790\u5f00\u59cb\uff0c\u9010\u6b65\u5b8c\u6210 E-R \u56fe\u8bbe\u8ba1\u3001\u5173\u7cfb\u6a21\u5f0f\u8f6c\u6362\u3001\u7269\u7406\u8868\u7ed3\u6784\u8bbe\u8ba1\u3001\u6570\u636e\u63d2\u5165\u3001\u67e5\u8be2\u64cd\u4f5c\u3001\u89c6\u56fe\u3001\u7d22\u5f15\u3001\u5b8c\u6574\u6027\u7ea6\u675f\u3001\u89e6\u53d1\u5668\u548c\u6743\u9650\u7ba1\u7406\u7b49\u5185\u5bb9\uff0c\u4f7f\u6211\u5bf9\u6570\u636e\u5e93\u5e94\u7528\u7cfb\u7edf\u7684\u8bbe\u8ba1\u6d41\u7a0b\u6709\u4e86\u66f4\u52a0\u5b8c\u6574\u7684\u8ba4\u8bc6\u3002
\u200b
\u5728\u5b9e\u9a8c\u8fc7\u7a0b\u4e2d\uff0c\u6211\u9996\u5148\u6839\u636e\u56fe\u4e66\u9986\u4e1a\u52a1\u9700\u6c42\u5206\u6790\u51fa\u56fe\u4e66\u3001\u8bfb\u8005\u3001\u501f\u9605\u3001\u51fa\u7248\u793e\u3001\u5206\u7c7b\u7b49\u5b9e\u4f53\uff0c\u5e76\u660e\u786e\u4e86\u5b83\u4eec\u4e4b\u95f4\u7684\u8054\u7cfb\u7c7b\u578b\u3002\u4f8b\u5982\uff0c\u51fa\u7248\u793e\u4e0e\u56fe\u4e66\u4e4b\u95f4\u662f\u4e00\u5bf9\u591a\u5173\u7cfb\uff0c\u5206\u7c7b\u4e0e\u56fe\u4e66\u4e4b\u95f4\u662f\u4e00\u5bf9\u591a\u5173\u7cfb\uff0c\u8bfb\u8005\u4e0e\u56fe\u4e66\u4e4b\u95f4\u901a\u8fc7\u501f\u9605\u8868\u5f62\u6210\u591a\u5bf9\u591a\u5173\u7cfb\u3002\u901a\u8fc7 E-R \u56fe\u8bbe\u8ba1\uff0c\u6211\u8fdb\u4e00\u6b65\u7406\u89e3\u4e86\u6982\u5ff5\u7ed3\u6784\u8bbe\u8ba1\u5728\u6570\u636e\u5e93\u5f00\u53d1\u4e2d\u7684\u91cd\u8981\u4f5c\u7528\u3002
\u200b
\u5728\u903b\u8f91\u7ed3\u6784\u8bbe\u8ba1\u9636\u6bb5\uff0c\u6211\u5c06 E-R \u56fe\u8f6c\u6362\u4e3a\u5173\u7cfb\u6a21\u5f0f\uff0c\u5e76\u5206\u6790\u5404\u8868\u662f\u5426\u6ee1\u8db3\u7b2c\u4e09\u8303\u5f0f\u3002\u901a\u8fc7\u89c4\u8303\u5316\u8bbe\u8ba1\uff0c\u907f\u514d\u4e86\u5728\u501f\u9605\u8868\u4e2d\u91cd\u590d\u4fdd\u5b58\u8bfb\u8005\u59d3\u540d\u3001\u56fe\u4e66\u540d\u79f0\u7b49\u4fe1\u606f\uff0c\u51cf\u5c11\u4e86\u6570\u636e\u5197\u4f59\uff0c\u63d0\u9ad8\u4e86\u6570\u636e\u4e00\u81f4\u6027\u3002\u5728\u7269\u7406\u8bbe\u8ba1\u9636\u6bb5\uff0c\u6211\u4f7f\u7528 SQL \u521b\u5efa\u6570\u636e\u5e93\u548c\u6570\u636e\u8868\uff0c\u8bbe\u7f6e\u4e86\u4e3b\u952e\u3001\u5916\u952e\u3001\u975e\u7a7a\u3001\u9ed8\u8ba4\u503c\u548c CHECK \u7ea6\u675f\uff0c\u5bf9\u5b9e\u4f53\u5b8c\u6574\u6027\u3001\u53c2\u7167\u5b8c\u6574\u6027\u548c\u7528\u6237\u5b9a\u4e49\u5b8c\u6574\u6027\u6709\u4e86\u66f4\u6df1\u523b\u7684\u7406\u89e3\u3002
\u200b
\u5728\u6570\u636e\u64cd\u4f5c\u90e8\u5206\uff0c\u6211\u7ec3\u4e60\u4e86 INSERT\u3001UPDATE\u3001DELETE \u548c SELECT \u8bed\u53e5\uff0c\u5e76\u5b8c\u6210\u4e86\u57fa\u7840\u67e5\u8be2\u3001\u805a\u5408\u67e5\u8be2\u3001\u591a\u8868\u8fde\u63a5\u67e5\u8be2\u3001\u5d4c\u5957\u67e5\u8be2\u548c\u96c6\u5408\u67e5\u8be2\u7b49\u5185\u5bb9\u3002\u901a\u8fc7\u8fd9\u4e9b\u7ec3\u4e60\uff0c\u6211\u638c\u63e1\u4e86 SQL \u67e5\u8be2\u8bed\u53e5\u7684\u5e38\u89c1\u5199\u6cd5\uff0c\u5c24\u5176\u662f\u591a\u8868\u8fde\u63a5\u548c\u5d4c\u5957\u67e5\u8be2\u7684\u4f7f\u7528\u65b9\u6cd5\u3002\u5b9e\u9a8c\u4e2d\u8fd8\u521b\u5efa\u4e86\u89c6\u56fe\u548c\u7d22\u5f15\uff0c\u7406\u89e3\u4e86\u89c6\u56fe\u53ef\u4ee5\u7b80\u5316\u590d\u6742\u67e5\u8be2\uff0c\u7d22\u5f15\u53ef\u4ee5\u63d0\u9ad8\u67e5\u8be2\u6548\u7387\uff0c\u4f46\u4e5f\u4f1a\u589e\u52a0\u7ef4\u62a4\u6210\u672c\u3002
\u200b
\u5728\u89e6\u53d1\u5668\u90e8\u5206\uff0c\u6211\u5b9e\u73b0\u4e86\u501f\u4e66\u81ea\u52a8\u51cf\u5c11\u5e93\u5b58\u3001\u8fd8\u4e66\u81ea\u52a8\u589e\u52a0\u5e93\u5b58\u5e76\u8ba1\u7b97\u7f5a\u6b3e\u3001\u5220\u9664\u8bfb\u8005\u524d\u8bb0\u5f55\u65e5\u5fd7\u7b49\u529f\u80fd\u3002\u901a\u8fc7\u89e6\u53d1\u5668\u5b9e\u9a8c\uff0c\u6211\u8ba4\u8bc6\u5230\u6570\u636e\u5e93\u4e0d\u4ec5\u53ef\u4ee5\u5b58\u50a8\u6570\u636e\uff0c\u8fd8\u53ef\u4ee5\u5728\u7279\u5b9a\u64cd\u4f5c\u53d1\u751f\u65f6\u81ea\u52a8\u6267\u884c\u4e00\u4e9b\u4e1a\u52a1\u903b\u8f91\u3002\u5b9e\u9a8c\u8fc7\u7a0b\u4e2d\u4e5f\u9047\u5230\u4e86\u4e00\u4e9b\u95ee\u9898\uff0c\u4f8b\u5982\u5916\u952e\u7ea6\u675f\u5bfc\u81f4\u6570\u636e\u65e0\u6cd5\u5220\u9664\u3001CHECK \u7ea6\u675f\u63d2\u5165\u5931\u8d25\u3001\u89e6\u53d1\u5668\u8bed\u6cd5\u9519\u8bef\u7b49\u3002\u901a\u8fc7\u67e5\u770b\u9519\u8bef\u4fe1\u606f\u3001\u4fee\u6539 SQL \u8bed\u53e5\u548c\u53cd\u590d\u6d4b\u8bd5\uff0c\u6700\u7ec8\u89e3\u51b3\u4e86\u8fd9\u4e9b\u95ee\u9898\u3002
\u200b
\u901a\u8fc7\u672c\u6b21\u5b9e\u9a8c\uff0c\u6211\u4e0d\u4ec5\u5de9\u56fa\u4e86\u6570\u636e\u5e93\u7406\u8bba\u77e5\u8bc6\uff0c\u4e5f\u63d0\u9ad8\u4e86 SQL \u7f16\u5199\u80fd\u529b\u548c\u6570\u636e\u5e93\u8c03\u8bd5\u80fd\u529b\u3002\u4eca\u540e\u5728\u8bbe\u8ba1\u6570\u636e\u5e93\u7cfb\u7edf<\/pre>\n","protected":false},"excerpt":{"rendered":"\u6570\u636e\u5e93\u7efc\u5408\u5b9e\u9a8c 1.\u9700\u6c42\u5206\u6790 \u67d0\u5927\u578b\u56fe\u4e66\u9986\u9700\u8981\u5f00\u53d1\u4e00\u5957\u6570\u5b57\u5316\u501f\u9605\u7ba1\u7406\u7cfb\u7edf\uff0c\u4e3b\u8981\u4e1a\u52a1\u9700\u6c42\u5982\u4e0b\uff1a \u56fe\u4e66\u4fe1\u606f\uff1a\u8bb0\u5f55\u56fe […]<\/p>\n","protected":false},"author":1,"featured_media":448,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[9],"tags":[],"class_list":["post-446","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-wenzhang"],"_links":{"self":[{"href":"https:\/\/fg2025.cn\/index.php\/wp-json\/wp\/v2\/posts\/446","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/fg2025.cn\/index.php\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/fg2025.cn\/index.php\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/fg2025.cn\/index.php\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/fg2025.cn\/index.php\/wp-json\/wp\/v2\/comments?post=446"}],"version-history":[{"count":0,"href":"https:\/\/fg2025.cn\/index.php\/wp-json\/wp\/v2\/posts\/446\/revisions"}],"wp:attachment":[{"href":"https:\/\/fg2025.cn\/index.php\/wp-json\/wp\/v2\/media?parent=446"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/fg2025.cn\/index.php\/wp-json\/wp\/v2\/categories?post=446"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/fg2025.cn\/index.php\/wp-json\/wp\/v2\/tags?post=446"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}
select count(*) as \u56fe\u4e66\u603b\u6570 from book;
2.\u7edf\u8ba1\u56fe\u4e66\u5e93\u5b58\u603b\u91cf
select sum(stock) as \u5e93\u5b58\u603b\u91cf from book;
3.\u7edf\u8ba1\u5e73\u5747\u5e93\u5b58
select avg(stock) as \u5e73\u5747\u5e93\u5b58 from book;
4.\u67e5\u8be2\u6700\u5927\u5e93\u5b58\u548c\u6700\u5c0f\u5e93\u5b58
SELECT MAX(stock) AS \u6700\u5927\u5e93\u5b58,
MIN(stock) AS \u6700\u5c0f\u5e93\u5b58
FROM book;
5.\u6309\u51fa\u7248\u793e\u7edf\u8ba1\u56fe\u4e66\u6570\u91cf\uff0c\u5e76\u7b5b\u9009\u6570\u91cf\u5927\u4e8e\u7b49\u4e8e1\u7684\u51fa\u7248\u793e
SELECT press, COUNT(*) AS \u56fe\u4e66\u6570\u91cf
FROM book
GROUP BY press
HAVING COUNT(*) >= 1;<\/pre>\n\n\n\n
8.\u591a\u8868\u8fde\u63a5\u67e5\u8be2<\/h2>\n\n\n\n1.\u7b49\u503c\u8fde\u63a5\uff1a\u67e5\u8be2\u8bfb\u8005\u59d3\u540d\u548c\u6240\u501f\u56fe\u4e66
SELECT reader.rname, book.bname
FROM reader, borrow, book
WHERE reader.rno = borrow.rno
AND borrow.bno = book.bno;
2.\u5185\u8fde\u63a5\uff1a\u67e5\u8be2\u501f\u9605\u8bb0\u5f55\u8be6\u60c5
SELECT r.rname, b.bname, br.borrowdate, br.returndate
FROM borrow br
JOIN reader r ON br.rno = r.rno
JOIN book b ON br.bno = b.bno;
3.\u5de6\u5916\u8fde\u63a5\uff1a\u67e5\u8be2\u6240\u6709\u8bfb\u8005\u53ca\u5176\u501f\u9605\u8bb0\u5f55
SELECT r.rno, r.rname, br.borrowid, br.bno
FROM reader r
LEFT JOIN borrow br
ON r.rno = br.rno;
4.\u53f3\u5916\u8fde\u63a5\uff1a\u67e5\u8be2\u6240\u6709\u501f\u9605\u8bb0\u5f55\u53ca\u8bfb\u8005\u4fe1\u606f
SELECT r.rname, br.borrowid, br.bno
FROM reader r
RIGHT JOIN borrow br
ON r.rno = br.rno;
5.\u81ea\u8eab\u8fde\u63a5\uff1a\u67e5\u8be2\u540c\u4e00\u5e74\u51fa\u7248\u7684\u4e0d\u540c\u56fe\u4e66
SELECT a.bname AS \u56fe\u4e661,
b.bname AS \u56fe\u4e662,
a.pubyear AS \u51fa\u7248\u5e74\u4efd
FROM book a
JOIN book b
ON a.pubyear = b.pubyear
AND a.bno < b.bno;<\/pre>\n\n\n\n9.\u5d4c\u5957\u67e5\u8be2<\/h2>\n\n\n\n1.IN\uff1a\u67e5\u8be2\u501f\u8fc7\u4e66\u7684\u8bfb\u8005
SELECT *
FROM reader
WHERE rno IN(
SELECT rno FROM borrow
);
2.\u6bd4\u8f83\u8fd0\u7b97\u7b26\uff1a\u67e5\u8be2\u5e93\u5b58\u5927\u4e8e\u5e73\u5747\u5e93\u5b58\u7684\u56fe\u4e66
SELECT bno,bname,stock
FROM book
WHERE stock > (
SELECT AVG(stock)
FROM book
);
3.EXISTS\uff1a\u67e5\u8be2\u5b58\u5728\u501f\u9605\u8bb0\u5f55\u7684\u8bfb\u8005
SELECT *
FROM reader r
WHERE EXISTS(
SELECT *
FROM borrow br
WHERE br.rno = r.rno
);
4.ANY\uff1a\u67e5\u8be2\u5e93\u5b58\u5927\u4e8e\u4efb\u610f\u4e00\u672c2018\u5e74\u51fa\u7248\u56fe\u4e66\u5e93\u5b58\u7684\u56fe\u4e66
SELECT bno,bname,stock
FROM book
WHERE stock > ANY(
SELECT stock
FROM book
WHERE pubyear = 2018
);
5.ALL\uff1a\u67e5\u8be2\u5e93\u5b58\u4e0d\u5c11\u4e8e\u6240\u6709\u56fe\u4e66\u5e93\u5b58\u7684\u56fe\u4e66
SELECT bno,bname,stock
FROM book
WHERE stock >= ALL(
SELECT stock
FROM book
);<\/pre>\n\n\n\n10.\u96c6\u5408\u67e5\u8be2<\/h2>\n\n\n\n1.UNION\uff1a\u5408\u5e76\u8bfb\u8005\u59d3\u540d\u548c\u4f5c\u8005\u59d3\u540d\u5e76\u53bb\u91cd
SELECT rname AS name
FROM reader
UNION
SELECT author AS name
FROM book;
2.UNION ALL\uff1a\u5408\u5e76\u8bfb\u8005\u59d3\u540d\u548c\u4f5c\u8005\u59d3\u540d\uff0c\u4e0d\u53bb\u91cd
SELECT rname AS name
FROM reader
UNION ALL
SELECT author AS name
FROM book;
3.\u6a21\u62df INTERSECT\uff1a\u67e5\u8be2\u501f\u8fc7\u4e66\u7684\u8bfb\u8005\u8bc1\u53f7
SELECT rno
FROM reader
WHERE rno IN(
SELECT rno
FROM borrow
);
4.\u6a21\u62df EXCEPT\uff1a\u67e5\u8be2\u6ca1\u6709\u501f\u4e66\u7684\u8bfb\u8005
SELECT rno,rname
FROM reader
WHERE rno NOT IN(
SELECT rno
FROM borrow
);<\/pre>\n\n\n\n11.\u89c6\u56fe\u64cd\u4f5c<\/h2>\n\n\n\n1.\u521b\u5efa\u672a\u5f52\u8fd8\u56fe\u4e66\u89c6\u56fe
CREATE VIEW v_unreturned AS
SELECT br.borrowid, r.rname, b.bname,
br.borrowdate, br.returndate
FROM borrow br
JOIN reader r ON br.rno = r.rno
JOIN book b ON br.bno = b.bno
WHERE br.actualdate IS NULL;
2.\u67e5\u8be2\u89c6\u56fe
SELECT * FROM v_unreturned;
3.\u521b\u5efa\u5b66\u751f\u8bfb\u8005\u89c6\u56fe\uff0c\u5e26 WITH CHECK OPTION
CREATE VIEW v_student_reader AS
SELECT *
FROM reader
WHERE dept LIKE '%\u5b66\u9662%'
WITH CHECK OPTION;
4.\u6d4b\u8bd5\u53ef\u66f4\u65b0\u89c6\u56fe
UPDATE v_student_reader
SET phone = '18800000000'
WHERE rno = 'R2024002';
\u8bf4\u660e\uff1a
\u8be5\u89c6\u56fe\u57fa\u4e8e\u5355\u8868 reader \u521b\u5efa\uff0c\u6ca1\u6709\u805a\u5408\u51fd\u6570\u3001\u5206\u7ec4\u548c\u8fde\u63a5\uff0c\u56e0\u6b64\u5c5e\u4e8e\u53ef\u66f4\u65b0\u89c6\u56fe\u3002
5.\u521b\u5efa\u4e0d\u53ef\u66f4\u65b0\u7684\u805a\u5408\u89c6\u56fe
CREATE VIEW v_press_count AS
SELECT press, COUNT(*) AS total
FROM book
GROUP BY press;
\u8bf4\u660e\uff1a
\u8be5\u89c6\u56fe\u4f7f\u7528\u4e86 GROUP BY \u548c COUNT \u805a\u5408\u51fd\u6570\uff0c\u56e0\u6b64\u4e00\u822c\u4e0d\u80fd\u76f4\u63a5\u66f4\u65b0\u3002
6.\u5220\u9664\u89c6\u56fe
DROP VIEW v_unreturned;
DROP VIEW v_student_reader;
DROP VIEW v_press_count;<\/pre>\n\n\n\n12.\u7d22\u5f15<\/h2>\n\n\n\n1.\u521b\u5efa\u666e\u901a\u7d22\u5f15
CREATE INDEX idx_book_bname
ON book(bname);
2.\u521b\u5efa\u552f\u4e00\u7d22\u5f15
CREATE UNIQUE INDEX idx_reader_phone
ON reader(phone);
3.\u521b\u5efa\u590d\u5408\u7d22\u5f15
CREATE INDEX idx_borrow_rno_bno
ON borrow(rno,bno);
\u67e5\u770b\u7d22\u5f15
SHOW INDEX FROM book;
SHOW INDEX FROM reader;
SHOW INDEX FROM borrow;
\u5220\u9664\u7d22\u5f15
DROP INDEX idx_book_bname ON book;
DROP INDEX idx_reader_phone ON reader;
DROP INDEX idx_borrow_rno_bno ON borrow;<\/pre>\n\n\n\n13.\u6570\u636e\u5b8c\u6574\u6027\u7ea6\u675f\u9a8c\u8bc1\u4e0e\u7ea7\u8054\u64cd\u4f5c<\/h2>\n\n\n\n1.\u5b9e\u4f53\u5b8c\u6574\u6027\u9a8c\u8bc1\uff1a\u4e3b\u952e\u4e0d\u80fd\u4e3a\u7a7a
INSERT INTO book(bno,bname,author,press,pubyear,stock)
VALUES(NULL,'\u6d4b\u8bd5\u4e66','\u6d4b\u8bd5\u4f5c\u8005','\u6d4b\u8bd5\u51fa\u7248\u793e',2020,1);
\u8bf4\u660e\uff1a
bno \u662f book \u8868\u4e3b\u952e\uff0c\u4e3b\u952e\u4e0d\u80fd\u4e3a\u7a7a\uff0c\u56e0\u6b64\u63d2\u5165\u5931\u8d25\u3002
2.\u53c2\u7167\u5b8c\u6574\u6027\u9a8c\u8bc1\uff1a\u63d2\u5165\u4e0d\u5b58\u5728\u7684\u56fe\u4e66\u7f16\u53f7
INSERT INTO borrow(rno,bno,borrowdate,returndate,actualdate)
VALUES('R2024001','B999','2025-05-01','2025-05-15',NULL);
\u8bf4\u660e\uff1a
B999 \u5728 book \u8868\u4e2d\u4e0d\u5b58\u5728\uff0cborrow.bno \u662f\u5916\u952e\uff0c\u56e0\u6b64\u8fdd\u53cd\u53c2\u7167\u5b8c\u6574\u6027\u3002
3.\u7528\u6237\u5b9a\u4e49\u5b8c\u6574\u6027\u9a8c\u8bc1\uff1a\u5e93\u5b58\u4e0d\u80fd\u5c0f\u4e8e0
UPDATE book
SET stock = -1
WHERE bno = 'B001';
\u8bf4\u660e\uff1a
stock \u5b57\u6bb5\u8bbe\u7f6e\u4e86 CHECK(stock>=0)\uff0c\u5e93\u5b58\u4e0d\u80fd\u4e3a\u8d1f\u6570\u3002
4.\u7528\u6237\u5b9a\u4e49\u5b8c\u6574\u6027\u9a8c\u8bc1\uff1a\u5e93\u5b58\u4e0d\u80fd\u5c0f\u4e8e0
UPDATE book
SET stock = -1
WHERE bno = 'B001';
\u8bf4\u660e\uff1a
stock \u5b57\u6bb5\u8bbe\u7f6e\u4e86 CHECK(stock>=0)\uff0c\u5e93\u5b58\u4e0d\u80fd\u4e3a\u8d1f\u6570\u3002
5.ON UPDATE CASCADE \u6d4b\u8bd5
UPDATE reader
SET rno = 'R2024999'
WHERE rno = 'R2024003';
SELECT * FROM borrow
WHERE rno = 'R2024999';
\u8bf4\u660e\uff1a
reader.rno \u66f4\u65b0\u540e\uff0cborrow \u8868\u4e2d\u5bf9\u5e94\u7684\u5916\u952e rno \u4f1a\u81ea\u52a8\u540c\u6b65\u66f4\u65b0\u3002<\/pre>\n\n\n\n14.\u89e6\u53d1\u5668<\/h2>\n\n\n\n\u51c6\u5907\uff1a\u5220\u9664\u65e7\u89e6\u53d1\u5668
DROP TRIGGER IF EXISTS trg_borrow_before_insert;
DROP TRIGGER IF EXISTS trg_return_after_update;
DROP TRIGGER IF EXISTS trg_reader_before_delete;
\u521b\u5efa\u5220\u9664\u8bfb\u8005\u65e5\u5fd7\u8868
CREATE TABLE reader_delete_log(
logid INT AUTO_INCREMENT PRIMARY KEY,
rno CHAR(12),
rname VARCHAR(20),
dept VARCHAR(40),
delete_time DATETIME DEFAULT CURRENT_TIMESTAMP
);
1.\u501f\u4e66\u65f6\u81ea\u52a8\u51cf\u5c11\u5e93\u5b58
DELIMITER \/\/
CREATE TRIGGER trg_borrow_before_insert
BEFORE INSERT ON borrow
FOR EACH ROW
BEGIN
DECLARE v_stock INT;
SELECT stock INTO v_stock
FROM book
WHERE bno = NEW.bno;
IF v_stock <= 0 THEN
SIGNAL SQLSTATE '45000'
SET MESSAGE_TEXT = '\u5e93\u5b58\u4e0d\u8db3\uff0c\u4e0d\u80fd\u501f\u4e66';
ELSE
UPDATE book
SET stock = stock - 1
WHERE bno = NEW.bno;
END IF;
END \/\/
DELIMITER ;
\u6d4b\u8bd5\uff1a
SELECT stock FROM book WHERE bno='B003';
INSERT INTO borrow(rno,bno,borrowdate,returndate,actualdate)
VALUES('R2024002','B003','2025-05-01','2025-05-15',NULL);
SELECT stock FROM book WHERE bno='B003';
2.\u8fd8\u4e66\u65f6\u81ea\u52a8\u589e\u52a0\u5e93\u5b58\u5e76\u8ba1\u7b97\u7f5a\u6b3e
DELIMITER \/\/
CREATE TRIGGER trg_return_after_update
AFTER UPDATE ON borrow
FOR EACH ROW
BEGIN
IF OLD.actualdate IS NULL AND NEW.actualdate IS NOT NULL THEN
UPDATE book
SET stock = stock + 1
WHERE bno = NEW.bno;
UPDATE borrow
SET fine =
CASE
WHEN NEW.actualdate > NEW.returndate
THEN DATEDIFF(NEW.actualdate, NEW.returndate) * 1
ELSE 0
END
WHERE borrowid = NEW.borrowid;
END IF;
END \/\/
DELIMITER ;
\u6d4b\u8bd5\uff1a
UPDATE borrow
SET actualdate = '2025-05-18'
WHERE rno='R2024002'
AND bno='B003'
AND borrowdate='2025-05-01';
SELECT * FROM borrow
WHERE rno='R2024002'
AND bno='B003';
SELECT stock FROM book WHERE bno='B003';
3.\u5220\u9664\u8bfb\u8005\u524d\u8bb0\u5f55\u65e5\u5fd7
DELIMITER \/\/
CREATE TRIGGER trg_reader_before_delete
BEFORE DELETE ON reader
FOR EACH ROW
BEGIN
INSERT INTO reader_delete_log(rno,rname,dept)
VALUES(OLD.rno, OLD.rname, OLD.dept);
END \/\/
DELIMITER ;
\u6d4b\u8bd5\uff1a
INSERT INTO reader
VALUES('R2024888','\u65e5\u5fd7\u6d4b\u8bd5','\u7537','\u6d4b\u8bd5\u5b66\u9662','\u65e0');
DELETE FROM reader
WHERE rno='R2024888';
SELECT * FROM reader_delete_log;<\/pre>\n\n\n\n15.\u6570\u636e\u5b89\u5168\u6027<\/h2>\n\n\n\n1.\u521b\u5efa\u7528\u6237\u5e76\u6388\u4e88\u67e5\u8be2\u6743\u9650
CREATE USER 'lib_user1'@'localhost'
IDENTIFIED BY '123456';
GRANT SELECT
ON library_db.book
TO 'lib_user1'@'localhost';
\u67e5\u770b\u6743\u9650\uff1a
SHOW GRANTS FOR 'lib_user1'@'localhost';
2.\u6388\u4e88\u6743\u9650\u5e76\u5141\u8bb8\u8f6c\u6388\u6743
GRANT SELECT, INSERT
ON library_db.reader
TO 'lib_user1'@'localhost'
WITH GRANT OPTION;
\u8bf4\u660e\uff1a
WITH GRANT OPTION \u8868\u793a\u8be5\u7528\u6237\u53ef\u4ee5\u5c06\u81ea\u5df1\u62e5\u6709\u7684\u6743\u9650\u518d\u6388\u4e88\u5176\u4ed6\u7528\u6237\u3002
3.\u56de\u6536\u6743\u9650
REVOKE INSERT
ON library_db.reader
FROM 'lib_user1'@'localhost';
4.\u521b\u5efa\u89d2\u8272\u5e76\u6388\u6743
CREATE ROLE 'reader_role';
GRANT SELECT
ON library_db.*
TO 'reader_role';
CREATE USER 'lib_user2'@'localhost'
IDENTIFIED BY '123456';
GRANT 'reader_role'
TO 'lib_user2'@'localhost';
SET DEFAULT ROLE 'reader_role'
TO 'lib_user2'@'localhost';<\/pre>\n\n\n\n16.\u89c6\u56fe\u4e0e\u6d3e\u751f\u8868<\/h2>\n\n\n\n1.\u5e26\u805a\u5408\u51fd\u6570\u7684\u89c6\u56fe\uff1a\u7edf\u8ba1\u6bcf\u4e2a\u8bfb\u8005\u501f\u9605\u6b21\u6570
CREATE VIEW v_reader_borrow_count AS
SELECT r.rno, r.rname, COUNT(br.borrowid) AS borrow_count
FROM reader r
LEFT JOIN borrow br
ON r.rno = br.rno
GROUP BY r.rno, r.rname;
\u67e5\u8be2\uff1a
SELECT * FROM v_reader_borrow_count;
2.\u6d3e\u751f\u8868\uff1a\u67e5\u8be2\u501f\u9605\u6b21\u6570\u5927\u4e8e1\u7684\u8bfb\u8005
SELECT *
FROM (
SELECT rno, COUNT(*) AS borrow_count
FROM borrow
GROUP BY rno
) AS t
WHERE t.borrow_count > 1;
3.WITH \u5b50\u53e5\u7edf\u8ba1\u6bcf\u4f4d\u8bfb\u8005\u501f\u9605\u6570\u91cf
WITH reader_count AS (
SELECT rno, COUNT(*) AS total
FROM borrow
GROUP BY rno
)
SELECT r.rno, r.rname, rc.total
FROM reader r
LEFT JOIN reader_count rc
ON r.rno = rc.rno;
4.WITH \u5b50\u53e5\uff1a\u67e5\u8be2\u672a\u5f52\u8fd8\u56fe\u4e66
WITH unreturned AS (
SELECT br.borrowid, r.rname, b.bname,
br.borrowdate, br.returndate
FROM borrow br
JOIN reader r ON br.rno = r.rno
JOIN book b ON br.bno = b.bno
WHERE br.actualdate IS NULL
)
SELECT * FROM unreturned;<\/pre>\n\n\n\n17.\u6269\u5c55\u601d\u8003<\/h2>\n\n\n\n\n- \u5982\u4f55\u5904\u7406\u5206\u7c7b\u5b9e\u4f53\u7684\u81ea\u5173\u8054\uff1f<\/li>\n<\/ol>\n\n\n\n
\u5206\u7c7b\u5b9e\u4f53\u5b58\u5728\u201c\u4e0a\u7ea7\u5206\u7c7b\u201d\u548c\u201c\u4e0b\u7ea7\u5206\u7c7b\u201d\u7684\u5173\u7cfb\uff0c\u56e0\u6b64\u53ef\u4ee5\u5728 category \u8868\u4e2d\u8bbe\u7f6e parentid \u5b57\u6bb5\u3002
category(
cid,
cname,
parentid
)
\u5176\u4e2d cid \u662f\u5206\u7c7b\u7f16\u53f7\uff0cparentid \u662f\u4e0a\u7ea7\u5206\u7c7b\u7f16\u53f7\uff0c\u540c\u65f6 parentid \u4e5f\u662f\u6307\u5411 category.cid \u7684\u5916\u952e\u3002
\u5982\u679c\u67d0\u5206\u7c7b\u6ca1\u6709\u4e0a\u7ea7\u5206\u7c7b\uff0c\u5219 parentid \u53ef\u4ee5\u4e3a\u7a7a\u3002
\u8fd9\u79cd\u8bbe\u8ba1\u53ef\u4ee5\u8868\u793a\u6811\u5f62\u7ed3\u6784\uff0c\u4f8b\u5982\uff1a
\u56fe\u4e66
\u251c\u2500\u2500 \u8ba1\u7b97\u673a
\u2502 \u251c\u2500\u2500 \u6570\u636e\u5e93
\u2502 \u2514\u2500\u2500 \u7f51\u7edc\u6280\u672f
\u2514\u2500\u2500 \u6587\u5b66
\u2514\u2500\u2500 \u79d1\u5e7b\u5c0f\u8bf4<\/pre>\n\n\n\n
\n\n\n\n2. \u501f\u9605\u5173\u7cfb\u662f\u5426\u53ef\u80fd\u5b58\u5728\u6570\u636e\u5197\u4f59\uff1f<\/h2>\n\n\n\n\u501f\u9605\u8868\u5982\u679c\u53ea\u4fdd\u5b58 rno\u3001bno\u3001borrowdate\u3001returndate\u3001actualdate \u7b49\u4fe1\u606f\uff0c\u5219\u5197\u4f59\u8f83\u5c11\u3002
\u4f46\u662f\u5982\u679c\u5728 borrow \u8868\u4e2d\u540c\u65f6\u4fdd\u5b58\u8bfb\u8005\u59d3\u540d rname\u3001\u56fe\u4e66\u540d\u79f0 bname\u3001\u51fa\u7248\u793e press \u7b49\u4fe1\u606f\uff0c\u5c31\u4f1a\u4ea7\u751f\u6570\u636e\u5197\u4f59\u3002
\u4f8b\u5982\uff1a
borrow(borrowid, rno, rname, bno, bname, borrowdate)
\u5176\u4e2d rname \u4f9d\u8d56 rno\uff0cbname \u4f9d\u8d56 bno\uff0c\u800c\u4e0d\u662f\u76f4\u63a5\u4f9d\u8d56 borrowid\uff0c\u4f1a\u4ea7\u751f\u4f20\u9012\u4f9d\u8d56\u3002
\u89c4\u8303\u5316\u65b9\u6848\uff1a
\u5c06\u8bfb\u8005\u4fe1\u606f\u4fdd\u5b58\u5728 reader \u8868\uff1b
\u5c06\u56fe\u4e66\u4fe1\u606f\u4fdd\u5b58\u5728 book \u8868\uff1b
borrow \u8868\u53ea\u4fdd\u5b58\u8bfb\u8005\u8bc1\u53f7\u548c\u56fe\u4e66\u7f16\u53f7\u4f5c\u4e3a\u5916\u952e\u3002<\/pre>\n\n\n\n
\n\n\n\n3. \u5982\u4f55\u9632\u6b62\u5e93\u5b58\u4e3a\u8d1f\u6570\uff1f<\/h2>\n\n\n\n\u53ef\u4ee5\u4ece\u4e24\u4e2a\u65b9\u9762\u9632\u6b62\u5e93\u5b58\u4e3a\u8d1f\u6570\uff1a
\u7b2c\u4e00\uff0c\u5728 book \u8868\u4e2d\u8bbe\u7f6e CHECK(stock >= 0) \u7ea6\u675f\uff0c\u4fdd\u8bc1\u5e93\u5b58\u4e0d\u80fd\u5c0f\u4e8e0\u3002
\u7b2c\u4e8c\uff0c\u5728\u501f\u4e66\u89e6\u53d1\u5668\u4e2d\u5224\u65ad\u5e93\u5b58\u6570\u91cf\u3002
\u5f53\u63d2\u5165 borrow \u501f\u9605\u8bb0\u5f55\u65f6\uff0c\u5148\u67e5\u8be2\u56fe\u4e66\u5e93\u5b58\u3002
\u5982\u679c\u5e93\u5b58\u5c0f\u4e8e\u7b49\u4e8e0\uff0c\u5219\u4f7f\u7528 SIGNAL \u629b\u51fa\u9519\u8bef\uff0c\u963b\u6b62\u501f\u4e66\u64cd\u4f5c\uff1b
\u5982\u679c\u5e93\u5b58\u5927\u4e8e0\uff0c\u5219\u5141\u8bb8\u501f\u9605\uff0c\u5e76\u81ea\u52a8\u5c06\u5e93\u5b58\u51cf1\u3002
\u8fd9\u6837\u53ef\u4ee5\u4fdd\u8bc1\u501f\u4e66\u65f6\u4e0d\u4f1a\u51fa\u73b0\u5e93\u5b58\u4e3a\u8d1f\u6570\u7684\u60c5\u51b5\u3002<\/pre>\n\n\n\n
\n\n\n\n4. \u9884\u7ea6\u56fe\u4e66\u529f\u80fd\u9700\u8981\u589e\u52a0\u54ea\u4e9b\u5b9e\u4f53\u548c\u5173\u7cfb\uff1f<\/h2>\n\n\n\n\u5982\u679c\u7cfb\u7edf\u652f\u6301\u9884\u7ea6\u56fe\u4e66\u529f\u80fd\uff0c\u53ef\u4ee5\u589e\u52a0 reservation \u9884\u7ea6\u8868\u3002
reservation(
reserveid,
rno,
bno,
reservedate,
status
)
\u5176\u4e2d\uff1a
reserveid \u8868\u793a\u9884\u7ea6\u7f16\u53f7\uff1b
rno \u662f\u8bfb\u8005\u8bc1\u53f7\uff0c\u5916\u952e\u5f15\u7528 reader.rno\uff1b
bno \u662f\u56fe\u4e66\u7f16\u53f7\uff0c\u5916\u952e\u5f15\u7528 book.bno\uff1b
reservedate \u8868\u793a\u9884\u7ea6\u65e5\u671f\uff1b
status \u8868\u793a\u9884\u7ea6\u72b6\u6001\uff0c\u5982\u201c\u9884\u7ea6\u4e2d\u201d\u201c\u5df2\u53d6\u6d88\u201d\u201c\u5df2\u5b8c\u6210\u201d\u3002
\u65b0\u589e\u5173\u7cfb\uff1a
\u4e00\u4e2a\u8bfb\u8005\u53ef\u4ee5\u9884\u7ea6\u591a\u672c\u56fe\u4e66\uff1b
\u4e00\u672c\u56fe\u4e66\u53ef\u4ee5\u88ab\u591a\u4e2a\u8bfb\u8005\u9884\u7ea6\uff1b
\u8bfb\u8005\u548c\u56fe\u4e66\u4e4b\u95f4\u901a\u8fc7 reservation \u8868\u5f62\u6210 m:n \u8054\u7cfb\u3002<\/pre>\n\n\n\n
\n\n\n\n5. \u4e3a\u4ec0\u4e48\u9075\u5faa\u6700\u5c0f\u6743\u9650\u539f\u5219\uff1f<\/h2>\n\n\n\n\u6700\u5c0f\u6743\u9650\u539f\u5219\u662f\u6307\u53ea\u7ed9\u7528\u6237\u5b8c\u6210\u5de5\u4f5c\u6240\u5fc5\u9700\u7684\u6743\u9650\uff0c\u4e0d\u6388\u4e88\u591a\u4f59\u6743\u9650\u3002
\u5728\u672c\u5b9e\u9a8c\u4e2d\uff0c\u5982\u679c\u67d0\u7528\u6237\u53ea\u8d1f\u8d23\u67e5\u8be2\u56fe\u4e66\u4fe1\u606f\uff0c\u5219\u53ea\u6388\u4e88 SELECT \u6743\u9650\u5373\u53ef\uff0c\u4e0d\u5e94\u8be5\u6388\u4e88 INSERT\u3001UPDATE\u3001DELETE \u7b49\u6743\u9650\u3002
\u4f8b\u5982\uff1a
GRANT SELECT ON library_db.book TO 'lib_user1'@'localhost';
\u8fd9\u6837\u53ef\u4ee5\u9632\u6b62\u7528\u6237\u8bef\u5220\u3001\u8bef\u6539\u6570\u636e\uff0c\u63d0\u9ad8\u6570\u636e\u5e93\u5b89\u5168\u6027\u3002
\u5982\u679c\u540e\u7eed\u4e0d\u518d\u9700\u8981\u67d0\u9879\u6743\u9650\uff0c\u8fd8\u53ef\u4ee5\u4f7f\u7528 REVOKE \u56de\u6536\u6743\u9650\u3002<\/pre>\n\n\n\n
\n\n\n\n6. \u5e76\u53d1\u501f\u9605\u5e93\u5b58\u4ec5\u52691\u672c\u7684\u56fe\u4e66\u4f1a\u4ea7\u751f\u4ec0\u4e48\u95ee\u9898\uff1f\u5982\u4f55\u89e3\u51b3\uff1f<\/h2>\n\n\n\n\u5f53\u591a\u7528\u6237\u540c\u65f6\u501f\u9605\u540c\u4e00\u672c\u5e93\u5b58\u4ec5\u52691\u672c\u7684\u56fe\u4e66\u65f6\uff0c\u53ef\u80fd\u51fa\u73b0\u8d85\u5356\u95ee\u9898\u3002
\u4f8b\u5982\u4e24\u4e2a\u7528\u6237\u540c\u65f6\u8bfb\u53d6\u5e93\u5b58 stock=1\uff0c\u90fd\u8ba4\u4e3a\u53ef\u4ee5\u501f\u9605\uff0c\u7136\u540e\u540c\u65f6\u63d2\u5165\u501f\u9605\u8bb0\u5f55\u5e76\u6267\u884c\u5e93\u5b58\u51cf1\uff0c\u6700\u7ec8\u53ef\u80fd\u5bfc\u81f4\u5e93\u5b58\u5f02\u5e38\u6216\u51fa\u73b0\u8d85\u989d\u501f\u9605\u3002
\u89e3\u51b3\u65b9\u6cd5\uff1a
1. \u4f7f\u7528\u4e8b\u52a1\u4fdd\u8bc1\u501f\u4e66\u64cd\u4f5c\u7684\u539f\u5b50\u6027\uff1b
2. \u4f7f\u7528 SELECT ... FOR UPDATE \u5bf9\u56fe\u4e66\u5e93\u5b58\u8bb0\u5f55\u52a0\u884c\u7ea7\u9501\uff1b
3. \u5728\u89e6\u53d1\u5668\u4e2d\u5224\u65ad\u5e93\u5b58\u662f\u5426\u5927\u4e8e0\uff1b
4. \u7ed9 stock \u5b57\u6bb5\u8bbe\u7f6e CHECK(stock >= 0) \u7ea6\u675f\u3002
\u793a\u4f8b\uff1a
START TRANSACTION;
SELECT stock
FROM book
WHERE bno='B001'
FOR UPDATE;
UPDATE book
SET stock = stock - 1
WHERE bno='B001'
AND stock > 0;
INSERT INTO borrow(rno,bno,borrowdate,returndate)
VALUES('R2024001','B001','2025-05-01','2025-05-15');
COMMIT;
\u8fd9\u6837\u53ef\u4ee5\u907f\u514d\u591a\u4e2a\u7528\u6237\u540c\u65f6\u4fee\u6539\u5e93\u5b58\u5bfc\u81f4\u6570\u636e\u4e0d\u4e00\u81f4\u3002<\/pre>\n\n\n\n
\n\n\n\n\u5b9e\u9a8c\u603b\u7ed3<\/h1>\n\n\n\n \u901a\u8fc7\u672c\u6b21\u56fe\u4e66\u501f\u9605\u7ba1\u7406\u7cfb\u7edf\u7efc\u5408\u5b9e\u9a8c\uff0c\u6211\u7cfb\u7edf\u5730\u5b8c\u6210\u4e86\u6570\u636e\u5e93\u8bbe\u8ba1\u4e0e\u5b9e\u73b0\u7684\u5168\u8fc7\u7a0b\u3002\u5b9e\u9a8c\u4ece\u9700\u6c42\u5206\u6790\u5f00\u59cb\uff0c\u9010\u6b65\u5b8c\u6210 E-R \u56fe\u8bbe\u8ba1\u3001\u5173\u7cfb\u6a21\u5f0f\u8f6c\u6362\u3001\u7269\u7406\u8868\u7ed3\u6784\u8bbe\u8ba1\u3001\u6570\u636e\u63d2\u5165\u3001\u67e5\u8be2\u64cd\u4f5c\u3001\u89c6\u56fe\u3001\u7d22\u5f15\u3001\u5b8c\u6574\u6027\u7ea6\u675f\u3001\u89e6\u53d1\u5668\u548c\u6743\u9650\u7ba1\u7406\u7b49\u5185\u5bb9\uff0c\u4f7f\u6211\u5bf9\u6570\u636e\u5e93\u5e94\u7528\u7cfb\u7edf\u7684\u8bbe\u8ba1\u6d41\u7a0b\u6709\u4e86\u66f4\u52a0\u5b8c\u6574\u7684\u8ba4\u8bc6\u3002
\u200b
\u5728\u5b9e\u9a8c\u8fc7\u7a0b\u4e2d\uff0c\u6211\u9996\u5148\u6839\u636e\u56fe\u4e66\u9986\u4e1a\u52a1\u9700\u6c42\u5206\u6790\u51fa\u56fe\u4e66\u3001\u8bfb\u8005\u3001\u501f\u9605\u3001\u51fa\u7248\u793e\u3001\u5206\u7c7b\u7b49\u5b9e\u4f53\uff0c\u5e76\u660e\u786e\u4e86\u5b83\u4eec\u4e4b\u95f4\u7684\u8054\u7cfb\u7c7b\u578b\u3002\u4f8b\u5982\uff0c\u51fa\u7248\u793e\u4e0e\u56fe\u4e66\u4e4b\u95f4\u662f\u4e00\u5bf9\u591a\u5173\u7cfb\uff0c\u5206\u7c7b\u4e0e\u56fe\u4e66\u4e4b\u95f4\u662f\u4e00\u5bf9\u591a\u5173\u7cfb\uff0c\u8bfb\u8005\u4e0e\u56fe\u4e66\u4e4b\u95f4\u901a\u8fc7\u501f\u9605\u8868\u5f62\u6210\u591a\u5bf9\u591a\u5173\u7cfb\u3002\u901a\u8fc7 E-R \u56fe\u8bbe\u8ba1\uff0c\u6211\u8fdb\u4e00\u6b65\u7406\u89e3\u4e86\u6982\u5ff5\u7ed3\u6784\u8bbe\u8ba1\u5728\u6570\u636e\u5e93\u5f00\u53d1\u4e2d\u7684\u91cd\u8981\u4f5c\u7528\u3002
\u200b
\u5728\u903b\u8f91\u7ed3\u6784\u8bbe\u8ba1\u9636\u6bb5\uff0c\u6211\u5c06 E-R \u56fe\u8f6c\u6362\u4e3a\u5173\u7cfb\u6a21\u5f0f\uff0c\u5e76\u5206\u6790\u5404\u8868\u662f\u5426\u6ee1\u8db3\u7b2c\u4e09\u8303\u5f0f\u3002\u901a\u8fc7\u89c4\u8303\u5316\u8bbe\u8ba1\uff0c\u907f\u514d\u4e86\u5728\u501f\u9605\u8868\u4e2d\u91cd\u590d\u4fdd\u5b58\u8bfb\u8005\u59d3\u540d\u3001\u56fe\u4e66\u540d\u79f0\u7b49\u4fe1\u606f\uff0c\u51cf\u5c11\u4e86\u6570\u636e\u5197\u4f59\uff0c\u63d0\u9ad8\u4e86\u6570\u636e\u4e00\u81f4\u6027\u3002\u5728\u7269\u7406\u8bbe\u8ba1\u9636\u6bb5\uff0c\u6211\u4f7f\u7528 SQL \u521b\u5efa\u6570\u636e\u5e93\u548c\u6570\u636e\u8868\uff0c\u8bbe\u7f6e\u4e86\u4e3b\u952e\u3001\u5916\u952e\u3001\u975e\u7a7a\u3001\u9ed8\u8ba4\u503c\u548c CHECK \u7ea6\u675f\uff0c\u5bf9\u5b9e\u4f53\u5b8c\u6574\u6027\u3001\u53c2\u7167\u5b8c\u6574\u6027\u548c\u7528\u6237\u5b9a\u4e49\u5b8c\u6574\u6027\u6709\u4e86\u66f4\u6df1\u523b\u7684\u7406\u89e3\u3002
\u200b
\u5728\u6570\u636e\u64cd\u4f5c\u90e8\u5206\uff0c\u6211\u7ec3\u4e60\u4e86 INSERT\u3001UPDATE\u3001DELETE \u548c SELECT \u8bed\u53e5\uff0c\u5e76\u5b8c\u6210\u4e86\u57fa\u7840\u67e5\u8be2\u3001\u805a\u5408\u67e5\u8be2\u3001\u591a\u8868\u8fde\u63a5\u67e5\u8be2\u3001\u5d4c\u5957\u67e5\u8be2\u548c\u96c6\u5408\u67e5\u8be2\u7b49\u5185\u5bb9\u3002\u901a\u8fc7\u8fd9\u4e9b\u7ec3\u4e60\uff0c\u6211\u638c\u63e1\u4e86 SQL \u67e5\u8be2\u8bed\u53e5\u7684\u5e38\u89c1\u5199\u6cd5\uff0c\u5c24\u5176\u662f\u591a\u8868\u8fde\u63a5\u548c\u5d4c\u5957\u67e5\u8be2\u7684\u4f7f\u7528\u65b9\u6cd5\u3002\u5b9e\u9a8c\u4e2d\u8fd8\u521b\u5efa\u4e86\u89c6\u56fe\u548c\u7d22\u5f15\uff0c\u7406\u89e3\u4e86\u89c6\u56fe\u53ef\u4ee5\u7b80\u5316\u590d\u6742\u67e5\u8be2\uff0c\u7d22\u5f15\u53ef\u4ee5\u63d0\u9ad8\u67e5\u8be2\u6548\u7387\uff0c\u4f46\u4e5f\u4f1a\u589e\u52a0\u7ef4\u62a4\u6210\u672c\u3002
\u200b
\u5728\u89e6\u53d1\u5668\u90e8\u5206\uff0c\u6211\u5b9e\u73b0\u4e86\u501f\u4e66\u81ea\u52a8\u51cf\u5c11\u5e93\u5b58\u3001\u8fd8\u4e66\u81ea\u52a8\u589e\u52a0\u5e93\u5b58\u5e76\u8ba1\u7b97\u7f5a\u6b3e\u3001\u5220\u9664\u8bfb\u8005\u524d\u8bb0\u5f55\u65e5\u5fd7\u7b49\u529f\u80fd\u3002\u901a\u8fc7\u89e6\u53d1\u5668\u5b9e\u9a8c\uff0c\u6211\u8ba4\u8bc6\u5230\u6570\u636e\u5e93\u4e0d\u4ec5\u53ef\u4ee5\u5b58\u50a8\u6570\u636e\uff0c\u8fd8\u53ef\u4ee5\u5728\u7279\u5b9a\u64cd\u4f5c\u53d1\u751f\u65f6\u81ea\u52a8\u6267\u884c\u4e00\u4e9b\u4e1a\u52a1\u903b\u8f91\u3002\u5b9e\u9a8c\u8fc7\u7a0b\u4e2d\u4e5f\u9047\u5230\u4e86\u4e00\u4e9b\u95ee\u9898\uff0c\u4f8b\u5982\u5916\u952e\u7ea6\u675f\u5bfc\u81f4\u6570\u636e\u65e0\u6cd5\u5220\u9664\u3001CHECK \u7ea6\u675f\u63d2\u5165\u5931\u8d25\u3001\u89e6\u53d1\u5668\u8bed\u6cd5\u9519\u8bef\u7b49\u3002\u901a\u8fc7\u67e5\u770b\u9519\u8bef\u4fe1\u606f\u3001\u4fee\u6539 SQL \u8bed\u53e5\u548c\u53cd\u590d\u6d4b\u8bd5\uff0c\u6700\u7ec8\u89e3\u51b3\u4e86\u8fd9\u4e9b\u95ee\u9898\u3002
\u200b
\u901a\u8fc7\u672c\u6b21\u5b9e\u9a8c\uff0c\u6211\u4e0d\u4ec5\u5de9\u56fa\u4e86\u6570\u636e\u5e93\u7406\u8bba\u77e5\u8bc6\uff0c\u4e5f\u63d0\u9ad8\u4e86 SQL \u7f16\u5199\u80fd\u529b\u548c\u6570\u636e\u5e93\u8c03\u8bd5\u80fd\u529b\u3002\u4eca\u540e\u5728\u8bbe\u8ba1\u6570\u636e\u5e93\u7cfb\u7edf<\/pre>\n","protected":false},"excerpt":{"rendered":"\u6570\u636e\u5e93\u7efc\u5408\u5b9e\u9a8c 1.\u9700\u6c42\u5206\u6790 \u67d0\u5927\u578b\u56fe\u4e66\u9986\u9700\u8981\u5f00\u53d1\u4e00\u5957\u6570\u5b57\u5316\u501f\u9605\u7ba1\u7406\u7cfb\u7edf\uff0c\u4e3b\u8981\u4e1a\u52a1\u9700\u6c42\u5982\u4e0b\uff1a \u56fe\u4e66\u4fe1\u606f\uff1a\u8bb0\u5f55\u56fe […]<\/p>\n","protected":false},"author":1,"featured_media":448,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[9],"tags":[],"class_list":["post-446","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-wenzhang"],"_links":{"self":[{"href":"https:\/\/fg2025.cn\/index.php\/wp-json\/wp\/v2\/posts\/446","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/fg2025.cn\/index.php\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/fg2025.cn\/index.php\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/fg2025.cn\/index.php\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/fg2025.cn\/index.php\/wp-json\/wp\/v2\/comments?post=446"}],"version-history":[{"count":0,"href":"https:\/\/fg2025.cn\/index.php\/wp-json\/wp\/v2\/posts\/446\/revisions"}],"wp:attachment":[{"href":"https:\/\/fg2025.cn\/index.php\/wp-json\/wp\/v2\/media?parent=446"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/fg2025.cn\/index.php\/wp-json\/wp\/v2\/categories?post=446"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/fg2025.cn\/index.php\/wp-json\/wp\/v2\/tags?post=446"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}
SELECT reader.rname, book.bname
FROM reader, borrow, book
WHERE reader.rno = borrow.rno
AND borrow.bno = book.bno;
2.\u5185\u8fde\u63a5\uff1a\u67e5\u8be2\u501f\u9605\u8bb0\u5f55\u8be6\u60c5
SELECT r.rname, b.bname, br.borrowdate, br.returndate
FROM borrow br
JOIN reader r ON br.rno = r.rno
JOIN book b ON br.bno = b.bno;
3.\u5de6\u5916\u8fde\u63a5\uff1a\u67e5\u8be2\u6240\u6709\u8bfb\u8005\u53ca\u5176\u501f\u9605\u8bb0\u5f55
SELECT r.rno, r.rname, br.borrowid, br.bno
FROM reader r
LEFT JOIN borrow br
ON r.rno = br.rno;
4.\u53f3\u5916\u8fde\u63a5\uff1a\u67e5\u8be2\u6240\u6709\u501f\u9605\u8bb0\u5f55\u53ca\u8bfb\u8005\u4fe1\u606f
SELECT r.rname, br.borrowid, br.bno
FROM reader r
RIGHT JOIN borrow br
ON r.rno = br.rno;
5.\u81ea\u8eab\u8fde\u63a5\uff1a\u67e5\u8be2\u540c\u4e00\u5e74\u51fa\u7248\u7684\u4e0d\u540c\u56fe\u4e66
SELECT a.bname AS \u56fe\u4e661,
b.bname AS \u56fe\u4e662,
a.pubyear AS \u51fa\u7248\u5e74\u4efd
FROM book a
JOIN book b
ON a.pubyear = b.pubyear
AND a.bno < b.bno;<\/pre>\n\n\n\n
9.\u5d4c\u5957\u67e5\u8be2<\/h2>\n\n\n\n1.IN\uff1a\u67e5\u8be2\u501f\u8fc7\u4e66\u7684\u8bfb\u8005
SELECT *
FROM reader
WHERE rno IN(
SELECT rno FROM borrow
);
2.\u6bd4\u8f83\u8fd0\u7b97\u7b26\uff1a\u67e5\u8be2\u5e93\u5b58\u5927\u4e8e\u5e73\u5747\u5e93\u5b58\u7684\u56fe\u4e66
SELECT bno,bname,stock
FROM book
WHERE stock > (
SELECT AVG(stock)
FROM book
);
3.EXISTS\uff1a\u67e5\u8be2\u5b58\u5728\u501f\u9605\u8bb0\u5f55\u7684\u8bfb\u8005
SELECT *
FROM reader r
WHERE EXISTS(
SELECT *
FROM borrow br
WHERE br.rno = r.rno
);
4.ANY\uff1a\u67e5\u8be2\u5e93\u5b58\u5927\u4e8e\u4efb\u610f\u4e00\u672c2018\u5e74\u51fa\u7248\u56fe\u4e66\u5e93\u5b58\u7684\u56fe\u4e66
SELECT bno,bname,stock
FROM book
WHERE stock > ANY(
SELECT stock
FROM book
WHERE pubyear = 2018
);
5.ALL\uff1a\u67e5\u8be2\u5e93\u5b58\u4e0d\u5c11\u4e8e\u6240\u6709\u56fe\u4e66\u5e93\u5b58\u7684\u56fe\u4e66
SELECT bno,bname,stock
FROM book
WHERE stock >= ALL(
SELECT stock
FROM book
);<\/pre>\n\n\n\n10.\u96c6\u5408\u67e5\u8be2<\/h2>\n\n\n\n1.UNION\uff1a\u5408\u5e76\u8bfb\u8005\u59d3\u540d\u548c\u4f5c\u8005\u59d3\u540d\u5e76\u53bb\u91cd
SELECT rname AS name
FROM reader
UNION
SELECT author AS name
FROM book;
2.UNION ALL\uff1a\u5408\u5e76\u8bfb\u8005\u59d3\u540d\u548c\u4f5c\u8005\u59d3\u540d\uff0c\u4e0d\u53bb\u91cd
SELECT rname AS name
FROM reader
UNION ALL
SELECT author AS name
FROM book;
3.\u6a21\u62df INTERSECT\uff1a\u67e5\u8be2\u501f\u8fc7\u4e66\u7684\u8bfb\u8005\u8bc1\u53f7
SELECT rno
FROM reader
WHERE rno IN(
SELECT rno
FROM borrow
);
4.\u6a21\u62df EXCEPT\uff1a\u67e5\u8be2\u6ca1\u6709\u501f\u4e66\u7684\u8bfb\u8005
SELECT rno,rname
FROM reader
WHERE rno NOT IN(
SELECT rno
FROM borrow
);<\/pre>\n\n\n\n11.\u89c6\u56fe\u64cd\u4f5c<\/h2>\n\n\n\n1.\u521b\u5efa\u672a\u5f52\u8fd8\u56fe\u4e66\u89c6\u56fe
CREATE VIEW v_unreturned AS
SELECT br.borrowid, r.rname, b.bname,
br.borrowdate, br.returndate
FROM borrow br
JOIN reader r ON br.rno = r.rno
JOIN book b ON br.bno = b.bno
WHERE br.actualdate IS NULL;
2.\u67e5\u8be2\u89c6\u56fe
SELECT * FROM v_unreturned;
3.\u521b\u5efa\u5b66\u751f\u8bfb\u8005\u89c6\u56fe\uff0c\u5e26 WITH CHECK OPTION
CREATE VIEW v_student_reader AS
SELECT *
FROM reader
WHERE dept LIKE '%\u5b66\u9662%'
WITH CHECK OPTION;
4.\u6d4b\u8bd5\u53ef\u66f4\u65b0\u89c6\u56fe
UPDATE v_student_reader
SET phone = '18800000000'
WHERE rno = 'R2024002';
\u8bf4\u660e\uff1a
\u8be5\u89c6\u56fe\u57fa\u4e8e\u5355\u8868 reader \u521b\u5efa\uff0c\u6ca1\u6709\u805a\u5408\u51fd\u6570\u3001\u5206\u7ec4\u548c\u8fde\u63a5\uff0c\u56e0\u6b64\u5c5e\u4e8e\u53ef\u66f4\u65b0\u89c6\u56fe\u3002
5.\u521b\u5efa\u4e0d\u53ef\u66f4\u65b0\u7684\u805a\u5408\u89c6\u56fe
CREATE VIEW v_press_count AS
SELECT press, COUNT(*) AS total
FROM book
GROUP BY press;
\u8bf4\u660e\uff1a
\u8be5\u89c6\u56fe\u4f7f\u7528\u4e86 GROUP BY \u548c COUNT \u805a\u5408\u51fd\u6570\uff0c\u56e0\u6b64\u4e00\u822c\u4e0d\u80fd\u76f4\u63a5\u66f4\u65b0\u3002
6.\u5220\u9664\u89c6\u56fe
DROP VIEW v_unreturned;
DROP VIEW v_student_reader;
DROP VIEW v_press_count;<\/pre>\n\n\n\n12.\u7d22\u5f15<\/h2>\n\n\n\n1.\u521b\u5efa\u666e\u901a\u7d22\u5f15
CREATE INDEX idx_book_bname
ON book(bname);
2.\u521b\u5efa\u552f\u4e00\u7d22\u5f15
CREATE UNIQUE INDEX idx_reader_phone
ON reader(phone);
3.\u521b\u5efa\u590d\u5408\u7d22\u5f15
CREATE INDEX idx_borrow_rno_bno
ON borrow(rno,bno);
\u67e5\u770b\u7d22\u5f15
SHOW INDEX FROM book;
SHOW INDEX FROM reader;
SHOW INDEX FROM borrow;
\u5220\u9664\u7d22\u5f15
DROP INDEX idx_book_bname ON book;
DROP INDEX idx_reader_phone ON reader;
DROP INDEX idx_borrow_rno_bno ON borrow;<\/pre>\n\n\n\n13.\u6570\u636e\u5b8c\u6574\u6027\u7ea6\u675f\u9a8c\u8bc1\u4e0e\u7ea7\u8054\u64cd\u4f5c<\/h2>\n\n\n\n1.\u5b9e\u4f53\u5b8c\u6574\u6027\u9a8c\u8bc1\uff1a\u4e3b\u952e\u4e0d\u80fd\u4e3a\u7a7a
INSERT INTO book(bno,bname,author,press,pubyear,stock)
VALUES(NULL,'\u6d4b\u8bd5\u4e66','\u6d4b\u8bd5\u4f5c\u8005','\u6d4b\u8bd5\u51fa\u7248\u793e',2020,1);
\u8bf4\u660e\uff1a
bno \u662f book \u8868\u4e3b\u952e\uff0c\u4e3b\u952e\u4e0d\u80fd\u4e3a\u7a7a\uff0c\u56e0\u6b64\u63d2\u5165\u5931\u8d25\u3002
2.\u53c2\u7167\u5b8c\u6574\u6027\u9a8c\u8bc1\uff1a\u63d2\u5165\u4e0d\u5b58\u5728\u7684\u56fe\u4e66\u7f16\u53f7
INSERT INTO borrow(rno,bno,borrowdate,returndate,actualdate)
VALUES('R2024001','B999','2025-05-01','2025-05-15',NULL);
\u8bf4\u660e\uff1a
B999 \u5728 book \u8868\u4e2d\u4e0d\u5b58\u5728\uff0cborrow.bno \u662f\u5916\u952e\uff0c\u56e0\u6b64\u8fdd\u53cd\u53c2\u7167\u5b8c\u6574\u6027\u3002
3.\u7528\u6237\u5b9a\u4e49\u5b8c\u6574\u6027\u9a8c\u8bc1\uff1a\u5e93\u5b58\u4e0d\u80fd\u5c0f\u4e8e0
UPDATE book
SET stock = -1
WHERE bno = 'B001';
\u8bf4\u660e\uff1a
stock \u5b57\u6bb5\u8bbe\u7f6e\u4e86 CHECK(stock>=0)\uff0c\u5e93\u5b58\u4e0d\u80fd\u4e3a\u8d1f\u6570\u3002
4.\u7528\u6237\u5b9a\u4e49\u5b8c\u6574\u6027\u9a8c\u8bc1\uff1a\u5e93\u5b58\u4e0d\u80fd\u5c0f\u4e8e0
UPDATE book
SET stock = -1
WHERE bno = 'B001';
\u8bf4\u660e\uff1a
stock \u5b57\u6bb5\u8bbe\u7f6e\u4e86 CHECK(stock>=0)\uff0c\u5e93\u5b58\u4e0d\u80fd\u4e3a\u8d1f\u6570\u3002
5.ON UPDATE CASCADE \u6d4b\u8bd5
UPDATE reader
SET rno = 'R2024999'
WHERE rno = 'R2024003';
SELECT * FROM borrow
WHERE rno = 'R2024999';
\u8bf4\u660e\uff1a
reader.rno \u66f4\u65b0\u540e\uff0cborrow \u8868\u4e2d\u5bf9\u5e94\u7684\u5916\u952e rno \u4f1a\u81ea\u52a8\u540c\u6b65\u66f4\u65b0\u3002<\/pre>\n\n\n\n14.\u89e6\u53d1\u5668<\/h2>\n\n\n\n\u51c6\u5907\uff1a\u5220\u9664\u65e7\u89e6\u53d1\u5668
DROP TRIGGER IF EXISTS trg_borrow_before_insert;
DROP TRIGGER IF EXISTS trg_return_after_update;
DROP TRIGGER IF EXISTS trg_reader_before_delete;
\u521b\u5efa\u5220\u9664\u8bfb\u8005\u65e5\u5fd7\u8868
CREATE TABLE reader_delete_log(
logid INT AUTO_INCREMENT PRIMARY KEY,
rno CHAR(12),
rname VARCHAR(20),
dept VARCHAR(40),
delete_time DATETIME DEFAULT CURRENT_TIMESTAMP
);
1.\u501f\u4e66\u65f6\u81ea\u52a8\u51cf\u5c11\u5e93\u5b58
DELIMITER \/\/
CREATE TRIGGER trg_borrow_before_insert
BEFORE INSERT ON borrow
FOR EACH ROW
BEGIN
DECLARE v_stock INT;
SELECT stock INTO v_stock
FROM book
WHERE bno = NEW.bno;
IF v_stock <= 0 THEN
SIGNAL SQLSTATE '45000'
SET MESSAGE_TEXT = '\u5e93\u5b58\u4e0d\u8db3\uff0c\u4e0d\u80fd\u501f\u4e66';
ELSE
UPDATE book
SET stock = stock - 1
WHERE bno = NEW.bno;
END IF;
END \/\/
DELIMITER ;
\u6d4b\u8bd5\uff1a
SELECT stock FROM book WHERE bno='B003';
INSERT INTO borrow(rno,bno,borrowdate,returndate,actualdate)
VALUES('R2024002','B003','2025-05-01','2025-05-15',NULL);
SELECT stock FROM book WHERE bno='B003';
2.\u8fd8\u4e66\u65f6\u81ea\u52a8\u589e\u52a0\u5e93\u5b58\u5e76\u8ba1\u7b97\u7f5a\u6b3e
DELIMITER \/\/
CREATE TRIGGER trg_return_after_update
AFTER UPDATE ON borrow
FOR EACH ROW
BEGIN
IF OLD.actualdate IS NULL AND NEW.actualdate IS NOT NULL THEN
UPDATE book
SET stock = stock + 1
WHERE bno = NEW.bno;
UPDATE borrow
SET fine =
CASE
WHEN NEW.actualdate > NEW.returndate
THEN DATEDIFF(NEW.actualdate, NEW.returndate) * 1
ELSE 0
END
WHERE borrowid = NEW.borrowid;
END IF;
END \/\/
DELIMITER ;
\u6d4b\u8bd5\uff1a
UPDATE borrow
SET actualdate = '2025-05-18'
WHERE rno='R2024002'
AND bno='B003'
AND borrowdate='2025-05-01';
SELECT * FROM borrow
WHERE rno='R2024002'
AND bno='B003';
SELECT stock FROM book WHERE bno='B003';
3.\u5220\u9664\u8bfb\u8005\u524d\u8bb0\u5f55\u65e5\u5fd7
DELIMITER \/\/
CREATE TRIGGER trg_reader_before_delete
BEFORE DELETE ON reader
FOR EACH ROW
BEGIN
INSERT INTO reader_delete_log(rno,rname,dept)
VALUES(OLD.rno, OLD.rname, OLD.dept);
END \/\/
DELIMITER ;
\u6d4b\u8bd5\uff1a
INSERT INTO reader
VALUES('R2024888','\u65e5\u5fd7\u6d4b\u8bd5','\u7537','\u6d4b\u8bd5\u5b66\u9662','\u65e0');
DELETE FROM reader
WHERE rno='R2024888';
SELECT * FROM reader_delete_log;<\/pre>\n\n\n\n15.\u6570\u636e\u5b89\u5168\u6027<\/h2>\n\n\n\n1.\u521b\u5efa\u7528\u6237\u5e76\u6388\u4e88\u67e5\u8be2\u6743\u9650
CREATE USER 'lib_user1'@'localhost'
IDENTIFIED BY '123456';
GRANT SELECT
ON library_db.book
TO 'lib_user1'@'localhost';
\u67e5\u770b\u6743\u9650\uff1a
SHOW GRANTS FOR 'lib_user1'@'localhost';
2.\u6388\u4e88\u6743\u9650\u5e76\u5141\u8bb8\u8f6c\u6388\u6743
GRANT SELECT, INSERT
ON library_db.reader
TO 'lib_user1'@'localhost'
WITH GRANT OPTION;
\u8bf4\u660e\uff1a
WITH GRANT OPTION \u8868\u793a\u8be5\u7528\u6237\u53ef\u4ee5\u5c06\u81ea\u5df1\u62e5\u6709\u7684\u6743\u9650\u518d\u6388\u4e88\u5176\u4ed6\u7528\u6237\u3002
3.\u56de\u6536\u6743\u9650
REVOKE INSERT
ON library_db.reader
FROM 'lib_user1'@'localhost';
4.\u521b\u5efa\u89d2\u8272\u5e76\u6388\u6743
CREATE ROLE 'reader_role';
GRANT SELECT
ON library_db.*
TO 'reader_role';
CREATE USER 'lib_user2'@'localhost'
IDENTIFIED BY '123456';
GRANT 'reader_role'
TO 'lib_user2'@'localhost';
SET DEFAULT ROLE 'reader_role'
TO 'lib_user2'@'localhost';<\/pre>\n\n\n\n16.\u89c6\u56fe\u4e0e\u6d3e\u751f\u8868<\/h2>\n\n\n\n1.\u5e26\u805a\u5408\u51fd\u6570\u7684\u89c6\u56fe\uff1a\u7edf\u8ba1\u6bcf\u4e2a\u8bfb\u8005\u501f\u9605\u6b21\u6570
CREATE VIEW v_reader_borrow_count AS
SELECT r.rno, r.rname, COUNT(br.borrowid) AS borrow_count
FROM reader r
LEFT JOIN borrow br
ON r.rno = br.rno
GROUP BY r.rno, r.rname;
\u67e5\u8be2\uff1a
SELECT * FROM v_reader_borrow_count;
2.\u6d3e\u751f\u8868\uff1a\u67e5\u8be2\u501f\u9605\u6b21\u6570\u5927\u4e8e1\u7684\u8bfb\u8005
SELECT *
FROM (
SELECT rno, COUNT(*) AS borrow_count
FROM borrow
GROUP BY rno
) AS t
WHERE t.borrow_count > 1;
3.WITH \u5b50\u53e5\u7edf\u8ba1\u6bcf\u4f4d\u8bfb\u8005\u501f\u9605\u6570\u91cf
WITH reader_count AS (
SELECT rno, COUNT(*) AS total
FROM borrow
GROUP BY rno
)
SELECT r.rno, r.rname, rc.total
FROM reader r
LEFT JOIN reader_count rc
ON r.rno = rc.rno;
4.WITH \u5b50\u53e5\uff1a\u67e5\u8be2\u672a\u5f52\u8fd8\u56fe\u4e66
WITH unreturned AS (
SELECT br.borrowid, r.rname, b.bname,
br.borrowdate, br.returndate
FROM borrow br
JOIN reader r ON br.rno = r.rno
JOIN book b ON br.bno = b.bno
WHERE br.actualdate IS NULL
)
SELECT * FROM unreturned;<\/pre>\n\n\n\n17.\u6269\u5c55\u601d\u8003<\/h2>\n\n\n\n\n- \u5982\u4f55\u5904\u7406\u5206\u7c7b\u5b9e\u4f53\u7684\u81ea\u5173\u8054\uff1f<\/li>\n<\/ol>\n\n\n\n
\u5206\u7c7b\u5b9e\u4f53\u5b58\u5728\u201c\u4e0a\u7ea7\u5206\u7c7b\u201d\u548c\u201c\u4e0b\u7ea7\u5206\u7c7b\u201d\u7684\u5173\u7cfb\uff0c\u56e0\u6b64\u53ef\u4ee5\u5728 category \u8868\u4e2d\u8bbe\u7f6e parentid \u5b57\u6bb5\u3002
category(
cid,
cname,
parentid
)
\u5176\u4e2d cid \u662f\u5206\u7c7b\u7f16\u53f7\uff0cparentid \u662f\u4e0a\u7ea7\u5206\u7c7b\u7f16\u53f7\uff0c\u540c\u65f6 parentid \u4e5f\u662f\u6307\u5411 category.cid \u7684\u5916\u952e\u3002
\u5982\u679c\u67d0\u5206\u7c7b\u6ca1\u6709\u4e0a\u7ea7\u5206\u7c7b\uff0c\u5219 parentid \u53ef\u4ee5\u4e3a\u7a7a\u3002
\u8fd9\u79cd\u8bbe\u8ba1\u53ef\u4ee5\u8868\u793a\u6811\u5f62\u7ed3\u6784\uff0c\u4f8b\u5982\uff1a
\u56fe\u4e66
\u251c\u2500\u2500 \u8ba1\u7b97\u673a
\u2502 \u251c\u2500\u2500 \u6570\u636e\u5e93
\u2502 \u2514\u2500\u2500 \u7f51\u7edc\u6280\u672f
\u2514\u2500\u2500 \u6587\u5b66
\u2514\u2500\u2500 \u79d1\u5e7b\u5c0f\u8bf4<\/pre>\n\n\n\n
\n\n\n\n2. \u501f\u9605\u5173\u7cfb\u662f\u5426\u53ef\u80fd\u5b58\u5728\u6570\u636e\u5197\u4f59\uff1f<\/h2>\n\n\n\n\u501f\u9605\u8868\u5982\u679c\u53ea\u4fdd\u5b58 rno\u3001bno\u3001borrowdate\u3001returndate\u3001actualdate \u7b49\u4fe1\u606f\uff0c\u5219\u5197\u4f59\u8f83\u5c11\u3002
\u4f46\u662f\u5982\u679c\u5728 borrow \u8868\u4e2d\u540c\u65f6\u4fdd\u5b58\u8bfb\u8005\u59d3\u540d rname\u3001\u56fe\u4e66\u540d\u79f0 bname\u3001\u51fa\u7248\u793e press \u7b49\u4fe1\u606f\uff0c\u5c31\u4f1a\u4ea7\u751f\u6570\u636e\u5197\u4f59\u3002
\u4f8b\u5982\uff1a
borrow(borrowid, rno, rname, bno, bname, borrowdate)
\u5176\u4e2d rname \u4f9d\u8d56 rno\uff0cbname \u4f9d\u8d56 bno\uff0c\u800c\u4e0d\u662f\u76f4\u63a5\u4f9d\u8d56 borrowid\uff0c\u4f1a\u4ea7\u751f\u4f20\u9012\u4f9d\u8d56\u3002
\u89c4\u8303\u5316\u65b9\u6848\uff1a
\u5c06\u8bfb\u8005\u4fe1\u606f\u4fdd\u5b58\u5728 reader \u8868\uff1b
\u5c06\u56fe\u4e66\u4fe1\u606f\u4fdd\u5b58\u5728 book \u8868\uff1b
borrow \u8868\u53ea\u4fdd\u5b58\u8bfb\u8005\u8bc1\u53f7\u548c\u56fe\u4e66\u7f16\u53f7\u4f5c\u4e3a\u5916\u952e\u3002<\/pre>\n\n\n\n
\n\n\n\n3. \u5982\u4f55\u9632\u6b62\u5e93\u5b58\u4e3a\u8d1f\u6570\uff1f<\/h2>\n\n\n\n\u53ef\u4ee5\u4ece\u4e24\u4e2a\u65b9\u9762\u9632\u6b62\u5e93\u5b58\u4e3a\u8d1f\u6570\uff1a
\u7b2c\u4e00\uff0c\u5728 book \u8868\u4e2d\u8bbe\u7f6e CHECK(stock >= 0) \u7ea6\u675f\uff0c\u4fdd\u8bc1\u5e93\u5b58\u4e0d\u80fd\u5c0f\u4e8e0\u3002
\u7b2c\u4e8c\uff0c\u5728\u501f\u4e66\u89e6\u53d1\u5668\u4e2d\u5224\u65ad\u5e93\u5b58\u6570\u91cf\u3002
\u5f53\u63d2\u5165 borrow \u501f\u9605\u8bb0\u5f55\u65f6\uff0c\u5148\u67e5\u8be2\u56fe\u4e66\u5e93\u5b58\u3002
\u5982\u679c\u5e93\u5b58\u5c0f\u4e8e\u7b49\u4e8e0\uff0c\u5219\u4f7f\u7528 SIGNAL \u629b\u51fa\u9519\u8bef\uff0c\u963b\u6b62\u501f\u4e66\u64cd\u4f5c\uff1b
\u5982\u679c\u5e93\u5b58\u5927\u4e8e0\uff0c\u5219\u5141\u8bb8\u501f\u9605\uff0c\u5e76\u81ea\u52a8\u5c06\u5e93\u5b58\u51cf1\u3002
\u8fd9\u6837\u53ef\u4ee5\u4fdd\u8bc1\u501f\u4e66\u65f6\u4e0d\u4f1a\u51fa\u73b0\u5e93\u5b58\u4e3a\u8d1f\u6570\u7684\u60c5\u51b5\u3002<\/pre>\n\n\n\n
\n\n\n\n4. \u9884\u7ea6\u56fe\u4e66\u529f\u80fd\u9700\u8981\u589e\u52a0\u54ea\u4e9b\u5b9e\u4f53\u548c\u5173\u7cfb\uff1f<\/h2>\n\n\n\n\u5982\u679c\u7cfb\u7edf\u652f\u6301\u9884\u7ea6\u56fe\u4e66\u529f\u80fd\uff0c\u53ef\u4ee5\u589e\u52a0 reservation \u9884\u7ea6\u8868\u3002
reservation(
reserveid,
rno,
bno,
reservedate,
status
)
\u5176\u4e2d\uff1a
reserveid \u8868\u793a\u9884\u7ea6\u7f16\u53f7\uff1b
rno \u662f\u8bfb\u8005\u8bc1\u53f7\uff0c\u5916\u952e\u5f15\u7528 reader.rno\uff1b
bno \u662f\u56fe\u4e66\u7f16\u53f7\uff0c\u5916\u952e\u5f15\u7528 book.bno\uff1b
reservedate \u8868\u793a\u9884\u7ea6\u65e5\u671f\uff1b
status \u8868\u793a\u9884\u7ea6\u72b6\u6001\uff0c\u5982\u201c\u9884\u7ea6\u4e2d\u201d\u201c\u5df2\u53d6\u6d88\u201d\u201c\u5df2\u5b8c\u6210\u201d\u3002
\u65b0\u589e\u5173\u7cfb\uff1a
\u4e00\u4e2a\u8bfb\u8005\u53ef\u4ee5\u9884\u7ea6\u591a\u672c\u56fe\u4e66\uff1b
\u4e00\u672c\u56fe\u4e66\u53ef\u4ee5\u88ab\u591a\u4e2a\u8bfb\u8005\u9884\u7ea6\uff1b
\u8bfb\u8005\u548c\u56fe\u4e66\u4e4b\u95f4\u901a\u8fc7 reservation \u8868\u5f62\u6210 m:n \u8054\u7cfb\u3002<\/pre>\n\n\n\n
\n\n\n\n5. \u4e3a\u4ec0\u4e48\u9075\u5faa\u6700\u5c0f\u6743\u9650\u539f\u5219\uff1f<\/h2>\n\n\n\n\u6700\u5c0f\u6743\u9650\u539f\u5219\u662f\u6307\u53ea\u7ed9\u7528\u6237\u5b8c\u6210\u5de5\u4f5c\u6240\u5fc5\u9700\u7684\u6743\u9650\uff0c\u4e0d\u6388\u4e88\u591a\u4f59\u6743\u9650\u3002
\u5728\u672c\u5b9e\u9a8c\u4e2d\uff0c\u5982\u679c\u67d0\u7528\u6237\u53ea\u8d1f\u8d23\u67e5\u8be2\u56fe\u4e66\u4fe1\u606f\uff0c\u5219\u53ea\u6388\u4e88 SELECT \u6743\u9650\u5373\u53ef\uff0c\u4e0d\u5e94\u8be5\u6388\u4e88 INSERT\u3001UPDATE\u3001DELETE \u7b49\u6743\u9650\u3002
\u4f8b\u5982\uff1a
GRANT SELECT ON library_db.book TO 'lib_user1'@'localhost';
\u8fd9\u6837\u53ef\u4ee5\u9632\u6b62\u7528\u6237\u8bef\u5220\u3001\u8bef\u6539\u6570\u636e\uff0c\u63d0\u9ad8\u6570\u636e\u5e93\u5b89\u5168\u6027\u3002
\u5982\u679c\u540e\u7eed\u4e0d\u518d\u9700\u8981\u67d0\u9879\u6743\u9650\uff0c\u8fd8\u53ef\u4ee5\u4f7f\u7528 REVOKE \u56de\u6536\u6743\u9650\u3002<\/pre>\n\n\n\n
\n\n\n\n6. \u5e76\u53d1\u501f\u9605\u5e93\u5b58\u4ec5\u52691\u672c\u7684\u56fe\u4e66\u4f1a\u4ea7\u751f\u4ec0\u4e48\u95ee\u9898\uff1f\u5982\u4f55\u89e3\u51b3\uff1f<\/h2>\n\n\n\n\u5f53\u591a\u7528\u6237\u540c\u65f6\u501f\u9605\u540c\u4e00\u672c\u5e93\u5b58\u4ec5\u52691\u672c\u7684\u56fe\u4e66\u65f6\uff0c\u53ef\u80fd\u51fa\u73b0\u8d85\u5356\u95ee\u9898\u3002
\u4f8b\u5982\u4e24\u4e2a\u7528\u6237\u540c\u65f6\u8bfb\u53d6\u5e93\u5b58 stock=1\uff0c\u90fd\u8ba4\u4e3a\u53ef\u4ee5\u501f\u9605\uff0c\u7136\u540e\u540c\u65f6\u63d2\u5165\u501f\u9605\u8bb0\u5f55\u5e76\u6267\u884c\u5e93\u5b58\u51cf1\uff0c\u6700\u7ec8\u53ef\u80fd\u5bfc\u81f4\u5e93\u5b58\u5f02\u5e38\u6216\u51fa\u73b0\u8d85\u989d\u501f\u9605\u3002
\u89e3\u51b3\u65b9\u6cd5\uff1a
1. \u4f7f\u7528\u4e8b\u52a1\u4fdd\u8bc1\u501f\u4e66\u64cd\u4f5c\u7684\u539f\u5b50\u6027\uff1b
2. \u4f7f\u7528 SELECT ... FOR UPDATE \u5bf9\u56fe\u4e66\u5e93\u5b58\u8bb0\u5f55\u52a0\u884c\u7ea7\u9501\uff1b
3. \u5728\u89e6\u53d1\u5668\u4e2d\u5224\u65ad\u5e93\u5b58\u662f\u5426\u5927\u4e8e0\uff1b
4. \u7ed9 stock \u5b57\u6bb5\u8bbe\u7f6e CHECK(stock >= 0) \u7ea6\u675f\u3002
\u793a\u4f8b\uff1a
START TRANSACTION;
SELECT stock
FROM book
WHERE bno='B001'
FOR UPDATE;
UPDATE book
SET stock = stock - 1
WHERE bno='B001'
AND stock > 0;
INSERT INTO borrow(rno,bno,borrowdate,returndate)
VALUES('R2024001','B001','2025-05-01','2025-05-15');
COMMIT;
\u8fd9\u6837\u53ef\u4ee5\u907f\u514d\u591a\u4e2a\u7528\u6237\u540c\u65f6\u4fee\u6539\u5e93\u5b58\u5bfc\u81f4\u6570\u636e\u4e0d\u4e00\u81f4\u3002<\/pre>\n\n\n\n
\n\n\n\n\u5b9e\u9a8c\u603b\u7ed3<\/h1>\n\n\n\n \u901a\u8fc7\u672c\u6b21\u56fe\u4e66\u501f\u9605\u7ba1\u7406\u7cfb\u7edf\u7efc\u5408\u5b9e\u9a8c\uff0c\u6211\u7cfb\u7edf\u5730\u5b8c\u6210\u4e86\u6570\u636e\u5e93\u8bbe\u8ba1\u4e0e\u5b9e\u73b0\u7684\u5168\u8fc7\u7a0b\u3002\u5b9e\u9a8c\u4ece\u9700\u6c42\u5206\u6790\u5f00\u59cb\uff0c\u9010\u6b65\u5b8c\u6210 E-R \u56fe\u8bbe\u8ba1\u3001\u5173\u7cfb\u6a21\u5f0f\u8f6c\u6362\u3001\u7269\u7406\u8868\u7ed3\u6784\u8bbe\u8ba1\u3001\u6570\u636e\u63d2\u5165\u3001\u67e5\u8be2\u64cd\u4f5c\u3001\u89c6\u56fe\u3001\u7d22\u5f15\u3001\u5b8c\u6574\u6027\u7ea6\u675f\u3001\u89e6\u53d1\u5668\u548c\u6743\u9650\u7ba1\u7406\u7b49\u5185\u5bb9\uff0c\u4f7f\u6211\u5bf9\u6570\u636e\u5e93\u5e94\u7528\u7cfb\u7edf\u7684\u8bbe\u8ba1\u6d41\u7a0b\u6709\u4e86\u66f4\u52a0\u5b8c\u6574\u7684\u8ba4\u8bc6\u3002
\u200b
\u5728\u5b9e\u9a8c\u8fc7\u7a0b\u4e2d\uff0c\u6211\u9996\u5148\u6839\u636e\u56fe\u4e66\u9986\u4e1a\u52a1\u9700\u6c42\u5206\u6790\u51fa\u56fe\u4e66\u3001\u8bfb\u8005\u3001\u501f\u9605\u3001\u51fa\u7248\u793e\u3001\u5206\u7c7b\u7b49\u5b9e\u4f53\uff0c\u5e76\u660e\u786e\u4e86\u5b83\u4eec\u4e4b\u95f4\u7684\u8054\u7cfb\u7c7b\u578b\u3002\u4f8b\u5982\uff0c\u51fa\u7248\u793e\u4e0e\u56fe\u4e66\u4e4b\u95f4\u662f\u4e00\u5bf9\u591a\u5173\u7cfb\uff0c\u5206\u7c7b\u4e0e\u56fe\u4e66\u4e4b\u95f4\u662f\u4e00\u5bf9\u591a\u5173\u7cfb\uff0c\u8bfb\u8005\u4e0e\u56fe\u4e66\u4e4b\u95f4\u901a\u8fc7\u501f\u9605\u8868\u5f62\u6210\u591a\u5bf9\u591a\u5173\u7cfb\u3002\u901a\u8fc7 E-R \u56fe\u8bbe\u8ba1\uff0c\u6211\u8fdb\u4e00\u6b65\u7406\u89e3\u4e86\u6982\u5ff5\u7ed3\u6784\u8bbe\u8ba1\u5728\u6570\u636e\u5e93\u5f00\u53d1\u4e2d\u7684\u91cd\u8981\u4f5c\u7528\u3002
\u200b
\u5728\u903b\u8f91\u7ed3\u6784\u8bbe\u8ba1\u9636\u6bb5\uff0c\u6211\u5c06 E-R \u56fe\u8f6c\u6362\u4e3a\u5173\u7cfb\u6a21\u5f0f\uff0c\u5e76\u5206\u6790\u5404\u8868\u662f\u5426\u6ee1\u8db3\u7b2c\u4e09\u8303\u5f0f\u3002\u901a\u8fc7\u89c4\u8303\u5316\u8bbe\u8ba1\uff0c\u907f\u514d\u4e86\u5728\u501f\u9605\u8868\u4e2d\u91cd\u590d\u4fdd\u5b58\u8bfb\u8005\u59d3\u540d\u3001\u56fe\u4e66\u540d\u79f0\u7b49\u4fe1\u606f\uff0c\u51cf\u5c11\u4e86\u6570\u636e\u5197\u4f59\uff0c\u63d0\u9ad8\u4e86\u6570\u636e\u4e00\u81f4\u6027\u3002\u5728\u7269\u7406\u8bbe\u8ba1\u9636\u6bb5\uff0c\u6211\u4f7f\u7528 SQL \u521b\u5efa\u6570\u636e\u5e93\u548c\u6570\u636e\u8868\uff0c\u8bbe\u7f6e\u4e86\u4e3b\u952e\u3001\u5916\u952e\u3001\u975e\u7a7a\u3001\u9ed8\u8ba4\u503c\u548c CHECK \u7ea6\u675f\uff0c\u5bf9\u5b9e\u4f53\u5b8c\u6574\u6027\u3001\u53c2\u7167\u5b8c\u6574\u6027\u548c\u7528\u6237\u5b9a\u4e49\u5b8c\u6574\u6027\u6709\u4e86\u66f4\u6df1\u523b\u7684\u7406\u89e3\u3002
\u200b
\u5728\u6570\u636e\u64cd\u4f5c\u90e8\u5206\uff0c\u6211\u7ec3\u4e60\u4e86 INSERT\u3001UPDATE\u3001DELETE \u548c SELECT \u8bed\u53e5\uff0c\u5e76\u5b8c\u6210\u4e86\u57fa\u7840\u67e5\u8be2\u3001\u805a\u5408\u67e5\u8be2\u3001\u591a\u8868\u8fde\u63a5\u67e5\u8be2\u3001\u5d4c\u5957\u67e5\u8be2\u548c\u96c6\u5408\u67e5\u8be2\u7b49\u5185\u5bb9\u3002\u901a\u8fc7\u8fd9\u4e9b\u7ec3\u4e60\uff0c\u6211\u638c\u63e1\u4e86 SQL \u67e5\u8be2\u8bed\u53e5\u7684\u5e38\u89c1\u5199\u6cd5\uff0c\u5c24\u5176\u662f\u591a\u8868\u8fde\u63a5\u548c\u5d4c\u5957\u67e5\u8be2\u7684\u4f7f\u7528\u65b9\u6cd5\u3002\u5b9e\u9a8c\u4e2d\u8fd8\u521b\u5efa\u4e86\u89c6\u56fe\u548c\u7d22\u5f15\uff0c\u7406\u89e3\u4e86\u89c6\u56fe\u53ef\u4ee5\u7b80\u5316\u590d\u6742\u67e5\u8be2\uff0c\u7d22\u5f15\u53ef\u4ee5\u63d0\u9ad8\u67e5\u8be2\u6548\u7387\uff0c\u4f46\u4e5f\u4f1a\u589e\u52a0\u7ef4\u62a4\u6210\u672c\u3002
\u200b
\u5728\u89e6\u53d1\u5668\u90e8\u5206\uff0c\u6211\u5b9e\u73b0\u4e86\u501f\u4e66\u81ea\u52a8\u51cf\u5c11\u5e93\u5b58\u3001\u8fd8\u4e66\u81ea\u52a8\u589e\u52a0\u5e93\u5b58\u5e76\u8ba1\u7b97\u7f5a\u6b3e\u3001\u5220\u9664\u8bfb\u8005\u524d\u8bb0\u5f55\u65e5\u5fd7\u7b49\u529f\u80fd\u3002\u901a\u8fc7\u89e6\u53d1\u5668\u5b9e\u9a8c\uff0c\u6211\u8ba4\u8bc6\u5230\u6570\u636e\u5e93\u4e0d\u4ec5\u53ef\u4ee5\u5b58\u50a8\u6570\u636e\uff0c\u8fd8\u53ef\u4ee5\u5728\u7279\u5b9a\u64cd\u4f5c\u53d1\u751f\u65f6\u81ea\u52a8\u6267\u884c\u4e00\u4e9b\u4e1a\u52a1\u903b\u8f91\u3002\u5b9e\u9a8c\u8fc7\u7a0b\u4e2d\u4e5f\u9047\u5230\u4e86\u4e00\u4e9b\u95ee\u9898\uff0c\u4f8b\u5982\u5916\u952e\u7ea6\u675f\u5bfc\u81f4\u6570\u636e\u65e0\u6cd5\u5220\u9664\u3001CHECK \u7ea6\u675f\u63d2\u5165\u5931\u8d25\u3001\u89e6\u53d1\u5668\u8bed\u6cd5\u9519\u8bef\u7b49\u3002\u901a\u8fc7\u67e5\u770b\u9519\u8bef\u4fe1\u606f\u3001\u4fee\u6539 SQL \u8bed\u53e5\u548c\u53cd\u590d\u6d4b\u8bd5\uff0c\u6700\u7ec8\u89e3\u51b3\u4e86\u8fd9\u4e9b\u95ee\u9898\u3002
\u200b
\u901a\u8fc7\u672c\u6b21\u5b9e\u9a8c\uff0c\u6211\u4e0d\u4ec5\u5de9\u56fa\u4e86\u6570\u636e\u5e93\u7406\u8bba\u77e5\u8bc6\uff0c\u4e5f\u63d0\u9ad8\u4e86 SQL \u7f16\u5199\u80fd\u529b\u548c\u6570\u636e\u5e93\u8c03\u8bd5\u80fd\u529b\u3002\u4eca\u540e\u5728\u8bbe\u8ba1\u6570\u636e\u5e93\u7cfb\u7edf<\/pre>\n","protected":false},"excerpt":{"rendered":"\u6570\u636e\u5e93\u7efc\u5408\u5b9e\u9a8c 1.\u9700\u6c42\u5206\u6790 \u67d0\u5927\u578b\u56fe\u4e66\u9986\u9700\u8981\u5f00\u53d1\u4e00\u5957\u6570\u5b57\u5316\u501f\u9605\u7ba1\u7406\u7cfb\u7edf\uff0c\u4e3b\u8981\u4e1a\u52a1\u9700\u6c42\u5982\u4e0b\uff1a \u56fe\u4e66\u4fe1\u606f\uff1a\u8bb0\u5f55\u56fe […]<\/p>\n","protected":false},"author":1,"featured_media":448,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[9],"tags":[],"class_list":["post-446","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-wenzhang"],"_links":{"self":[{"href":"https:\/\/fg2025.cn\/index.php\/wp-json\/wp\/v2\/posts\/446","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/fg2025.cn\/index.php\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/fg2025.cn\/index.php\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/fg2025.cn\/index.php\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/fg2025.cn\/index.php\/wp-json\/wp\/v2\/comments?post=446"}],"version-history":[{"count":0,"href":"https:\/\/fg2025.cn\/index.php\/wp-json\/wp\/v2\/posts\/446\/revisions"}],"wp:attachment":[{"href":"https:\/\/fg2025.cn\/index.php\/wp-json\/wp\/v2\/media?parent=446"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/fg2025.cn\/index.php\/wp-json\/wp\/v2\/categories?post=446"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/fg2025.cn\/index.php\/wp-json\/wp\/v2\/tags?post=446"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}
SELECT *
FROM reader
WHERE rno IN(
SELECT rno FROM borrow
);
2.\u6bd4\u8f83\u8fd0\u7b97\u7b26\uff1a\u67e5\u8be2\u5e93\u5b58\u5927\u4e8e\u5e73\u5747\u5e93\u5b58\u7684\u56fe\u4e66
SELECT bno,bname,stock
FROM book
WHERE stock > (
SELECT AVG(stock)
FROM book
);
3.EXISTS\uff1a\u67e5\u8be2\u5b58\u5728\u501f\u9605\u8bb0\u5f55\u7684\u8bfb\u8005
SELECT *
FROM reader r
WHERE EXISTS(
SELECT *
FROM borrow br
WHERE br.rno = r.rno
);
4.ANY\uff1a\u67e5\u8be2\u5e93\u5b58\u5927\u4e8e\u4efb\u610f\u4e00\u672c2018\u5e74\u51fa\u7248\u56fe\u4e66\u5e93\u5b58\u7684\u56fe\u4e66
SELECT bno,bname,stock
FROM book
WHERE stock > ANY(
SELECT stock
FROM book
WHERE pubyear = 2018
);
5.ALL\uff1a\u67e5\u8be2\u5e93\u5b58\u4e0d\u5c11\u4e8e\u6240\u6709\u56fe\u4e66\u5e93\u5b58\u7684\u56fe\u4e66
SELECT bno,bname,stock
FROM book
WHERE stock >= ALL(
SELECT stock
FROM book
);<\/pre>\n\n\n\n
10.\u96c6\u5408\u67e5\u8be2<\/h2>\n\n\n\n1.UNION\uff1a\u5408\u5e76\u8bfb\u8005\u59d3\u540d\u548c\u4f5c\u8005\u59d3\u540d\u5e76\u53bb\u91cd
SELECT rname AS name
FROM reader
UNION
SELECT author AS name
FROM book;
2.UNION ALL\uff1a\u5408\u5e76\u8bfb\u8005\u59d3\u540d\u548c\u4f5c\u8005\u59d3\u540d\uff0c\u4e0d\u53bb\u91cd
SELECT rname AS name
FROM reader
UNION ALL
SELECT author AS name
FROM book;
3.\u6a21\u62df INTERSECT\uff1a\u67e5\u8be2\u501f\u8fc7\u4e66\u7684\u8bfb\u8005\u8bc1\u53f7
SELECT rno
FROM reader
WHERE rno IN(
SELECT rno
FROM borrow
);
4.\u6a21\u62df EXCEPT\uff1a\u67e5\u8be2\u6ca1\u6709\u501f\u4e66\u7684\u8bfb\u8005
SELECT rno,rname
FROM reader
WHERE rno NOT IN(
SELECT rno
FROM borrow
);<\/pre>\n\n\n\n11.\u89c6\u56fe\u64cd\u4f5c<\/h2>\n\n\n\n1.\u521b\u5efa\u672a\u5f52\u8fd8\u56fe\u4e66\u89c6\u56fe
CREATE VIEW v_unreturned AS
SELECT br.borrowid, r.rname, b.bname,
br.borrowdate, br.returndate
FROM borrow br
JOIN reader r ON br.rno = r.rno
JOIN book b ON br.bno = b.bno
WHERE br.actualdate IS NULL;
2.\u67e5\u8be2\u89c6\u56fe
SELECT * FROM v_unreturned;
3.\u521b\u5efa\u5b66\u751f\u8bfb\u8005\u89c6\u56fe\uff0c\u5e26 WITH CHECK OPTION
CREATE VIEW v_student_reader AS
SELECT *
FROM reader
WHERE dept LIKE '%\u5b66\u9662%'
WITH CHECK OPTION;
4.\u6d4b\u8bd5\u53ef\u66f4\u65b0\u89c6\u56fe
UPDATE v_student_reader
SET phone = '18800000000'
WHERE rno = 'R2024002';
\u8bf4\u660e\uff1a
\u8be5\u89c6\u56fe\u57fa\u4e8e\u5355\u8868 reader \u521b\u5efa\uff0c\u6ca1\u6709\u805a\u5408\u51fd\u6570\u3001\u5206\u7ec4\u548c\u8fde\u63a5\uff0c\u56e0\u6b64\u5c5e\u4e8e\u53ef\u66f4\u65b0\u89c6\u56fe\u3002
5.\u521b\u5efa\u4e0d\u53ef\u66f4\u65b0\u7684\u805a\u5408\u89c6\u56fe
CREATE VIEW v_press_count AS
SELECT press, COUNT(*) AS total
FROM book
GROUP BY press;
\u8bf4\u660e\uff1a
\u8be5\u89c6\u56fe\u4f7f\u7528\u4e86 GROUP BY \u548c COUNT \u805a\u5408\u51fd\u6570\uff0c\u56e0\u6b64\u4e00\u822c\u4e0d\u80fd\u76f4\u63a5\u66f4\u65b0\u3002
6.\u5220\u9664\u89c6\u56fe
DROP VIEW v_unreturned;
DROP VIEW v_student_reader;
DROP VIEW v_press_count;<\/pre>\n\n\n\n12.\u7d22\u5f15<\/h2>\n\n\n\n1.\u521b\u5efa\u666e\u901a\u7d22\u5f15
CREATE INDEX idx_book_bname
ON book(bname);
2.\u521b\u5efa\u552f\u4e00\u7d22\u5f15
CREATE UNIQUE INDEX idx_reader_phone
ON reader(phone);
3.\u521b\u5efa\u590d\u5408\u7d22\u5f15
CREATE INDEX idx_borrow_rno_bno
ON borrow(rno,bno);
\u67e5\u770b\u7d22\u5f15
SHOW INDEX FROM book;
SHOW INDEX FROM reader;
SHOW INDEX FROM borrow;
\u5220\u9664\u7d22\u5f15
DROP INDEX idx_book_bname ON book;
DROP INDEX idx_reader_phone ON reader;
DROP INDEX idx_borrow_rno_bno ON borrow;<\/pre>\n\n\n\n13.\u6570\u636e\u5b8c\u6574\u6027\u7ea6\u675f\u9a8c\u8bc1\u4e0e\u7ea7\u8054\u64cd\u4f5c<\/h2>\n\n\n\n1.\u5b9e\u4f53\u5b8c\u6574\u6027\u9a8c\u8bc1\uff1a\u4e3b\u952e\u4e0d\u80fd\u4e3a\u7a7a
INSERT INTO book(bno,bname,author,press,pubyear,stock)
VALUES(NULL,'\u6d4b\u8bd5\u4e66','\u6d4b\u8bd5\u4f5c\u8005','\u6d4b\u8bd5\u51fa\u7248\u793e',2020,1);
\u8bf4\u660e\uff1a
bno \u662f book \u8868\u4e3b\u952e\uff0c\u4e3b\u952e\u4e0d\u80fd\u4e3a\u7a7a\uff0c\u56e0\u6b64\u63d2\u5165\u5931\u8d25\u3002
2.\u53c2\u7167\u5b8c\u6574\u6027\u9a8c\u8bc1\uff1a\u63d2\u5165\u4e0d\u5b58\u5728\u7684\u56fe\u4e66\u7f16\u53f7
INSERT INTO borrow(rno,bno,borrowdate,returndate,actualdate)
VALUES('R2024001','B999','2025-05-01','2025-05-15',NULL);
\u8bf4\u660e\uff1a
B999 \u5728 book \u8868\u4e2d\u4e0d\u5b58\u5728\uff0cborrow.bno \u662f\u5916\u952e\uff0c\u56e0\u6b64\u8fdd\u53cd\u53c2\u7167\u5b8c\u6574\u6027\u3002
3.\u7528\u6237\u5b9a\u4e49\u5b8c\u6574\u6027\u9a8c\u8bc1\uff1a\u5e93\u5b58\u4e0d\u80fd\u5c0f\u4e8e0
UPDATE book
SET stock = -1
WHERE bno = 'B001';
\u8bf4\u660e\uff1a
stock \u5b57\u6bb5\u8bbe\u7f6e\u4e86 CHECK(stock>=0)\uff0c\u5e93\u5b58\u4e0d\u80fd\u4e3a\u8d1f\u6570\u3002
4.\u7528\u6237\u5b9a\u4e49\u5b8c\u6574\u6027\u9a8c\u8bc1\uff1a\u5e93\u5b58\u4e0d\u80fd\u5c0f\u4e8e0
UPDATE book
SET stock = -1
WHERE bno = 'B001';
\u8bf4\u660e\uff1a
stock \u5b57\u6bb5\u8bbe\u7f6e\u4e86 CHECK(stock>=0)\uff0c\u5e93\u5b58\u4e0d\u80fd\u4e3a\u8d1f\u6570\u3002
5.ON UPDATE CASCADE \u6d4b\u8bd5
UPDATE reader
SET rno = 'R2024999'
WHERE rno = 'R2024003';
SELECT * FROM borrow
WHERE rno = 'R2024999';
\u8bf4\u660e\uff1a
reader.rno \u66f4\u65b0\u540e\uff0cborrow \u8868\u4e2d\u5bf9\u5e94\u7684\u5916\u952e rno \u4f1a\u81ea\u52a8\u540c\u6b65\u66f4\u65b0\u3002<\/pre>\n\n\n\n14.\u89e6\u53d1\u5668<\/h2>\n\n\n\n\u51c6\u5907\uff1a\u5220\u9664\u65e7\u89e6\u53d1\u5668
DROP TRIGGER IF EXISTS trg_borrow_before_insert;
DROP TRIGGER IF EXISTS trg_return_after_update;
DROP TRIGGER IF EXISTS trg_reader_before_delete;
\u521b\u5efa\u5220\u9664\u8bfb\u8005\u65e5\u5fd7\u8868
CREATE TABLE reader_delete_log(
logid INT AUTO_INCREMENT PRIMARY KEY,
rno CHAR(12),
rname VARCHAR(20),
dept VARCHAR(40),
delete_time DATETIME DEFAULT CURRENT_TIMESTAMP
);
1.\u501f\u4e66\u65f6\u81ea\u52a8\u51cf\u5c11\u5e93\u5b58
DELIMITER \/\/
CREATE TRIGGER trg_borrow_before_insert
BEFORE INSERT ON borrow
FOR EACH ROW
BEGIN
DECLARE v_stock INT;
SELECT stock INTO v_stock
FROM book
WHERE bno = NEW.bno;
IF v_stock <= 0 THEN
SIGNAL SQLSTATE '45000'
SET MESSAGE_TEXT = '\u5e93\u5b58\u4e0d\u8db3\uff0c\u4e0d\u80fd\u501f\u4e66';
ELSE
UPDATE book
SET stock = stock - 1
WHERE bno = NEW.bno;
END IF;
END \/\/
DELIMITER ;
\u6d4b\u8bd5\uff1a
SELECT stock FROM book WHERE bno='B003';
INSERT INTO borrow(rno,bno,borrowdate,returndate,actualdate)
VALUES('R2024002','B003','2025-05-01','2025-05-15',NULL);
SELECT stock FROM book WHERE bno='B003';
2.\u8fd8\u4e66\u65f6\u81ea\u52a8\u589e\u52a0\u5e93\u5b58\u5e76\u8ba1\u7b97\u7f5a\u6b3e
DELIMITER \/\/
CREATE TRIGGER trg_return_after_update
AFTER UPDATE ON borrow
FOR EACH ROW
BEGIN
IF OLD.actualdate IS NULL AND NEW.actualdate IS NOT NULL THEN
UPDATE book
SET stock = stock + 1
WHERE bno = NEW.bno;
UPDATE borrow
SET fine =
CASE
WHEN NEW.actualdate > NEW.returndate
THEN DATEDIFF(NEW.actualdate, NEW.returndate) * 1
ELSE 0
END
WHERE borrowid = NEW.borrowid;
END IF;
END \/\/
DELIMITER ;
\u6d4b\u8bd5\uff1a
UPDATE borrow
SET actualdate = '2025-05-18'
WHERE rno='R2024002'
AND bno='B003'
AND borrowdate='2025-05-01';
SELECT * FROM borrow
WHERE rno='R2024002'
AND bno='B003';
SELECT stock FROM book WHERE bno='B003';
3.\u5220\u9664\u8bfb\u8005\u524d\u8bb0\u5f55\u65e5\u5fd7
DELIMITER \/\/
CREATE TRIGGER trg_reader_before_delete
BEFORE DELETE ON reader
FOR EACH ROW
BEGIN
INSERT INTO reader_delete_log(rno,rname,dept)
VALUES(OLD.rno, OLD.rname, OLD.dept);
END \/\/
DELIMITER ;
\u6d4b\u8bd5\uff1a
INSERT INTO reader
VALUES('R2024888','\u65e5\u5fd7\u6d4b\u8bd5','\u7537','\u6d4b\u8bd5\u5b66\u9662','\u65e0');
DELETE FROM reader
WHERE rno='R2024888';
SELECT * FROM reader_delete_log;<\/pre>\n\n\n\n15.\u6570\u636e\u5b89\u5168\u6027<\/h2>\n\n\n\n1.\u521b\u5efa\u7528\u6237\u5e76\u6388\u4e88\u67e5\u8be2\u6743\u9650
CREATE USER 'lib_user1'@'localhost'
IDENTIFIED BY '123456';
GRANT SELECT
ON library_db.book
TO 'lib_user1'@'localhost';
\u67e5\u770b\u6743\u9650\uff1a
SHOW GRANTS FOR 'lib_user1'@'localhost';
2.\u6388\u4e88\u6743\u9650\u5e76\u5141\u8bb8\u8f6c\u6388\u6743
GRANT SELECT, INSERT
ON library_db.reader
TO 'lib_user1'@'localhost'
WITH GRANT OPTION;
\u8bf4\u660e\uff1a
WITH GRANT OPTION \u8868\u793a\u8be5\u7528\u6237\u53ef\u4ee5\u5c06\u81ea\u5df1\u62e5\u6709\u7684\u6743\u9650\u518d\u6388\u4e88\u5176\u4ed6\u7528\u6237\u3002
3.\u56de\u6536\u6743\u9650
REVOKE INSERT
ON library_db.reader
FROM 'lib_user1'@'localhost';
4.\u521b\u5efa\u89d2\u8272\u5e76\u6388\u6743
CREATE ROLE 'reader_role';
GRANT SELECT
ON library_db.*
TO 'reader_role';
CREATE USER 'lib_user2'@'localhost'
IDENTIFIED BY '123456';
GRANT 'reader_role'
TO 'lib_user2'@'localhost';
SET DEFAULT ROLE 'reader_role'
TO 'lib_user2'@'localhost';<\/pre>\n\n\n\n16.\u89c6\u56fe\u4e0e\u6d3e\u751f\u8868<\/h2>\n\n\n\n1.\u5e26\u805a\u5408\u51fd\u6570\u7684\u89c6\u56fe\uff1a\u7edf\u8ba1\u6bcf\u4e2a\u8bfb\u8005\u501f\u9605\u6b21\u6570
CREATE VIEW v_reader_borrow_count AS
SELECT r.rno, r.rname, COUNT(br.borrowid) AS borrow_count
FROM reader r
LEFT JOIN borrow br
ON r.rno = br.rno
GROUP BY r.rno, r.rname;
\u67e5\u8be2\uff1a
SELECT * FROM v_reader_borrow_count;
2.\u6d3e\u751f\u8868\uff1a\u67e5\u8be2\u501f\u9605\u6b21\u6570\u5927\u4e8e1\u7684\u8bfb\u8005
SELECT *
FROM (
SELECT rno, COUNT(*) AS borrow_count
FROM borrow
GROUP BY rno
) AS t
WHERE t.borrow_count > 1;
3.WITH \u5b50\u53e5\u7edf\u8ba1\u6bcf\u4f4d\u8bfb\u8005\u501f\u9605\u6570\u91cf
WITH reader_count AS (
SELECT rno, COUNT(*) AS total
FROM borrow
GROUP BY rno
)
SELECT r.rno, r.rname, rc.total
FROM reader r
LEFT JOIN reader_count rc
ON r.rno = rc.rno;
4.WITH \u5b50\u53e5\uff1a\u67e5\u8be2\u672a\u5f52\u8fd8\u56fe\u4e66
WITH unreturned AS (
SELECT br.borrowid, r.rname, b.bname,
br.borrowdate, br.returndate
FROM borrow br
JOIN reader r ON br.rno = r.rno
JOIN book b ON br.bno = b.bno
WHERE br.actualdate IS NULL
)
SELECT * FROM unreturned;<\/pre>\n\n\n\n17.\u6269\u5c55\u601d\u8003<\/h2>\n\n\n\n\n- \u5982\u4f55\u5904\u7406\u5206\u7c7b\u5b9e\u4f53\u7684\u81ea\u5173\u8054\uff1f<\/li>\n<\/ol>\n\n\n\n
\u5206\u7c7b\u5b9e\u4f53\u5b58\u5728\u201c\u4e0a\u7ea7\u5206\u7c7b\u201d\u548c\u201c\u4e0b\u7ea7\u5206\u7c7b\u201d\u7684\u5173\u7cfb\uff0c\u56e0\u6b64\u53ef\u4ee5\u5728 category \u8868\u4e2d\u8bbe\u7f6e parentid \u5b57\u6bb5\u3002
category(
cid,
cname,
parentid
)
\u5176\u4e2d cid \u662f\u5206\u7c7b\u7f16\u53f7\uff0cparentid \u662f\u4e0a\u7ea7\u5206\u7c7b\u7f16\u53f7\uff0c\u540c\u65f6 parentid \u4e5f\u662f\u6307\u5411 category.cid \u7684\u5916\u952e\u3002
\u5982\u679c\u67d0\u5206\u7c7b\u6ca1\u6709\u4e0a\u7ea7\u5206\u7c7b\uff0c\u5219 parentid \u53ef\u4ee5\u4e3a\u7a7a\u3002
\u8fd9\u79cd\u8bbe\u8ba1\u53ef\u4ee5\u8868\u793a\u6811\u5f62\u7ed3\u6784\uff0c\u4f8b\u5982\uff1a
\u56fe\u4e66
\u251c\u2500\u2500 \u8ba1\u7b97\u673a
\u2502 \u251c\u2500\u2500 \u6570\u636e\u5e93
\u2502 \u2514\u2500\u2500 \u7f51\u7edc\u6280\u672f
\u2514\u2500\u2500 \u6587\u5b66
\u2514\u2500\u2500 \u79d1\u5e7b\u5c0f\u8bf4<\/pre>\n\n\n\n
\n\n\n\n2. \u501f\u9605\u5173\u7cfb\u662f\u5426\u53ef\u80fd\u5b58\u5728\u6570\u636e\u5197\u4f59\uff1f<\/h2>\n\n\n\n\u501f\u9605\u8868\u5982\u679c\u53ea\u4fdd\u5b58 rno\u3001bno\u3001borrowdate\u3001returndate\u3001actualdate \u7b49\u4fe1\u606f\uff0c\u5219\u5197\u4f59\u8f83\u5c11\u3002
\u4f46\u662f\u5982\u679c\u5728 borrow \u8868\u4e2d\u540c\u65f6\u4fdd\u5b58\u8bfb\u8005\u59d3\u540d rname\u3001\u56fe\u4e66\u540d\u79f0 bname\u3001\u51fa\u7248\u793e press \u7b49\u4fe1\u606f\uff0c\u5c31\u4f1a\u4ea7\u751f\u6570\u636e\u5197\u4f59\u3002
\u4f8b\u5982\uff1a
borrow(borrowid, rno, rname, bno, bname, borrowdate)
\u5176\u4e2d rname \u4f9d\u8d56 rno\uff0cbname \u4f9d\u8d56 bno\uff0c\u800c\u4e0d\u662f\u76f4\u63a5\u4f9d\u8d56 borrowid\uff0c\u4f1a\u4ea7\u751f\u4f20\u9012\u4f9d\u8d56\u3002
\u89c4\u8303\u5316\u65b9\u6848\uff1a
\u5c06\u8bfb\u8005\u4fe1\u606f\u4fdd\u5b58\u5728 reader \u8868\uff1b
\u5c06\u56fe\u4e66\u4fe1\u606f\u4fdd\u5b58\u5728 book \u8868\uff1b
borrow \u8868\u53ea\u4fdd\u5b58\u8bfb\u8005\u8bc1\u53f7\u548c\u56fe\u4e66\u7f16\u53f7\u4f5c\u4e3a\u5916\u952e\u3002<\/pre>\n\n\n\n
\n\n\n\n3. \u5982\u4f55\u9632\u6b62\u5e93\u5b58\u4e3a\u8d1f\u6570\uff1f<\/h2>\n\n\n\n\u53ef\u4ee5\u4ece\u4e24\u4e2a\u65b9\u9762\u9632\u6b62\u5e93\u5b58\u4e3a\u8d1f\u6570\uff1a
\u7b2c\u4e00\uff0c\u5728 book \u8868\u4e2d\u8bbe\u7f6e CHECK(stock >= 0) \u7ea6\u675f\uff0c\u4fdd\u8bc1\u5e93\u5b58\u4e0d\u80fd\u5c0f\u4e8e0\u3002
\u7b2c\u4e8c\uff0c\u5728\u501f\u4e66\u89e6\u53d1\u5668\u4e2d\u5224\u65ad\u5e93\u5b58\u6570\u91cf\u3002
\u5f53\u63d2\u5165 borrow \u501f\u9605\u8bb0\u5f55\u65f6\uff0c\u5148\u67e5\u8be2\u56fe\u4e66\u5e93\u5b58\u3002
\u5982\u679c\u5e93\u5b58\u5c0f\u4e8e\u7b49\u4e8e0\uff0c\u5219\u4f7f\u7528 SIGNAL \u629b\u51fa\u9519\u8bef\uff0c\u963b\u6b62\u501f\u4e66\u64cd\u4f5c\uff1b
\u5982\u679c\u5e93\u5b58\u5927\u4e8e0\uff0c\u5219\u5141\u8bb8\u501f\u9605\uff0c\u5e76\u81ea\u52a8\u5c06\u5e93\u5b58\u51cf1\u3002
\u8fd9\u6837\u53ef\u4ee5\u4fdd\u8bc1\u501f\u4e66\u65f6\u4e0d\u4f1a\u51fa\u73b0\u5e93\u5b58\u4e3a\u8d1f\u6570\u7684\u60c5\u51b5\u3002<\/pre>\n\n\n\n
\n\n\n\n4. \u9884\u7ea6\u56fe\u4e66\u529f\u80fd\u9700\u8981\u589e\u52a0\u54ea\u4e9b\u5b9e\u4f53\u548c\u5173\u7cfb\uff1f<\/h2>\n\n\n\n\u5982\u679c\u7cfb\u7edf\u652f\u6301\u9884\u7ea6\u56fe\u4e66\u529f\u80fd\uff0c\u53ef\u4ee5\u589e\u52a0 reservation \u9884\u7ea6\u8868\u3002
reservation(
reserveid,
rno,
bno,
reservedate,
status
)
\u5176\u4e2d\uff1a
reserveid \u8868\u793a\u9884\u7ea6\u7f16\u53f7\uff1b
rno \u662f\u8bfb\u8005\u8bc1\u53f7\uff0c\u5916\u952e\u5f15\u7528 reader.rno\uff1b
bno \u662f\u56fe\u4e66\u7f16\u53f7\uff0c\u5916\u952e\u5f15\u7528 book.bno\uff1b
reservedate \u8868\u793a\u9884\u7ea6\u65e5\u671f\uff1b
status \u8868\u793a\u9884\u7ea6\u72b6\u6001\uff0c\u5982\u201c\u9884\u7ea6\u4e2d\u201d\u201c\u5df2\u53d6\u6d88\u201d\u201c\u5df2\u5b8c\u6210\u201d\u3002
\u65b0\u589e\u5173\u7cfb\uff1a
\u4e00\u4e2a\u8bfb\u8005\u53ef\u4ee5\u9884\u7ea6\u591a\u672c\u56fe\u4e66\uff1b
\u4e00\u672c\u56fe\u4e66\u53ef\u4ee5\u88ab\u591a\u4e2a\u8bfb\u8005\u9884\u7ea6\uff1b
\u8bfb\u8005\u548c\u56fe\u4e66\u4e4b\u95f4\u901a\u8fc7 reservation \u8868\u5f62\u6210 m:n \u8054\u7cfb\u3002<\/pre>\n\n\n\n
\n\n\n\n5. \u4e3a\u4ec0\u4e48\u9075\u5faa\u6700\u5c0f\u6743\u9650\u539f\u5219\uff1f<\/h2>\n\n\n\n\u6700\u5c0f\u6743\u9650\u539f\u5219\u662f\u6307\u53ea\u7ed9\u7528\u6237\u5b8c\u6210\u5de5\u4f5c\u6240\u5fc5\u9700\u7684\u6743\u9650\uff0c\u4e0d\u6388\u4e88\u591a\u4f59\u6743\u9650\u3002
\u5728\u672c\u5b9e\u9a8c\u4e2d\uff0c\u5982\u679c\u67d0\u7528\u6237\u53ea\u8d1f\u8d23\u67e5\u8be2\u56fe\u4e66\u4fe1\u606f\uff0c\u5219\u53ea\u6388\u4e88 SELECT \u6743\u9650\u5373\u53ef\uff0c\u4e0d\u5e94\u8be5\u6388\u4e88 INSERT\u3001UPDATE\u3001DELETE \u7b49\u6743\u9650\u3002
\u4f8b\u5982\uff1a
GRANT SELECT ON library_db.book TO 'lib_user1'@'localhost';
\u8fd9\u6837\u53ef\u4ee5\u9632\u6b62\u7528\u6237\u8bef\u5220\u3001\u8bef\u6539\u6570\u636e\uff0c\u63d0\u9ad8\u6570\u636e\u5e93\u5b89\u5168\u6027\u3002
\u5982\u679c\u540e\u7eed\u4e0d\u518d\u9700\u8981\u67d0\u9879\u6743\u9650\uff0c\u8fd8\u53ef\u4ee5\u4f7f\u7528 REVOKE \u56de\u6536\u6743\u9650\u3002<\/pre>\n\n\n\n
\n\n\n\n6. \u5e76\u53d1\u501f\u9605\u5e93\u5b58\u4ec5\u52691\u672c\u7684\u56fe\u4e66\u4f1a\u4ea7\u751f\u4ec0\u4e48\u95ee\u9898\uff1f\u5982\u4f55\u89e3\u51b3\uff1f<\/h2>\n\n\n\n\u5f53\u591a\u7528\u6237\u540c\u65f6\u501f\u9605\u540c\u4e00\u672c\u5e93\u5b58\u4ec5\u52691\u672c\u7684\u56fe\u4e66\u65f6\uff0c\u53ef\u80fd\u51fa\u73b0\u8d85\u5356\u95ee\u9898\u3002
\u4f8b\u5982\u4e24\u4e2a\u7528\u6237\u540c\u65f6\u8bfb\u53d6\u5e93\u5b58 stock=1\uff0c\u90fd\u8ba4\u4e3a\u53ef\u4ee5\u501f\u9605\uff0c\u7136\u540e\u540c\u65f6\u63d2\u5165\u501f\u9605\u8bb0\u5f55\u5e76\u6267\u884c\u5e93\u5b58\u51cf1\uff0c\u6700\u7ec8\u53ef\u80fd\u5bfc\u81f4\u5e93\u5b58\u5f02\u5e38\u6216\u51fa\u73b0\u8d85\u989d\u501f\u9605\u3002
\u89e3\u51b3\u65b9\u6cd5\uff1a
1. \u4f7f\u7528\u4e8b\u52a1\u4fdd\u8bc1\u501f\u4e66\u64cd\u4f5c\u7684\u539f\u5b50\u6027\uff1b
2. \u4f7f\u7528 SELECT ... FOR UPDATE \u5bf9\u56fe\u4e66\u5e93\u5b58\u8bb0\u5f55\u52a0\u884c\u7ea7\u9501\uff1b
3. \u5728\u89e6\u53d1\u5668\u4e2d\u5224\u65ad\u5e93\u5b58\u662f\u5426\u5927\u4e8e0\uff1b
4. \u7ed9 stock \u5b57\u6bb5\u8bbe\u7f6e CHECK(stock >= 0) \u7ea6\u675f\u3002
\u793a\u4f8b\uff1a
START TRANSACTION;
SELECT stock
FROM book
WHERE bno='B001'
FOR UPDATE;
UPDATE book
SET stock = stock - 1
WHERE bno='B001'
AND stock > 0;
INSERT INTO borrow(rno,bno,borrowdate,returndate)
VALUES('R2024001','B001','2025-05-01','2025-05-15');
COMMIT;
\u8fd9\u6837\u53ef\u4ee5\u907f\u514d\u591a\u4e2a\u7528\u6237\u540c\u65f6\u4fee\u6539\u5e93\u5b58\u5bfc\u81f4\u6570\u636e\u4e0d\u4e00\u81f4\u3002<\/pre>\n\n\n\n
\n\n\n\n\u5b9e\u9a8c\u603b\u7ed3<\/h1>\n\n\n\n \u901a\u8fc7\u672c\u6b21\u56fe\u4e66\u501f\u9605\u7ba1\u7406\u7cfb\u7edf\u7efc\u5408\u5b9e\u9a8c\uff0c\u6211\u7cfb\u7edf\u5730\u5b8c\u6210\u4e86\u6570\u636e\u5e93\u8bbe\u8ba1\u4e0e\u5b9e\u73b0\u7684\u5168\u8fc7\u7a0b\u3002\u5b9e\u9a8c\u4ece\u9700\u6c42\u5206\u6790\u5f00\u59cb\uff0c\u9010\u6b65\u5b8c\u6210 E-R \u56fe\u8bbe\u8ba1\u3001\u5173\u7cfb\u6a21\u5f0f\u8f6c\u6362\u3001\u7269\u7406\u8868\u7ed3\u6784\u8bbe\u8ba1\u3001\u6570\u636e\u63d2\u5165\u3001\u67e5\u8be2\u64cd\u4f5c\u3001\u89c6\u56fe\u3001\u7d22\u5f15\u3001\u5b8c\u6574\u6027\u7ea6\u675f\u3001\u89e6\u53d1\u5668\u548c\u6743\u9650\u7ba1\u7406\u7b49\u5185\u5bb9\uff0c\u4f7f\u6211\u5bf9\u6570\u636e\u5e93\u5e94\u7528\u7cfb\u7edf\u7684\u8bbe\u8ba1\u6d41\u7a0b\u6709\u4e86\u66f4\u52a0\u5b8c\u6574\u7684\u8ba4\u8bc6\u3002
\u200b
\u5728\u5b9e\u9a8c\u8fc7\u7a0b\u4e2d\uff0c\u6211\u9996\u5148\u6839\u636e\u56fe\u4e66\u9986\u4e1a\u52a1\u9700\u6c42\u5206\u6790\u51fa\u56fe\u4e66\u3001\u8bfb\u8005\u3001\u501f\u9605\u3001\u51fa\u7248\u793e\u3001\u5206\u7c7b\u7b49\u5b9e\u4f53\uff0c\u5e76\u660e\u786e\u4e86\u5b83\u4eec\u4e4b\u95f4\u7684\u8054\u7cfb\u7c7b\u578b\u3002\u4f8b\u5982\uff0c\u51fa\u7248\u793e\u4e0e\u56fe\u4e66\u4e4b\u95f4\u662f\u4e00\u5bf9\u591a\u5173\u7cfb\uff0c\u5206\u7c7b\u4e0e\u56fe\u4e66\u4e4b\u95f4\u662f\u4e00\u5bf9\u591a\u5173\u7cfb\uff0c\u8bfb\u8005\u4e0e\u56fe\u4e66\u4e4b\u95f4\u901a\u8fc7\u501f\u9605\u8868\u5f62\u6210\u591a\u5bf9\u591a\u5173\u7cfb\u3002\u901a\u8fc7 E-R \u56fe\u8bbe\u8ba1\uff0c\u6211\u8fdb\u4e00\u6b65\u7406\u89e3\u4e86\u6982\u5ff5\u7ed3\u6784\u8bbe\u8ba1\u5728\u6570\u636e\u5e93\u5f00\u53d1\u4e2d\u7684\u91cd\u8981\u4f5c\u7528\u3002
\u200b
\u5728\u903b\u8f91\u7ed3\u6784\u8bbe\u8ba1\u9636\u6bb5\uff0c\u6211\u5c06 E-R \u56fe\u8f6c\u6362\u4e3a\u5173\u7cfb\u6a21\u5f0f\uff0c\u5e76\u5206\u6790\u5404\u8868\u662f\u5426\u6ee1\u8db3\u7b2c\u4e09\u8303\u5f0f\u3002\u901a\u8fc7\u89c4\u8303\u5316\u8bbe\u8ba1\uff0c\u907f\u514d\u4e86\u5728\u501f\u9605\u8868\u4e2d\u91cd\u590d\u4fdd\u5b58\u8bfb\u8005\u59d3\u540d\u3001\u56fe\u4e66\u540d\u79f0\u7b49\u4fe1\u606f\uff0c\u51cf\u5c11\u4e86\u6570\u636e\u5197\u4f59\uff0c\u63d0\u9ad8\u4e86\u6570\u636e\u4e00\u81f4\u6027\u3002\u5728\u7269\u7406\u8bbe\u8ba1\u9636\u6bb5\uff0c\u6211\u4f7f\u7528 SQL \u521b\u5efa\u6570\u636e\u5e93\u548c\u6570\u636e\u8868\uff0c\u8bbe\u7f6e\u4e86\u4e3b\u952e\u3001\u5916\u952e\u3001\u975e\u7a7a\u3001\u9ed8\u8ba4\u503c\u548c CHECK \u7ea6\u675f\uff0c\u5bf9\u5b9e\u4f53\u5b8c\u6574\u6027\u3001\u53c2\u7167\u5b8c\u6574\u6027\u548c\u7528\u6237\u5b9a\u4e49\u5b8c\u6574\u6027\u6709\u4e86\u66f4\u6df1\u523b\u7684\u7406\u89e3\u3002
\u200b
\u5728\u6570\u636e\u64cd\u4f5c\u90e8\u5206\uff0c\u6211\u7ec3\u4e60\u4e86 INSERT\u3001UPDATE\u3001DELETE \u548c SELECT \u8bed\u53e5\uff0c\u5e76\u5b8c\u6210\u4e86\u57fa\u7840\u67e5\u8be2\u3001\u805a\u5408\u67e5\u8be2\u3001\u591a\u8868\u8fde\u63a5\u67e5\u8be2\u3001\u5d4c\u5957\u67e5\u8be2\u548c\u96c6\u5408\u67e5\u8be2\u7b49\u5185\u5bb9\u3002\u901a\u8fc7\u8fd9\u4e9b\u7ec3\u4e60\uff0c\u6211\u638c\u63e1\u4e86 SQL \u67e5\u8be2\u8bed\u53e5\u7684\u5e38\u89c1\u5199\u6cd5\uff0c\u5c24\u5176\u662f\u591a\u8868\u8fde\u63a5\u548c\u5d4c\u5957\u67e5\u8be2\u7684\u4f7f\u7528\u65b9\u6cd5\u3002\u5b9e\u9a8c\u4e2d\u8fd8\u521b\u5efa\u4e86\u89c6\u56fe\u548c\u7d22\u5f15\uff0c\u7406\u89e3\u4e86\u89c6\u56fe\u53ef\u4ee5\u7b80\u5316\u590d\u6742\u67e5\u8be2\uff0c\u7d22\u5f15\u53ef\u4ee5\u63d0\u9ad8\u67e5\u8be2\u6548\u7387\uff0c\u4f46\u4e5f\u4f1a\u589e\u52a0\u7ef4\u62a4\u6210\u672c\u3002
\u200b
\u5728\u89e6\u53d1\u5668\u90e8\u5206\uff0c\u6211\u5b9e\u73b0\u4e86\u501f\u4e66\u81ea\u52a8\u51cf\u5c11\u5e93\u5b58\u3001\u8fd8\u4e66\u81ea\u52a8\u589e\u52a0\u5e93\u5b58\u5e76\u8ba1\u7b97\u7f5a\u6b3e\u3001\u5220\u9664\u8bfb\u8005\u524d\u8bb0\u5f55\u65e5\u5fd7\u7b49\u529f\u80fd\u3002\u901a\u8fc7\u89e6\u53d1\u5668\u5b9e\u9a8c\uff0c\u6211\u8ba4\u8bc6\u5230\u6570\u636e\u5e93\u4e0d\u4ec5\u53ef\u4ee5\u5b58\u50a8\u6570\u636e\uff0c\u8fd8\u53ef\u4ee5\u5728\u7279\u5b9a\u64cd\u4f5c\u53d1\u751f\u65f6\u81ea\u52a8\u6267\u884c\u4e00\u4e9b\u4e1a\u52a1\u903b\u8f91\u3002\u5b9e\u9a8c\u8fc7\u7a0b\u4e2d\u4e5f\u9047\u5230\u4e86\u4e00\u4e9b\u95ee\u9898\uff0c\u4f8b\u5982\u5916\u952e\u7ea6\u675f\u5bfc\u81f4\u6570\u636e\u65e0\u6cd5\u5220\u9664\u3001CHECK \u7ea6\u675f\u63d2\u5165\u5931\u8d25\u3001\u89e6\u53d1\u5668\u8bed\u6cd5\u9519\u8bef\u7b49\u3002\u901a\u8fc7\u67e5\u770b\u9519\u8bef\u4fe1\u606f\u3001\u4fee\u6539 SQL \u8bed\u53e5\u548c\u53cd\u590d\u6d4b\u8bd5\uff0c\u6700\u7ec8\u89e3\u51b3\u4e86\u8fd9\u4e9b\u95ee\u9898\u3002
\u200b
\u901a\u8fc7\u672c\u6b21\u5b9e\u9a8c\uff0c\u6211\u4e0d\u4ec5\u5de9\u56fa\u4e86\u6570\u636e\u5e93\u7406\u8bba\u77e5\u8bc6\uff0c\u4e5f\u63d0\u9ad8\u4e86 SQL \u7f16\u5199\u80fd\u529b\u548c\u6570\u636e\u5e93\u8c03\u8bd5\u80fd\u529b\u3002\u4eca\u540e\u5728\u8bbe\u8ba1\u6570\u636e\u5e93\u7cfb\u7edf<\/pre>\n","protected":false},"excerpt":{"rendered":"\u6570\u636e\u5e93\u7efc\u5408\u5b9e\u9a8c 1.\u9700\u6c42\u5206\u6790 \u67d0\u5927\u578b\u56fe\u4e66\u9986\u9700\u8981\u5f00\u53d1\u4e00\u5957\u6570\u5b57\u5316\u501f\u9605\u7ba1\u7406\u7cfb\u7edf\uff0c\u4e3b\u8981\u4e1a\u52a1\u9700\u6c42\u5982\u4e0b\uff1a \u56fe\u4e66\u4fe1\u606f\uff1a\u8bb0\u5f55\u56fe […]<\/p>\n","protected":false},"author":1,"featured_media":448,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[9],"tags":[],"class_list":["post-446","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-wenzhang"],"_links":{"self":[{"href":"https:\/\/fg2025.cn\/index.php\/wp-json\/wp\/v2\/posts\/446","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/fg2025.cn\/index.php\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/fg2025.cn\/index.php\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/fg2025.cn\/index.php\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/fg2025.cn\/index.php\/wp-json\/wp\/v2\/comments?post=446"}],"version-history":[{"count":0,"href":"https:\/\/fg2025.cn\/index.php\/wp-json\/wp\/v2\/posts\/446\/revisions"}],"wp:attachment":[{"href":"https:\/\/fg2025.cn\/index.php\/wp-json\/wp\/v2\/media?parent=446"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/fg2025.cn\/index.php\/wp-json\/wp\/v2\/categories?post=446"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/fg2025.cn\/index.php\/wp-json\/wp\/v2\/tags?post=446"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}
SELECT rname AS name
FROM reader
UNION
SELECT author AS name
FROM book;
2.UNION ALL\uff1a\u5408\u5e76\u8bfb\u8005\u59d3\u540d\u548c\u4f5c\u8005\u59d3\u540d\uff0c\u4e0d\u53bb\u91cd
SELECT rname AS name
FROM reader
UNION ALL
SELECT author AS name
FROM book;
3.\u6a21\u62df INTERSECT\uff1a\u67e5\u8be2\u501f\u8fc7\u4e66\u7684\u8bfb\u8005\u8bc1\u53f7
SELECT rno
FROM reader
WHERE rno IN(
SELECT rno
FROM borrow
);
4.\u6a21\u62df EXCEPT\uff1a\u67e5\u8be2\u6ca1\u6709\u501f\u4e66\u7684\u8bfb\u8005
SELECT rno,rname
FROM reader
WHERE rno NOT IN(
SELECT rno
FROM borrow
);<\/pre>\n\n\n\n
11.\u89c6\u56fe\u64cd\u4f5c<\/h2>\n\n\n\n1.\u521b\u5efa\u672a\u5f52\u8fd8\u56fe\u4e66\u89c6\u56fe
CREATE VIEW v_unreturned AS
SELECT br.borrowid, r.rname, b.bname,
br.borrowdate, br.returndate
FROM borrow br
JOIN reader r ON br.rno = r.rno
JOIN book b ON br.bno = b.bno
WHERE br.actualdate IS NULL;
2.\u67e5\u8be2\u89c6\u56fe
SELECT * FROM v_unreturned;
3.\u521b\u5efa\u5b66\u751f\u8bfb\u8005\u89c6\u56fe\uff0c\u5e26 WITH CHECK OPTION
CREATE VIEW v_student_reader AS
SELECT *
FROM reader
WHERE dept LIKE '%\u5b66\u9662%'
WITH CHECK OPTION;
4.\u6d4b\u8bd5\u53ef\u66f4\u65b0\u89c6\u56fe
UPDATE v_student_reader
SET phone = '18800000000'
WHERE rno = 'R2024002';
\u8bf4\u660e\uff1a
\u8be5\u89c6\u56fe\u57fa\u4e8e\u5355\u8868 reader \u521b\u5efa\uff0c\u6ca1\u6709\u805a\u5408\u51fd\u6570\u3001\u5206\u7ec4\u548c\u8fde\u63a5\uff0c\u56e0\u6b64\u5c5e\u4e8e\u53ef\u66f4\u65b0\u89c6\u56fe\u3002
5.\u521b\u5efa\u4e0d\u53ef\u66f4\u65b0\u7684\u805a\u5408\u89c6\u56fe
CREATE VIEW v_press_count AS
SELECT press, COUNT(*) AS total
FROM book
GROUP BY press;
\u8bf4\u660e\uff1a
\u8be5\u89c6\u56fe\u4f7f\u7528\u4e86 GROUP BY \u548c COUNT \u805a\u5408\u51fd\u6570\uff0c\u56e0\u6b64\u4e00\u822c\u4e0d\u80fd\u76f4\u63a5\u66f4\u65b0\u3002
6.\u5220\u9664\u89c6\u56fe
DROP VIEW v_unreturned;
DROP VIEW v_student_reader;
DROP VIEW v_press_count;<\/pre>\n\n\n\n12.\u7d22\u5f15<\/h2>\n\n\n\n1.\u521b\u5efa\u666e\u901a\u7d22\u5f15
CREATE INDEX idx_book_bname
ON book(bname);
2.\u521b\u5efa\u552f\u4e00\u7d22\u5f15
CREATE UNIQUE INDEX idx_reader_phone
ON reader(phone);
3.\u521b\u5efa\u590d\u5408\u7d22\u5f15
CREATE INDEX idx_borrow_rno_bno
ON borrow(rno,bno);
\u67e5\u770b\u7d22\u5f15
SHOW INDEX FROM book;
SHOW INDEX FROM reader;
SHOW INDEX FROM borrow;
\u5220\u9664\u7d22\u5f15
DROP INDEX idx_book_bname ON book;
DROP INDEX idx_reader_phone ON reader;
DROP INDEX idx_borrow_rno_bno ON borrow;<\/pre>\n\n\n\n13.\u6570\u636e\u5b8c\u6574\u6027\u7ea6\u675f\u9a8c\u8bc1\u4e0e\u7ea7\u8054\u64cd\u4f5c<\/h2>\n\n\n\n1.\u5b9e\u4f53\u5b8c\u6574\u6027\u9a8c\u8bc1\uff1a\u4e3b\u952e\u4e0d\u80fd\u4e3a\u7a7a
INSERT INTO book(bno,bname,author,press,pubyear,stock)
VALUES(NULL,'\u6d4b\u8bd5\u4e66','\u6d4b\u8bd5\u4f5c\u8005','\u6d4b\u8bd5\u51fa\u7248\u793e',2020,1);
\u8bf4\u660e\uff1a
bno \u662f book \u8868\u4e3b\u952e\uff0c\u4e3b\u952e\u4e0d\u80fd\u4e3a\u7a7a\uff0c\u56e0\u6b64\u63d2\u5165\u5931\u8d25\u3002
2.\u53c2\u7167\u5b8c\u6574\u6027\u9a8c\u8bc1\uff1a\u63d2\u5165\u4e0d\u5b58\u5728\u7684\u56fe\u4e66\u7f16\u53f7
INSERT INTO borrow(rno,bno,borrowdate,returndate,actualdate)
VALUES('R2024001','B999','2025-05-01','2025-05-15',NULL);
\u8bf4\u660e\uff1a
B999 \u5728 book \u8868\u4e2d\u4e0d\u5b58\u5728\uff0cborrow.bno \u662f\u5916\u952e\uff0c\u56e0\u6b64\u8fdd\u53cd\u53c2\u7167\u5b8c\u6574\u6027\u3002
3.\u7528\u6237\u5b9a\u4e49\u5b8c\u6574\u6027\u9a8c\u8bc1\uff1a\u5e93\u5b58\u4e0d\u80fd\u5c0f\u4e8e0
UPDATE book
SET stock = -1
WHERE bno = 'B001';
\u8bf4\u660e\uff1a
stock \u5b57\u6bb5\u8bbe\u7f6e\u4e86 CHECK(stock>=0)\uff0c\u5e93\u5b58\u4e0d\u80fd\u4e3a\u8d1f\u6570\u3002
4.\u7528\u6237\u5b9a\u4e49\u5b8c\u6574\u6027\u9a8c\u8bc1\uff1a\u5e93\u5b58\u4e0d\u80fd\u5c0f\u4e8e0
UPDATE book
SET stock = -1
WHERE bno = 'B001';
\u8bf4\u660e\uff1a
stock \u5b57\u6bb5\u8bbe\u7f6e\u4e86 CHECK(stock>=0)\uff0c\u5e93\u5b58\u4e0d\u80fd\u4e3a\u8d1f\u6570\u3002
5.ON UPDATE CASCADE \u6d4b\u8bd5
UPDATE reader
SET rno = 'R2024999'
WHERE rno = 'R2024003';
SELECT * FROM borrow
WHERE rno = 'R2024999';
\u8bf4\u660e\uff1a
reader.rno \u66f4\u65b0\u540e\uff0cborrow \u8868\u4e2d\u5bf9\u5e94\u7684\u5916\u952e rno \u4f1a\u81ea\u52a8\u540c\u6b65\u66f4\u65b0\u3002<\/pre>\n\n\n\n14.\u89e6\u53d1\u5668<\/h2>\n\n\n\n\u51c6\u5907\uff1a\u5220\u9664\u65e7\u89e6\u53d1\u5668
DROP TRIGGER IF EXISTS trg_borrow_before_insert;
DROP TRIGGER IF EXISTS trg_return_after_update;
DROP TRIGGER IF EXISTS trg_reader_before_delete;
\u521b\u5efa\u5220\u9664\u8bfb\u8005\u65e5\u5fd7\u8868
CREATE TABLE reader_delete_log(
logid INT AUTO_INCREMENT PRIMARY KEY,
rno CHAR(12),
rname VARCHAR(20),
dept VARCHAR(40),
delete_time DATETIME DEFAULT CURRENT_TIMESTAMP
);
1.\u501f\u4e66\u65f6\u81ea\u52a8\u51cf\u5c11\u5e93\u5b58
DELIMITER \/\/
CREATE TRIGGER trg_borrow_before_insert
BEFORE INSERT ON borrow
FOR EACH ROW
BEGIN
DECLARE v_stock INT;
SELECT stock INTO v_stock
FROM book
WHERE bno = NEW.bno;
IF v_stock <= 0 THEN
SIGNAL SQLSTATE '45000'
SET MESSAGE_TEXT = '\u5e93\u5b58\u4e0d\u8db3\uff0c\u4e0d\u80fd\u501f\u4e66';
ELSE
UPDATE book
SET stock = stock - 1
WHERE bno = NEW.bno;
END IF;
END \/\/
DELIMITER ;
\u6d4b\u8bd5\uff1a
SELECT stock FROM book WHERE bno='B003';
INSERT INTO borrow(rno,bno,borrowdate,returndate,actualdate)
VALUES('R2024002','B003','2025-05-01','2025-05-15',NULL);
SELECT stock FROM book WHERE bno='B003';
2.\u8fd8\u4e66\u65f6\u81ea\u52a8\u589e\u52a0\u5e93\u5b58\u5e76\u8ba1\u7b97\u7f5a\u6b3e
DELIMITER \/\/
CREATE TRIGGER trg_return_after_update
AFTER UPDATE ON borrow
FOR EACH ROW
BEGIN
IF OLD.actualdate IS NULL AND NEW.actualdate IS NOT NULL THEN
UPDATE book
SET stock = stock + 1
WHERE bno = NEW.bno;
UPDATE borrow
SET fine =
CASE
WHEN NEW.actualdate > NEW.returndate
THEN DATEDIFF(NEW.actualdate, NEW.returndate) * 1
ELSE 0
END
WHERE borrowid = NEW.borrowid;
END IF;
END \/\/
DELIMITER ;
\u6d4b\u8bd5\uff1a
UPDATE borrow
SET actualdate = '2025-05-18'
WHERE rno='R2024002'
AND bno='B003'
AND borrowdate='2025-05-01';
SELECT * FROM borrow
WHERE rno='R2024002'
AND bno='B003';
SELECT stock FROM book WHERE bno='B003';
3.\u5220\u9664\u8bfb\u8005\u524d\u8bb0\u5f55\u65e5\u5fd7
DELIMITER \/\/
CREATE TRIGGER trg_reader_before_delete
BEFORE DELETE ON reader
FOR EACH ROW
BEGIN
INSERT INTO reader_delete_log(rno,rname,dept)
VALUES(OLD.rno, OLD.rname, OLD.dept);
END \/\/
DELIMITER ;
\u6d4b\u8bd5\uff1a
INSERT INTO reader
VALUES('R2024888','\u65e5\u5fd7\u6d4b\u8bd5','\u7537','\u6d4b\u8bd5\u5b66\u9662','\u65e0');
DELETE FROM reader
WHERE rno='R2024888';
SELECT * FROM reader_delete_log;<\/pre>\n\n\n\n15.\u6570\u636e\u5b89\u5168\u6027<\/h2>\n\n\n\n1.\u521b\u5efa\u7528\u6237\u5e76\u6388\u4e88\u67e5\u8be2\u6743\u9650
CREATE USER 'lib_user1'@'localhost'
IDENTIFIED BY '123456';
GRANT SELECT
ON library_db.book
TO 'lib_user1'@'localhost';
\u67e5\u770b\u6743\u9650\uff1a
SHOW GRANTS FOR 'lib_user1'@'localhost';
2.\u6388\u4e88\u6743\u9650\u5e76\u5141\u8bb8\u8f6c\u6388\u6743
GRANT SELECT, INSERT
ON library_db.reader
TO 'lib_user1'@'localhost'
WITH GRANT OPTION;
\u8bf4\u660e\uff1a
WITH GRANT OPTION \u8868\u793a\u8be5\u7528\u6237\u53ef\u4ee5\u5c06\u81ea\u5df1\u62e5\u6709\u7684\u6743\u9650\u518d\u6388\u4e88\u5176\u4ed6\u7528\u6237\u3002
3.\u56de\u6536\u6743\u9650
REVOKE INSERT
ON library_db.reader
FROM 'lib_user1'@'localhost';
4.\u521b\u5efa\u89d2\u8272\u5e76\u6388\u6743
CREATE ROLE 'reader_role';
GRANT SELECT
ON library_db.*
TO 'reader_role';
CREATE USER 'lib_user2'@'localhost'
IDENTIFIED BY '123456';
GRANT 'reader_role'
TO 'lib_user2'@'localhost';
SET DEFAULT ROLE 'reader_role'
TO 'lib_user2'@'localhost';<\/pre>\n\n\n\n16.\u89c6\u56fe\u4e0e\u6d3e\u751f\u8868<\/h2>\n\n\n\n1.\u5e26\u805a\u5408\u51fd\u6570\u7684\u89c6\u56fe\uff1a\u7edf\u8ba1\u6bcf\u4e2a\u8bfb\u8005\u501f\u9605\u6b21\u6570
CREATE VIEW v_reader_borrow_count AS
SELECT r.rno, r.rname, COUNT(br.borrowid) AS borrow_count
FROM reader r
LEFT JOIN borrow br
ON r.rno = br.rno
GROUP BY r.rno, r.rname;
\u67e5\u8be2\uff1a
SELECT * FROM v_reader_borrow_count;
2.\u6d3e\u751f\u8868\uff1a\u67e5\u8be2\u501f\u9605\u6b21\u6570\u5927\u4e8e1\u7684\u8bfb\u8005
SELECT *
FROM (
SELECT rno, COUNT(*) AS borrow_count
FROM borrow
GROUP BY rno
) AS t
WHERE t.borrow_count > 1;
3.WITH \u5b50\u53e5\u7edf\u8ba1\u6bcf\u4f4d\u8bfb\u8005\u501f\u9605\u6570\u91cf
WITH reader_count AS (
SELECT rno, COUNT(*) AS total
FROM borrow
GROUP BY rno
)
SELECT r.rno, r.rname, rc.total
FROM reader r
LEFT JOIN reader_count rc
ON r.rno = rc.rno;
4.WITH \u5b50\u53e5\uff1a\u67e5\u8be2\u672a\u5f52\u8fd8\u56fe\u4e66
WITH unreturned AS (
SELECT br.borrowid, r.rname, b.bname,
br.borrowdate, br.returndate
FROM borrow br
JOIN reader r ON br.rno = r.rno
JOIN book b ON br.bno = b.bno
WHERE br.actualdate IS NULL
)
SELECT * FROM unreturned;<\/pre>\n\n\n\n17.\u6269\u5c55\u601d\u8003<\/h2>\n\n\n\n\n- \u5982\u4f55\u5904\u7406\u5206\u7c7b\u5b9e\u4f53\u7684\u81ea\u5173\u8054\uff1f<\/li>\n<\/ol>\n\n\n\n
\u5206\u7c7b\u5b9e\u4f53\u5b58\u5728\u201c\u4e0a\u7ea7\u5206\u7c7b\u201d\u548c\u201c\u4e0b\u7ea7\u5206\u7c7b\u201d\u7684\u5173\u7cfb\uff0c\u56e0\u6b64\u53ef\u4ee5\u5728 category \u8868\u4e2d\u8bbe\u7f6e parentid \u5b57\u6bb5\u3002
category(
cid,
cname,
parentid
)
\u5176\u4e2d cid \u662f\u5206\u7c7b\u7f16\u53f7\uff0cparentid \u662f\u4e0a\u7ea7\u5206\u7c7b\u7f16\u53f7\uff0c\u540c\u65f6 parentid \u4e5f\u662f\u6307\u5411 category.cid \u7684\u5916\u952e\u3002
\u5982\u679c\u67d0\u5206\u7c7b\u6ca1\u6709\u4e0a\u7ea7\u5206\u7c7b\uff0c\u5219 parentid \u53ef\u4ee5\u4e3a\u7a7a\u3002
\u8fd9\u79cd\u8bbe\u8ba1\u53ef\u4ee5\u8868\u793a\u6811\u5f62\u7ed3\u6784\uff0c\u4f8b\u5982\uff1a
\u56fe\u4e66
\u251c\u2500\u2500 \u8ba1\u7b97\u673a
\u2502 \u251c\u2500\u2500 \u6570\u636e\u5e93
\u2502 \u2514\u2500\u2500 \u7f51\u7edc\u6280\u672f
\u2514\u2500\u2500 \u6587\u5b66
\u2514\u2500\u2500 \u79d1\u5e7b\u5c0f\u8bf4<\/pre>\n\n\n\n
\n\n\n\n2. \u501f\u9605\u5173\u7cfb\u662f\u5426\u53ef\u80fd\u5b58\u5728\u6570\u636e\u5197\u4f59\uff1f<\/h2>\n\n\n\n\u501f\u9605\u8868\u5982\u679c\u53ea\u4fdd\u5b58 rno\u3001bno\u3001borrowdate\u3001returndate\u3001actualdate \u7b49\u4fe1\u606f\uff0c\u5219\u5197\u4f59\u8f83\u5c11\u3002
\u4f46\u662f\u5982\u679c\u5728 borrow \u8868\u4e2d\u540c\u65f6\u4fdd\u5b58\u8bfb\u8005\u59d3\u540d rname\u3001\u56fe\u4e66\u540d\u79f0 bname\u3001\u51fa\u7248\u793e press \u7b49\u4fe1\u606f\uff0c\u5c31\u4f1a\u4ea7\u751f\u6570\u636e\u5197\u4f59\u3002
\u4f8b\u5982\uff1a
borrow(borrowid, rno, rname, bno, bname, borrowdate)
\u5176\u4e2d rname \u4f9d\u8d56 rno\uff0cbname \u4f9d\u8d56 bno\uff0c\u800c\u4e0d\u662f\u76f4\u63a5\u4f9d\u8d56 borrowid\uff0c\u4f1a\u4ea7\u751f\u4f20\u9012\u4f9d\u8d56\u3002
\u89c4\u8303\u5316\u65b9\u6848\uff1a
\u5c06\u8bfb\u8005\u4fe1\u606f\u4fdd\u5b58\u5728 reader \u8868\uff1b
\u5c06\u56fe\u4e66\u4fe1\u606f\u4fdd\u5b58\u5728 book \u8868\uff1b
borrow \u8868\u53ea\u4fdd\u5b58\u8bfb\u8005\u8bc1\u53f7\u548c\u56fe\u4e66\u7f16\u53f7\u4f5c\u4e3a\u5916\u952e\u3002<\/pre>\n\n\n\n
\n\n\n\n3. \u5982\u4f55\u9632\u6b62\u5e93\u5b58\u4e3a\u8d1f\u6570\uff1f<\/h2>\n\n\n\n\u53ef\u4ee5\u4ece\u4e24\u4e2a\u65b9\u9762\u9632\u6b62\u5e93\u5b58\u4e3a\u8d1f\u6570\uff1a
\u7b2c\u4e00\uff0c\u5728 book \u8868\u4e2d\u8bbe\u7f6e CHECK(stock >= 0) \u7ea6\u675f\uff0c\u4fdd\u8bc1\u5e93\u5b58\u4e0d\u80fd\u5c0f\u4e8e0\u3002
\u7b2c\u4e8c\uff0c\u5728\u501f\u4e66\u89e6\u53d1\u5668\u4e2d\u5224\u65ad\u5e93\u5b58\u6570\u91cf\u3002
\u5f53\u63d2\u5165 borrow \u501f\u9605\u8bb0\u5f55\u65f6\uff0c\u5148\u67e5\u8be2\u56fe\u4e66\u5e93\u5b58\u3002
\u5982\u679c\u5e93\u5b58\u5c0f\u4e8e\u7b49\u4e8e0\uff0c\u5219\u4f7f\u7528 SIGNAL \u629b\u51fa\u9519\u8bef\uff0c\u963b\u6b62\u501f\u4e66\u64cd\u4f5c\uff1b
\u5982\u679c\u5e93\u5b58\u5927\u4e8e0\uff0c\u5219\u5141\u8bb8\u501f\u9605\uff0c\u5e76\u81ea\u52a8\u5c06\u5e93\u5b58\u51cf1\u3002
\u8fd9\u6837\u53ef\u4ee5\u4fdd\u8bc1\u501f\u4e66\u65f6\u4e0d\u4f1a\u51fa\u73b0\u5e93\u5b58\u4e3a\u8d1f\u6570\u7684\u60c5\u51b5\u3002<\/pre>\n\n\n\n
\n\n\n\n4. \u9884\u7ea6\u56fe\u4e66\u529f\u80fd\u9700\u8981\u589e\u52a0\u54ea\u4e9b\u5b9e\u4f53\u548c\u5173\u7cfb\uff1f<\/h2>\n\n\n\n\u5982\u679c\u7cfb\u7edf\u652f\u6301\u9884\u7ea6\u56fe\u4e66\u529f\u80fd\uff0c\u53ef\u4ee5\u589e\u52a0 reservation \u9884\u7ea6\u8868\u3002
reservation(
reserveid,
rno,
bno,
reservedate,
status
)
\u5176\u4e2d\uff1a
reserveid \u8868\u793a\u9884\u7ea6\u7f16\u53f7\uff1b
rno \u662f\u8bfb\u8005\u8bc1\u53f7\uff0c\u5916\u952e\u5f15\u7528 reader.rno\uff1b
bno \u662f\u56fe\u4e66\u7f16\u53f7\uff0c\u5916\u952e\u5f15\u7528 book.bno\uff1b
reservedate \u8868\u793a\u9884\u7ea6\u65e5\u671f\uff1b
status \u8868\u793a\u9884\u7ea6\u72b6\u6001\uff0c\u5982\u201c\u9884\u7ea6\u4e2d\u201d\u201c\u5df2\u53d6\u6d88\u201d\u201c\u5df2\u5b8c\u6210\u201d\u3002
\u65b0\u589e\u5173\u7cfb\uff1a
\u4e00\u4e2a\u8bfb\u8005\u53ef\u4ee5\u9884\u7ea6\u591a\u672c\u56fe\u4e66\uff1b
\u4e00\u672c\u56fe\u4e66\u53ef\u4ee5\u88ab\u591a\u4e2a\u8bfb\u8005\u9884\u7ea6\uff1b
\u8bfb\u8005\u548c\u56fe\u4e66\u4e4b\u95f4\u901a\u8fc7 reservation \u8868\u5f62\u6210 m:n \u8054\u7cfb\u3002<\/pre>\n\n\n\n
\n\n\n\n5. \u4e3a\u4ec0\u4e48\u9075\u5faa\u6700\u5c0f\u6743\u9650\u539f\u5219\uff1f<\/h2>\n\n\n\n\u6700\u5c0f\u6743\u9650\u539f\u5219\u662f\u6307\u53ea\u7ed9\u7528\u6237\u5b8c\u6210\u5de5\u4f5c\u6240\u5fc5\u9700\u7684\u6743\u9650\uff0c\u4e0d\u6388\u4e88\u591a\u4f59\u6743\u9650\u3002
\u5728\u672c\u5b9e\u9a8c\u4e2d\uff0c\u5982\u679c\u67d0\u7528\u6237\u53ea\u8d1f\u8d23\u67e5\u8be2\u56fe\u4e66\u4fe1\u606f\uff0c\u5219\u53ea\u6388\u4e88 SELECT \u6743\u9650\u5373\u53ef\uff0c\u4e0d\u5e94\u8be5\u6388\u4e88 INSERT\u3001UPDATE\u3001DELETE \u7b49\u6743\u9650\u3002
\u4f8b\u5982\uff1a
GRANT SELECT ON library_db.book TO 'lib_user1'@'localhost';
\u8fd9\u6837\u53ef\u4ee5\u9632\u6b62\u7528\u6237\u8bef\u5220\u3001\u8bef\u6539\u6570\u636e\uff0c\u63d0\u9ad8\u6570\u636e\u5e93\u5b89\u5168\u6027\u3002
\u5982\u679c\u540e\u7eed\u4e0d\u518d\u9700\u8981\u67d0\u9879\u6743\u9650\uff0c\u8fd8\u53ef\u4ee5\u4f7f\u7528 REVOKE \u56de\u6536\u6743\u9650\u3002<\/pre>\n\n\n\n
\n\n\n\n6. \u5e76\u53d1\u501f\u9605\u5e93\u5b58\u4ec5\u52691\u672c\u7684\u56fe\u4e66\u4f1a\u4ea7\u751f\u4ec0\u4e48\u95ee\u9898\uff1f\u5982\u4f55\u89e3\u51b3\uff1f<\/h2>\n\n\n\n\u5f53\u591a\u7528\u6237\u540c\u65f6\u501f\u9605\u540c\u4e00\u672c\u5e93\u5b58\u4ec5\u52691\u672c\u7684\u56fe\u4e66\u65f6\uff0c\u53ef\u80fd\u51fa\u73b0\u8d85\u5356\u95ee\u9898\u3002
\u4f8b\u5982\u4e24\u4e2a\u7528\u6237\u540c\u65f6\u8bfb\u53d6\u5e93\u5b58 stock=1\uff0c\u90fd\u8ba4\u4e3a\u53ef\u4ee5\u501f\u9605\uff0c\u7136\u540e\u540c\u65f6\u63d2\u5165\u501f\u9605\u8bb0\u5f55\u5e76\u6267\u884c\u5e93\u5b58\u51cf1\uff0c\u6700\u7ec8\u53ef\u80fd\u5bfc\u81f4\u5e93\u5b58\u5f02\u5e38\u6216\u51fa\u73b0\u8d85\u989d\u501f\u9605\u3002
\u89e3\u51b3\u65b9\u6cd5\uff1a
1. \u4f7f\u7528\u4e8b\u52a1\u4fdd\u8bc1\u501f\u4e66\u64cd\u4f5c\u7684\u539f\u5b50\u6027\uff1b
2. \u4f7f\u7528 SELECT ... FOR UPDATE \u5bf9\u56fe\u4e66\u5e93\u5b58\u8bb0\u5f55\u52a0\u884c\u7ea7\u9501\uff1b
3. \u5728\u89e6\u53d1\u5668\u4e2d\u5224\u65ad\u5e93\u5b58\u662f\u5426\u5927\u4e8e0\uff1b
4. \u7ed9 stock \u5b57\u6bb5\u8bbe\u7f6e CHECK(stock >= 0) \u7ea6\u675f\u3002
\u793a\u4f8b\uff1a
START TRANSACTION;
SELECT stock
FROM book
WHERE bno='B001'
FOR UPDATE;
UPDATE book
SET stock = stock - 1
WHERE bno='B001'
AND stock > 0;
INSERT INTO borrow(rno,bno,borrowdate,returndate)
VALUES('R2024001','B001','2025-05-01','2025-05-15');
COMMIT;
\u8fd9\u6837\u53ef\u4ee5\u907f\u514d\u591a\u4e2a\u7528\u6237\u540c\u65f6\u4fee\u6539\u5e93\u5b58\u5bfc\u81f4\u6570\u636e\u4e0d\u4e00\u81f4\u3002<\/pre>\n\n\n\n
\n\n\n\n\u5b9e\u9a8c\u603b\u7ed3<\/h1>\n\n\n\n \u901a\u8fc7\u672c\u6b21\u56fe\u4e66\u501f\u9605\u7ba1\u7406\u7cfb\u7edf\u7efc\u5408\u5b9e\u9a8c\uff0c\u6211\u7cfb\u7edf\u5730\u5b8c\u6210\u4e86\u6570\u636e\u5e93\u8bbe\u8ba1\u4e0e\u5b9e\u73b0\u7684\u5168\u8fc7\u7a0b\u3002\u5b9e\u9a8c\u4ece\u9700\u6c42\u5206\u6790\u5f00\u59cb\uff0c\u9010\u6b65\u5b8c\u6210 E-R \u56fe\u8bbe\u8ba1\u3001\u5173\u7cfb\u6a21\u5f0f\u8f6c\u6362\u3001\u7269\u7406\u8868\u7ed3\u6784\u8bbe\u8ba1\u3001\u6570\u636e\u63d2\u5165\u3001\u67e5\u8be2\u64cd\u4f5c\u3001\u89c6\u56fe\u3001\u7d22\u5f15\u3001\u5b8c\u6574\u6027\u7ea6\u675f\u3001\u89e6\u53d1\u5668\u548c\u6743\u9650\u7ba1\u7406\u7b49\u5185\u5bb9\uff0c\u4f7f\u6211\u5bf9\u6570\u636e\u5e93\u5e94\u7528\u7cfb\u7edf\u7684\u8bbe\u8ba1\u6d41\u7a0b\u6709\u4e86\u66f4\u52a0\u5b8c\u6574\u7684\u8ba4\u8bc6\u3002
\u200b
\u5728\u5b9e\u9a8c\u8fc7\u7a0b\u4e2d\uff0c\u6211\u9996\u5148\u6839\u636e\u56fe\u4e66\u9986\u4e1a\u52a1\u9700\u6c42\u5206\u6790\u51fa\u56fe\u4e66\u3001\u8bfb\u8005\u3001\u501f\u9605\u3001\u51fa\u7248\u793e\u3001\u5206\u7c7b\u7b49\u5b9e\u4f53\uff0c\u5e76\u660e\u786e\u4e86\u5b83\u4eec\u4e4b\u95f4\u7684\u8054\u7cfb\u7c7b\u578b\u3002\u4f8b\u5982\uff0c\u51fa\u7248\u793e\u4e0e\u56fe\u4e66\u4e4b\u95f4\u662f\u4e00\u5bf9\u591a\u5173\u7cfb\uff0c\u5206\u7c7b\u4e0e\u56fe\u4e66\u4e4b\u95f4\u662f\u4e00\u5bf9\u591a\u5173\u7cfb\uff0c\u8bfb\u8005\u4e0e\u56fe\u4e66\u4e4b\u95f4\u901a\u8fc7\u501f\u9605\u8868\u5f62\u6210\u591a\u5bf9\u591a\u5173\u7cfb\u3002\u901a\u8fc7 E-R \u56fe\u8bbe\u8ba1\uff0c\u6211\u8fdb\u4e00\u6b65\u7406\u89e3\u4e86\u6982\u5ff5\u7ed3\u6784\u8bbe\u8ba1\u5728\u6570\u636e\u5e93\u5f00\u53d1\u4e2d\u7684\u91cd\u8981\u4f5c\u7528\u3002
\u200b
\u5728\u903b\u8f91\u7ed3\u6784\u8bbe\u8ba1\u9636\u6bb5\uff0c\u6211\u5c06 E-R \u56fe\u8f6c\u6362\u4e3a\u5173\u7cfb\u6a21\u5f0f\uff0c\u5e76\u5206\u6790\u5404\u8868\u662f\u5426\u6ee1\u8db3\u7b2c\u4e09\u8303\u5f0f\u3002\u901a\u8fc7\u89c4\u8303\u5316\u8bbe\u8ba1\uff0c\u907f\u514d\u4e86\u5728\u501f\u9605\u8868\u4e2d\u91cd\u590d\u4fdd\u5b58\u8bfb\u8005\u59d3\u540d\u3001\u56fe\u4e66\u540d\u79f0\u7b49\u4fe1\u606f\uff0c\u51cf\u5c11\u4e86\u6570\u636e\u5197\u4f59\uff0c\u63d0\u9ad8\u4e86\u6570\u636e\u4e00\u81f4\u6027\u3002\u5728\u7269\u7406\u8bbe\u8ba1\u9636\u6bb5\uff0c\u6211\u4f7f\u7528 SQL \u521b\u5efa\u6570\u636e\u5e93\u548c\u6570\u636e\u8868\uff0c\u8bbe\u7f6e\u4e86\u4e3b\u952e\u3001\u5916\u952e\u3001\u975e\u7a7a\u3001\u9ed8\u8ba4\u503c\u548c CHECK \u7ea6\u675f\uff0c\u5bf9\u5b9e\u4f53\u5b8c\u6574\u6027\u3001\u53c2\u7167\u5b8c\u6574\u6027\u548c\u7528\u6237\u5b9a\u4e49\u5b8c\u6574\u6027\u6709\u4e86\u66f4\u6df1\u523b\u7684\u7406\u89e3\u3002
\u200b
\u5728\u6570\u636e\u64cd\u4f5c\u90e8\u5206\uff0c\u6211\u7ec3\u4e60\u4e86 INSERT\u3001UPDATE\u3001DELETE \u548c SELECT \u8bed\u53e5\uff0c\u5e76\u5b8c\u6210\u4e86\u57fa\u7840\u67e5\u8be2\u3001\u805a\u5408\u67e5\u8be2\u3001\u591a\u8868\u8fde\u63a5\u67e5\u8be2\u3001\u5d4c\u5957\u67e5\u8be2\u548c\u96c6\u5408\u67e5\u8be2\u7b49\u5185\u5bb9\u3002\u901a\u8fc7\u8fd9\u4e9b\u7ec3\u4e60\uff0c\u6211\u638c\u63e1\u4e86 SQL \u67e5\u8be2\u8bed\u53e5\u7684\u5e38\u89c1\u5199\u6cd5\uff0c\u5c24\u5176\u662f\u591a\u8868\u8fde\u63a5\u548c\u5d4c\u5957\u67e5\u8be2\u7684\u4f7f\u7528\u65b9\u6cd5\u3002\u5b9e\u9a8c\u4e2d\u8fd8\u521b\u5efa\u4e86\u89c6\u56fe\u548c\u7d22\u5f15\uff0c\u7406\u89e3\u4e86\u89c6\u56fe\u53ef\u4ee5\u7b80\u5316\u590d\u6742\u67e5\u8be2\uff0c\u7d22\u5f15\u53ef\u4ee5\u63d0\u9ad8\u67e5\u8be2\u6548\u7387\uff0c\u4f46\u4e5f\u4f1a\u589e\u52a0\u7ef4\u62a4\u6210\u672c\u3002
\u200b
\u5728\u89e6\u53d1\u5668\u90e8\u5206\uff0c\u6211\u5b9e\u73b0\u4e86\u501f\u4e66\u81ea\u52a8\u51cf\u5c11\u5e93\u5b58\u3001\u8fd8\u4e66\u81ea\u52a8\u589e\u52a0\u5e93\u5b58\u5e76\u8ba1\u7b97\u7f5a\u6b3e\u3001\u5220\u9664\u8bfb\u8005\u524d\u8bb0\u5f55\u65e5\u5fd7\u7b49\u529f\u80fd\u3002\u901a\u8fc7\u89e6\u53d1\u5668\u5b9e\u9a8c\uff0c\u6211\u8ba4\u8bc6\u5230\u6570\u636e\u5e93\u4e0d\u4ec5\u53ef\u4ee5\u5b58\u50a8\u6570\u636e\uff0c\u8fd8\u53ef\u4ee5\u5728\u7279\u5b9a\u64cd\u4f5c\u53d1\u751f\u65f6\u81ea\u52a8\u6267\u884c\u4e00\u4e9b\u4e1a\u52a1\u903b\u8f91\u3002\u5b9e\u9a8c\u8fc7\u7a0b\u4e2d\u4e5f\u9047\u5230\u4e86\u4e00\u4e9b\u95ee\u9898\uff0c\u4f8b\u5982\u5916\u952e\u7ea6\u675f\u5bfc\u81f4\u6570\u636e\u65e0\u6cd5\u5220\u9664\u3001CHECK \u7ea6\u675f\u63d2\u5165\u5931\u8d25\u3001\u89e6\u53d1\u5668\u8bed\u6cd5\u9519\u8bef\u7b49\u3002\u901a\u8fc7\u67e5\u770b\u9519\u8bef\u4fe1\u606f\u3001\u4fee\u6539 SQL \u8bed\u53e5\u548c\u53cd\u590d\u6d4b\u8bd5\uff0c\u6700\u7ec8\u89e3\u51b3\u4e86\u8fd9\u4e9b\u95ee\u9898\u3002
\u200b
\u901a\u8fc7\u672c\u6b21\u5b9e\u9a8c\uff0c\u6211\u4e0d\u4ec5\u5de9\u56fa\u4e86\u6570\u636e\u5e93\u7406\u8bba\u77e5\u8bc6\uff0c\u4e5f\u63d0\u9ad8\u4e86 SQL \u7f16\u5199\u80fd\u529b\u548c\u6570\u636e\u5e93\u8c03\u8bd5\u80fd\u529b\u3002\u4eca\u540e\u5728\u8bbe\u8ba1\u6570\u636e\u5e93\u7cfb\u7edf<\/pre>\n","protected":false},"excerpt":{"rendered":"\u6570\u636e\u5e93\u7efc\u5408\u5b9e\u9a8c 1.\u9700\u6c42\u5206\u6790 \u67d0\u5927\u578b\u56fe\u4e66\u9986\u9700\u8981\u5f00\u53d1\u4e00\u5957\u6570\u5b57\u5316\u501f\u9605\u7ba1\u7406\u7cfb\u7edf\uff0c\u4e3b\u8981\u4e1a\u52a1\u9700\u6c42\u5982\u4e0b\uff1a \u56fe\u4e66\u4fe1\u606f\uff1a\u8bb0\u5f55\u56fe […]<\/p>\n","protected":false},"author":1,"featured_media":448,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[9],"tags":[],"class_list":["post-446","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-wenzhang"],"_links":{"self":[{"href":"https:\/\/fg2025.cn\/index.php\/wp-json\/wp\/v2\/posts\/446","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/fg2025.cn\/index.php\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/fg2025.cn\/index.php\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/fg2025.cn\/index.php\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/fg2025.cn\/index.php\/wp-json\/wp\/v2\/comments?post=446"}],"version-history":[{"count":0,"href":"https:\/\/fg2025.cn\/index.php\/wp-json\/wp\/v2\/posts\/446\/revisions"}],"wp:attachment":[{"href":"https:\/\/fg2025.cn\/index.php\/wp-json\/wp\/v2\/media?parent=446"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/fg2025.cn\/index.php\/wp-json\/wp\/v2\/categories?post=446"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/fg2025.cn\/index.php\/wp-json\/wp\/v2\/tags?post=446"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}
CREATE VIEW v_unreturned AS
SELECT br.borrowid, r.rname, b.bname,
br.borrowdate, br.returndate
FROM borrow br
JOIN reader r ON br.rno = r.rno
JOIN book b ON br.bno = b.bno
WHERE br.actualdate IS NULL;
2.\u67e5\u8be2\u89c6\u56fe
SELECT * FROM v_unreturned;
3.\u521b\u5efa\u5b66\u751f\u8bfb\u8005\u89c6\u56fe\uff0c\u5e26 WITH CHECK OPTION
CREATE VIEW v_student_reader AS
SELECT *
FROM reader
WHERE dept LIKE '%\u5b66\u9662%'
WITH CHECK OPTION;
4.\u6d4b\u8bd5\u53ef\u66f4\u65b0\u89c6\u56fe
UPDATE v_student_reader
SET phone = '18800000000'
WHERE rno = 'R2024002';
\u8bf4\u660e\uff1a
\u8be5\u89c6\u56fe\u57fa\u4e8e\u5355\u8868 reader \u521b\u5efa\uff0c\u6ca1\u6709\u805a\u5408\u51fd\u6570\u3001\u5206\u7ec4\u548c\u8fde\u63a5\uff0c\u56e0\u6b64\u5c5e\u4e8e\u53ef\u66f4\u65b0\u89c6\u56fe\u3002
5.\u521b\u5efa\u4e0d\u53ef\u66f4\u65b0\u7684\u805a\u5408\u89c6\u56fe
CREATE VIEW v_press_count AS
SELECT press, COUNT(*) AS total
FROM book
GROUP BY press;
\u8bf4\u660e\uff1a
\u8be5\u89c6\u56fe\u4f7f\u7528\u4e86 GROUP BY \u548c COUNT \u805a\u5408\u51fd\u6570\uff0c\u56e0\u6b64\u4e00\u822c\u4e0d\u80fd\u76f4\u63a5\u66f4\u65b0\u3002
6.\u5220\u9664\u89c6\u56fe
DROP VIEW v_unreturned;
DROP VIEW v_student_reader;
DROP VIEW v_press_count;<\/pre>\n\n\n\n
12.\u7d22\u5f15<\/h2>\n\n\n\n1.\u521b\u5efa\u666e\u901a\u7d22\u5f15
CREATE INDEX idx_book_bname
ON book(bname);
2.\u521b\u5efa\u552f\u4e00\u7d22\u5f15
CREATE UNIQUE INDEX idx_reader_phone
ON reader(phone);
3.\u521b\u5efa\u590d\u5408\u7d22\u5f15
CREATE INDEX idx_borrow_rno_bno
ON borrow(rno,bno);
\u67e5\u770b\u7d22\u5f15
SHOW INDEX FROM book;
SHOW INDEX FROM reader;
SHOW INDEX FROM borrow;
\u5220\u9664\u7d22\u5f15
DROP INDEX idx_book_bname ON book;
DROP INDEX idx_reader_phone ON reader;
DROP INDEX idx_borrow_rno_bno ON borrow;<\/pre>\n\n\n\n13.\u6570\u636e\u5b8c\u6574\u6027\u7ea6\u675f\u9a8c\u8bc1\u4e0e\u7ea7\u8054\u64cd\u4f5c<\/h2>\n\n\n\n1.\u5b9e\u4f53\u5b8c\u6574\u6027\u9a8c\u8bc1\uff1a\u4e3b\u952e\u4e0d\u80fd\u4e3a\u7a7a
INSERT INTO book(bno,bname,author,press,pubyear,stock)
VALUES(NULL,'\u6d4b\u8bd5\u4e66','\u6d4b\u8bd5\u4f5c\u8005','\u6d4b\u8bd5\u51fa\u7248\u793e',2020,1);
\u8bf4\u660e\uff1a
bno \u662f book \u8868\u4e3b\u952e\uff0c\u4e3b\u952e\u4e0d\u80fd\u4e3a\u7a7a\uff0c\u56e0\u6b64\u63d2\u5165\u5931\u8d25\u3002
2.\u53c2\u7167\u5b8c\u6574\u6027\u9a8c\u8bc1\uff1a\u63d2\u5165\u4e0d\u5b58\u5728\u7684\u56fe\u4e66\u7f16\u53f7
INSERT INTO borrow(rno,bno,borrowdate,returndate,actualdate)
VALUES('R2024001','B999','2025-05-01','2025-05-15',NULL);
\u8bf4\u660e\uff1a
B999 \u5728 book \u8868\u4e2d\u4e0d\u5b58\u5728\uff0cborrow.bno \u662f\u5916\u952e\uff0c\u56e0\u6b64\u8fdd\u53cd\u53c2\u7167\u5b8c\u6574\u6027\u3002
3.\u7528\u6237\u5b9a\u4e49\u5b8c\u6574\u6027\u9a8c\u8bc1\uff1a\u5e93\u5b58\u4e0d\u80fd\u5c0f\u4e8e0
UPDATE book
SET stock = -1
WHERE bno = 'B001';
\u8bf4\u660e\uff1a
stock \u5b57\u6bb5\u8bbe\u7f6e\u4e86 CHECK(stock>=0)\uff0c\u5e93\u5b58\u4e0d\u80fd\u4e3a\u8d1f\u6570\u3002
4.\u7528\u6237\u5b9a\u4e49\u5b8c\u6574\u6027\u9a8c\u8bc1\uff1a\u5e93\u5b58\u4e0d\u80fd\u5c0f\u4e8e0
UPDATE book
SET stock = -1
WHERE bno = 'B001';
\u8bf4\u660e\uff1a
stock \u5b57\u6bb5\u8bbe\u7f6e\u4e86 CHECK(stock>=0)\uff0c\u5e93\u5b58\u4e0d\u80fd\u4e3a\u8d1f\u6570\u3002
5.ON UPDATE CASCADE \u6d4b\u8bd5
UPDATE reader
SET rno = 'R2024999'
WHERE rno = 'R2024003';
SELECT * FROM borrow
WHERE rno = 'R2024999';
\u8bf4\u660e\uff1a
reader.rno \u66f4\u65b0\u540e\uff0cborrow \u8868\u4e2d\u5bf9\u5e94\u7684\u5916\u952e rno \u4f1a\u81ea\u52a8\u540c\u6b65\u66f4\u65b0\u3002<\/pre>\n\n\n\n14.\u89e6\u53d1\u5668<\/h2>\n\n\n\n\u51c6\u5907\uff1a\u5220\u9664\u65e7\u89e6\u53d1\u5668
DROP TRIGGER IF EXISTS trg_borrow_before_insert;
DROP TRIGGER IF EXISTS trg_return_after_update;
DROP TRIGGER IF EXISTS trg_reader_before_delete;
\u521b\u5efa\u5220\u9664\u8bfb\u8005\u65e5\u5fd7\u8868
CREATE TABLE reader_delete_log(
logid INT AUTO_INCREMENT PRIMARY KEY,
rno CHAR(12),
rname VARCHAR(20),
dept VARCHAR(40),
delete_time DATETIME DEFAULT CURRENT_TIMESTAMP
);
1.\u501f\u4e66\u65f6\u81ea\u52a8\u51cf\u5c11\u5e93\u5b58
DELIMITER \/\/
CREATE TRIGGER trg_borrow_before_insert
BEFORE INSERT ON borrow
FOR EACH ROW
BEGIN
DECLARE v_stock INT;
SELECT stock INTO v_stock
FROM book
WHERE bno = NEW.bno;
IF v_stock <= 0 THEN
SIGNAL SQLSTATE '45000'
SET MESSAGE_TEXT = '\u5e93\u5b58\u4e0d\u8db3\uff0c\u4e0d\u80fd\u501f\u4e66';
ELSE
UPDATE book
SET stock = stock - 1
WHERE bno = NEW.bno;
END IF;
END \/\/
DELIMITER ;
\u6d4b\u8bd5\uff1a
SELECT stock FROM book WHERE bno='B003';
INSERT INTO borrow(rno,bno,borrowdate,returndate,actualdate)
VALUES('R2024002','B003','2025-05-01','2025-05-15',NULL);
SELECT stock FROM book WHERE bno='B003';
2.\u8fd8\u4e66\u65f6\u81ea\u52a8\u589e\u52a0\u5e93\u5b58\u5e76\u8ba1\u7b97\u7f5a\u6b3e
DELIMITER \/\/
CREATE TRIGGER trg_return_after_update
AFTER UPDATE ON borrow
FOR EACH ROW
BEGIN
IF OLD.actualdate IS NULL AND NEW.actualdate IS NOT NULL THEN
UPDATE book
SET stock = stock + 1
WHERE bno = NEW.bno;
UPDATE borrow
SET fine =
CASE
WHEN NEW.actualdate > NEW.returndate
THEN DATEDIFF(NEW.actualdate, NEW.returndate) * 1
ELSE 0
END
WHERE borrowid = NEW.borrowid;
END IF;
END \/\/
DELIMITER ;
\u6d4b\u8bd5\uff1a
UPDATE borrow
SET actualdate = '2025-05-18'
WHERE rno='R2024002'
AND bno='B003'
AND borrowdate='2025-05-01';
SELECT * FROM borrow
WHERE rno='R2024002'
AND bno='B003';
SELECT stock FROM book WHERE bno='B003';
3.\u5220\u9664\u8bfb\u8005\u524d\u8bb0\u5f55\u65e5\u5fd7
DELIMITER \/\/
CREATE TRIGGER trg_reader_before_delete
BEFORE DELETE ON reader
FOR EACH ROW
BEGIN
INSERT INTO reader_delete_log(rno,rname,dept)
VALUES(OLD.rno, OLD.rname, OLD.dept);
END \/\/
DELIMITER ;
\u6d4b\u8bd5\uff1a
INSERT INTO reader
VALUES('R2024888','\u65e5\u5fd7\u6d4b\u8bd5','\u7537','\u6d4b\u8bd5\u5b66\u9662','\u65e0');
DELETE FROM reader
WHERE rno='R2024888';
SELECT * FROM reader_delete_log;<\/pre>\n\n\n\n15.\u6570\u636e\u5b89\u5168\u6027<\/h2>\n\n\n\n1.\u521b\u5efa\u7528\u6237\u5e76\u6388\u4e88\u67e5\u8be2\u6743\u9650
CREATE USER 'lib_user1'@'localhost'
IDENTIFIED BY '123456';
GRANT SELECT
ON library_db.book
TO 'lib_user1'@'localhost';
\u67e5\u770b\u6743\u9650\uff1a
SHOW GRANTS FOR 'lib_user1'@'localhost';
2.\u6388\u4e88\u6743\u9650\u5e76\u5141\u8bb8\u8f6c\u6388\u6743
GRANT SELECT, INSERT
ON library_db.reader
TO 'lib_user1'@'localhost'
WITH GRANT OPTION;
\u8bf4\u660e\uff1a
WITH GRANT OPTION \u8868\u793a\u8be5\u7528\u6237\u53ef\u4ee5\u5c06\u81ea\u5df1\u62e5\u6709\u7684\u6743\u9650\u518d\u6388\u4e88\u5176\u4ed6\u7528\u6237\u3002
3.\u56de\u6536\u6743\u9650
REVOKE INSERT
ON library_db.reader
FROM 'lib_user1'@'localhost';
4.\u521b\u5efa\u89d2\u8272\u5e76\u6388\u6743
CREATE ROLE 'reader_role';
GRANT SELECT
ON library_db.*
TO 'reader_role';
CREATE USER 'lib_user2'@'localhost'
IDENTIFIED BY '123456';
GRANT 'reader_role'
TO 'lib_user2'@'localhost';
SET DEFAULT ROLE 'reader_role'
TO 'lib_user2'@'localhost';<\/pre>\n\n\n\n16.\u89c6\u56fe\u4e0e\u6d3e\u751f\u8868<\/h2>\n\n\n\n1.\u5e26\u805a\u5408\u51fd\u6570\u7684\u89c6\u56fe\uff1a\u7edf\u8ba1\u6bcf\u4e2a\u8bfb\u8005\u501f\u9605\u6b21\u6570
CREATE VIEW v_reader_borrow_count AS
SELECT r.rno, r.rname, COUNT(br.borrowid) AS borrow_count
FROM reader r
LEFT JOIN borrow br
ON r.rno = br.rno
GROUP BY r.rno, r.rname;
\u67e5\u8be2\uff1a
SELECT * FROM v_reader_borrow_count;
2.\u6d3e\u751f\u8868\uff1a\u67e5\u8be2\u501f\u9605\u6b21\u6570\u5927\u4e8e1\u7684\u8bfb\u8005
SELECT *
FROM (
SELECT rno, COUNT(*) AS borrow_count
FROM borrow
GROUP BY rno
) AS t
WHERE t.borrow_count > 1;
3.WITH \u5b50\u53e5\u7edf\u8ba1\u6bcf\u4f4d\u8bfb\u8005\u501f\u9605\u6570\u91cf
WITH reader_count AS (
SELECT rno, COUNT(*) AS total
FROM borrow
GROUP BY rno
)
SELECT r.rno, r.rname, rc.total
FROM reader r
LEFT JOIN reader_count rc
ON r.rno = rc.rno;
4.WITH \u5b50\u53e5\uff1a\u67e5\u8be2\u672a\u5f52\u8fd8\u56fe\u4e66
WITH unreturned AS (
SELECT br.borrowid, r.rname, b.bname,
br.borrowdate, br.returndate
FROM borrow br
JOIN reader r ON br.rno = r.rno
JOIN book b ON br.bno = b.bno
WHERE br.actualdate IS NULL
)
SELECT * FROM unreturned;<\/pre>\n\n\n\n17.\u6269\u5c55\u601d\u8003<\/h2>\n\n\n\n\n- \u5982\u4f55\u5904\u7406\u5206\u7c7b\u5b9e\u4f53\u7684\u81ea\u5173\u8054\uff1f<\/li>\n<\/ol>\n\n\n\n
\u5206\u7c7b\u5b9e\u4f53\u5b58\u5728\u201c\u4e0a\u7ea7\u5206\u7c7b\u201d\u548c\u201c\u4e0b\u7ea7\u5206\u7c7b\u201d\u7684\u5173\u7cfb\uff0c\u56e0\u6b64\u53ef\u4ee5\u5728 category \u8868\u4e2d\u8bbe\u7f6e parentid \u5b57\u6bb5\u3002
category(
cid,
cname,
parentid
)
\u5176\u4e2d cid \u662f\u5206\u7c7b\u7f16\u53f7\uff0cparentid \u662f\u4e0a\u7ea7\u5206\u7c7b\u7f16\u53f7\uff0c\u540c\u65f6 parentid \u4e5f\u662f\u6307\u5411 category.cid \u7684\u5916\u952e\u3002
\u5982\u679c\u67d0\u5206\u7c7b\u6ca1\u6709\u4e0a\u7ea7\u5206\u7c7b\uff0c\u5219 parentid \u53ef\u4ee5\u4e3a\u7a7a\u3002
\u8fd9\u79cd\u8bbe\u8ba1\u53ef\u4ee5\u8868\u793a\u6811\u5f62\u7ed3\u6784\uff0c\u4f8b\u5982\uff1a
\u56fe\u4e66
\u251c\u2500\u2500 \u8ba1\u7b97\u673a
\u2502 \u251c\u2500\u2500 \u6570\u636e\u5e93
\u2502 \u2514\u2500\u2500 \u7f51\u7edc\u6280\u672f
\u2514\u2500\u2500 \u6587\u5b66
\u2514\u2500\u2500 \u79d1\u5e7b\u5c0f\u8bf4<\/pre>\n\n\n\n
\n\n\n\n2. \u501f\u9605\u5173\u7cfb\u662f\u5426\u53ef\u80fd\u5b58\u5728\u6570\u636e\u5197\u4f59\uff1f<\/h2>\n\n\n\n\u501f\u9605\u8868\u5982\u679c\u53ea\u4fdd\u5b58 rno\u3001bno\u3001borrowdate\u3001returndate\u3001actualdate \u7b49\u4fe1\u606f\uff0c\u5219\u5197\u4f59\u8f83\u5c11\u3002
\u4f46\u662f\u5982\u679c\u5728 borrow \u8868\u4e2d\u540c\u65f6\u4fdd\u5b58\u8bfb\u8005\u59d3\u540d rname\u3001\u56fe\u4e66\u540d\u79f0 bname\u3001\u51fa\u7248\u793e press \u7b49\u4fe1\u606f\uff0c\u5c31\u4f1a\u4ea7\u751f\u6570\u636e\u5197\u4f59\u3002
\u4f8b\u5982\uff1a
borrow(borrowid, rno, rname, bno, bname, borrowdate)
\u5176\u4e2d rname \u4f9d\u8d56 rno\uff0cbname \u4f9d\u8d56 bno\uff0c\u800c\u4e0d\u662f\u76f4\u63a5\u4f9d\u8d56 borrowid\uff0c\u4f1a\u4ea7\u751f\u4f20\u9012\u4f9d\u8d56\u3002
\u89c4\u8303\u5316\u65b9\u6848\uff1a
\u5c06\u8bfb\u8005\u4fe1\u606f\u4fdd\u5b58\u5728 reader \u8868\uff1b
\u5c06\u56fe\u4e66\u4fe1\u606f\u4fdd\u5b58\u5728 book \u8868\uff1b
borrow \u8868\u53ea\u4fdd\u5b58\u8bfb\u8005\u8bc1\u53f7\u548c\u56fe\u4e66\u7f16\u53f7\u4f5c\u4e3a\u5916\u952e\u3002<\/pre>\n\n\n\n
\n\n\n\n3. \u5982\u4f55\u9632\u6b62\u5e93\u5b58\u4e3a\u8d1f\u6570\uff1f<\/h2>\n\n\n\n\u53ef\u4ee5\u4ece\u4e24\u4e2a\u65b9\u9762\u9632\u6b62\u5e93\u5b58\u4e3a\u8d1f\u6570\uff1a
\u7b2c\u4e00\uff0c\u5728 book \u8868\u4e2d\u8bbe\u7f6e CHECK(stock >= 0) \u7ea6\u675f\uff0c\u4fdd\u8bc1\u5e93\u5b58\u4e0d\u80fd\u5c0f\u4e8e0\u3002
\u7b2c\u4e8c\uff0c\u5728\u501f\u4e66\u89e6\u53d1\u5668\u4e2d\u5224\u65ad\u5e93\u5b58\u6570\u91cf\u3002
\u5f53\u63d2\u5165 borrow \u501f\u9605\u8bb0\u5f55\u65f6\uff0c\u5148\u67e5\u8be2\u56fe\u4e66\u5e93\u5b58\u3002
\u5982\u679c\u5e93\u5b58\u5c0f\u4e8e\u7b49\u4e8e0\uff0c\u5219\u4f7f\u7528 SIGNAL \u629b\u51fa\u9519\u8bef\uff0c\u963b\u6b62\u501f\u4e66\u64cd\u4f5c\uff1b
\u5982\u679c\u5e93\u5b58\u5927\u4e8e0\uff0c\u5219\u5141\u8bb8\u501f\u9605\uff0c\u5e76\u81ea\u52a8\u5c06\u5e93\u5b58\u51cf1\u3002
\u8fd9\u6837\u53ef\u4ee5\u4fdd\u8bc1\u501f\u4e66\u65f6\u4e0d\u4f1a\u51fa\u73b0\u5e93\u5b58\u4e3a\u8d1f\u6570\u7684\u60c5\u51b5\u3002<\/pre>\n\n\n\n
\n\n\n\n4. \u9884\u7ea6\u56fe\u4e66\u529f\u80fd\u9700\u8981\u589e\u52a0\u54ea\u4e9b\u5b9e\u4f53\u548c\u5173\u7cfb\uff1f<\/h2>\n\n\n\n\u5982\u679c\u7cfb\u7edf\u652f\u6301\u9884\u7ea6\u56fe\u4e66\u529f\u80fd\uff0c\u53ef\u4ee5\u589e\u52a0 reservation \u9884\u7ea6\u8868\u3002
reservation(
reserveid,
rno,
bno,
reservedate,
status
)
\u5176\u4e2d\uff1a
reserveid \u8868\u793a\u9884\u7ea6\u7f16\u53f7\uff1b
rno \u662f\u8bfb\u8005\u8bc1\u53f7\uff0c\u5916\u952e\u5f15\u7528 reader.rno\uff1b
bno \u662f\u56fe\u4e66\u7f16\u53f7\uff0c\u5916\u952e\u5f15\u7528 book.bno\uff1b
reservedate \u8868\u793a\u9884\u7ea6\u65e5\u671f\uff1b
status \u8868\u793a\u9884\u7ea6\u72b6\u6001\uff0c\u5982\u201c\u9884\u7ea6\u4e2d\u201d\u201c\u5df2\u53d6\u6d88\u201d\u201c\u5df2\u5b8c\u6210\u201d\u3002
\u65b0\u589e\u5173\u7cfb\uff1a
\u4e00\u4e2a\u8bfb\u8005\u53ef\u4ee5\u9884\u7ea6\u591a\u672c\u56fe\u4e66\uff1b
\u4e00\u672c\u56fe\u4e66\u53ef\u4ee5\u88ab\u591a\u4e2a\u8bfb\u8005\u9884\u7ea6\uff1b
\u8bfb\u8005\u548c\u56fe\u4e66\u4e4b\u95f4\u901a\u8fc7 reservation \u8868\u5f62\u6210 m:n \u8054\u7cfb\u3002<\/pre>\n\n\n\n
\n\n\n\n5. \u4e3a\u4ec0\u4e48\u9075\u5faa\u6700\u5c0f\u6743\u9650\u539f\u5219\uff1f<\/h2>\n\n\n\n\u6700\u5c0f\u6743\u9650\u539f\u5219\u662f\u6307\u53ea\u7ed9\u7528\u6237\u5b8c\u6210\u5de5\u4f5c\u6240\u5fc5\u9700\u7684\u6743\u9650\uff0c\u4e0d\u6388\u4e88\u591a\u4f59\u6743\u9650\u3002
\u5728\u672c\u5b9e\u9a8c\u4e2d\uff0c\u5982\u679c\u67d0\u7528\u6237\u53ea\u8d1f\u8d23\u67e5\u8be2\u56fe\u4e66\u4fe1\u606f\uff0c\u5219\u53ea\u6388\u4e88 SELECT \u6743\u9650\u5373\u53ef\uff0c\u4e0d\u5e94\u8be5\u6388\u4e88 INSERT\u3001UPDATE\u3001DELETE \u7b49\u6743\u9650\u3002
\u4f8b\u5982\uff1a
GRANT SELECT ON library_db.book TO 'lib_user1'@'localhost';
\u8fd9\u6837\u53ef\u4ee5\u9632\u6b62\u7528\u6237\u8bef\u5220\u3001\u8bef\u6539\u6570\u636e\uff0c\u63d0\u9ad8\u6570\u636e\u5e93\u5b89\u5168\u6027\u3002
\u5982\u679c\u540e\u7eed\u4e0d\u518d\u9700\u8981\u67d0\u9879\u6743\u9650\uff0c\u8fd8\u53ef\u4ee5\u4f7f\u7528 REVOKE \u56de\u6536\u6743\u9650\u3002<\/pre>\n\n\n\n
\n\n\n\n6. \u5e76\u53d1\u501f\u9605\u5e93\u5b58\u4ec5\u52691\u672c\u7684\u56fe\u4e66\u4f1a\u4ea7\u751f\u4ec0\u4e48\u95ee\u9898\uff1f\u5982\u4f55\u89e3\u51b3\uff1f<\/h2>\n\n\n\n\u5f53\u591a\u7528\u6237\u540c\u65f6\u501f\u9605\u540c\u4e00\u672c\u5e93\u5b58\u4ec5\u52691\u672c\u7684\u56fe\u4e66\u65f6\uff0c\u53ef\u80fd\u51fa\u73b0\u8d85\u5356\u95ee\u9898\u3002
\u4f8b\u5982\u4e24\u4e2a\u7528\u6237\u540c\u65f6\u8bfb\u53d6\u5e93\u5b58 stock=1\uff0c\u90fd\u8ba4\u4e3a\u53ef\u4ee5\u501f\u9605\uff0c\u7136\u540e\u540c\u65f6\u63d2\u5165\u501f\u9605\u8bb0\u5f55\u5e76\u6267\u884c\u5e93\u5b58\u51cf1\uff0c\u6700\u7ec8\u53ef\u80fd\u5bfc\u81f4\u5e93\u5b58\u5f02\u5e38\u6216\u51fa\u73b0\u8d85\u989d\u501f\u9605\u3002
\u89e3\u51b3\u65b9\u6cd5\uff1a
1. \u4f7f\u7528\u4e8b\u52a1\u4fdd\u8bc1\u501f\u4e66\u64cd\u4f5c\u7684\u539f\u5b50\u6027\uff1b
2. \u4f7f\u7528 SELECT ... FOR UPDATE \u5bf9\u56fe\u4e66\u5e93\u5b58\u8bb0\u5f55\u52a0\u884c\u7ea7\u9501\uff1b
3. \u5728\u89e6\u53d1\u5668\u4e2d\u5224\u65ad\u5e93\u5b58\u662f\u5426\u5927\u4e8e0\uff1b
4. \u7ed9 stock \u5b57\u6bb5\u8bbe\u7f6e CHECK(stock >= 0) \u7ea6\u675f\u3002
\u793a\u4f8b\uff1a
START TRANSACTION;
SELECT stock
FROM book
WHERE bno='B001'
FOR UPDATE;
UPDATE book
SET stock = stock - 1
WHERE bno='B001'
AND stock > 0;
INSERT INTO borrow(rno,bno,borrowdate,returndate)
VALUES('R2024001','B001','2025-05-01','2025-05-15');
COMMIT;
\u8fd9\u6837\u53ef\u4ee5\u907f\u514d\u591a\u4e2a\u7528\u6237\u540c\u65f6\u4fee\u6539\u5e93\u5b58\u5bfc\u81f4\u6570\u636e\u4e0d\u4e00\u81f4\u3002<\/pre>\n\n\n\n
\n\n\n\n\u5b9e\u9a8c\u603b\u7ed3<\/h1>\n\n\n\n \u901a\u8fc7\u672c\u6b21\u56fe\u4e66\u501f\u9605\u7ba1\u7406\u7cfb\u7edf\u7efc\u5408\u5b9e\u9a8c\uff0c\u6211\u7cfb\u7edf\u5730\u5b8c\u6210\u4e86\u6570\u636e\u5e93\u8bbe\u8ba1\u4e0e\u5b9e\u73b0\u7684\u5168\u8fc7\u7a0b\u3002\u5b9e\u9a8c\u4ece\u9700\u6c42\u5206\u6790\u5f00\u59cb\uff0c\u9010\u6b65\u5b8c\u6210 E-R \u56fe\u8bbe\u8ba1\u3001\u5173\u7cfb\u6a21\u5f0f\u8f6c\u6362\u3001\u7269\u7406\u8868\u7ed3\u6784\u8bbe\u8ba1\u3001\u6570\u636e\u63d2\u5165\u3001\u67e5\u8be2\u64cd\u4f5c\u3001\u89c6\u56fe\u3001\u7d22\u5f15\u3001\u5b8c\u6574\u6027\u7ea6\u675f\u3001\u89e6\u53d1\u5668\u548c\u6743\u9650\u7ba1\u7406\u7b49\u5185\u5bb9\uff0c\u4f7f\u6211\u5bf9\u6570\u636e\u5e93\u5e94\u7528\u7cfb\u7edf\u7684\u8bbe\u8ba1\u6d41\u7a0b\u6709\u4e86\u66f4\u52a0\u5b8c\u6574\u7684\u8ba4\u8bc6\u3002
\u200b
\u5728\u5b9e\u9a8c\u8fc7\u7a0b\u4e2d\uff0c\u6211\u9996\u5148\u6839\u636e\u56fe\u4e66\u9986\u4e1a\u52a1\u9700\u6c42\u5206\u6790\u51fa\u56fe\u4e66\u3001\u8bfb\u8005\u3001\u501f\u9605\u3001\u51fa\u7248\u793e\u3001\u5206\u7c7b\u7b49\u5b9e\u4f53\uff0c\u5e76\u660e\u786e\u4e86\u5b83\u4eec\u4e4b\u95f4\u7684\u8054\u7cfb\u7c7b\u578b\u3002\u4f8b\u5982\uff0c\u51fa\u7248\u793e\u4e0e\u56fe\u4e66\u4e4b\u95f4\u662f\u4e00\u5bf9\u591a\u5173\u7cfb\uff0c\u5206\u7c7b\u4e0e\u56fe\u4e66\u4e4b\u95f4\u662f\u4e00\u5bf9\u591a\u5173\u7cfb\uff0c\u8bfb\u8005\u4e0e\u56fe\u4e66\u4e4b\u95f4\u901a\u8fc7\u501f\u9605\u8868\u5f62\u6210\u591a\u5bf9\u591a\u5173\u7cfb\u3002\u901a\u8fc7 E-R \u56fe\u8bbe\u8ba1\uff0c\u6211\u8fdb\u4e00\u6b65\u7406\u89e3\u4e86\u6982\u5ff5\u7ed3\u6784\u8bbe\u8ba1\u5728\u6570\u636e\u5e93\u5f00\u53d1\u4e2d\u7684\u91cd\u8981\u4f5c\u7528\u3002
\u200b
\u5728\u903b\u8f91\u7ed3\u6784\u8bbe\u8ba1\u9636\u6bb5\uff0c\u6211\u5c06 E-R \u56fe\u8f6c\u6362\u4e3a\u5173\u7cfb\u6a21\u5f0f\uff0c\u5e76\u5206\u6790\u5404\u8868\u662f\u5426\u6ee1\u8db3\u7b2c\u4e09\u8303\u5f0f\u3002\u901a\u8fc7\u89c4\u8303\u5316\u8bbe\u8ba1\uff0c\u907f\u514d\u4e86\u5728\u501f\u9605\u8868\u4e2d\u91cd\u590d\u4fdd\u5b58\u8bfb\u8005\u59d3\u540d\u3001\u56fe\u4e66\u540d\u79f0\u7b49\u4fe1\u606f\uff0c\u51cf\u5c11\u4e86\u6570\u636e\u5197\u4f59\uff0c\u63d0\u9ad8\u4e86\u6570\u636e\u4e00\u81f4\u6027\u3002\u5728\u7269\u7406\u8bbe\u8ba1\u9636\u6bb5\uff0c\u6211\u4f7f\u7528 SQL \u521b\u5efa\u6570\u636e\u5e93\u548c\u6570\u636e\u8868\uff0c\u8bbe\u7f6e\u4e86\u4e3b\u952e\u3001\u5916\u952e\u3001\u975e\u7a7a\u3001\u9ed8\u8ba4\u503c\u548c CHECK \u7ea6\u675f\uff0c\u5bf9\u5b9e\u4f53\u5b8c\u6574\u6027\u3001\u53c2\u7167\u5b8c\u6574\u6027\u548c\u7528\u6237\u5b9a\u4e49\u5b8c\u6574\u6027\u6709\u4e86\u66f4\u6df1\u523b\u7684\u7406\u89e3\u3002
\u200b
\u5728\u6570\u636e\u64cd\u4f5c\u90e8\u5206\uff0c\u6211\u7ec3\u4e60\u4e86 INSERT\u3001UPDATE\u3001DELETE \u548c SELECT \u8bed\u53e5\uff0c\u5e76\u5b8c\u6210\u4e86\u57fa\u7840\u67e5\u8be2\u3001\u805a\u5408\u67e5\u8be2\u3001\u591a\u8868\u8fde\u63a5\u67e5\u8be2\u3001\u5d4c\u5957\u67e5\u8be2\u548c\u96c6\u5408\u67e5\u8be2\u7b49\u5185\u5bb9\u3002\u901a\u8fc7\u8fd9\u4e9b\u7ec3\u4e60\uff0c\u6211\u638c\u63e1\u4e86 SQL \u67e5\u8be2\u8bed\u53e5\u7684\u5e38\u89c1\u5199\u6cd5\uff0c\u5c24\u5176\u662f\u591a\u8868\u8fde\u63a5\u548c\u5d4c\u5957\u67e5\u8be2\u7684\u4f7f\u7528\u65b9\u6cd5\u3002\u5b9e\u9a8c\u4e2d\u8fd8\u521b\u5efa\u4e86\u89c6\u56fe\u548c\u7d22\u5f15\uff0c\u7406\u89e3\u4e86\u89c6\u56fe\u53ef\u4ee5\u7b80\u5316\u590d\u6742\u67e5\u8be2\uff0c\u7d22\u5f15\u53ef\u4ee5\u63d0\u9ad8\u67e5\u8be2\u6548\u7387\uff0c\u4f46\u4e5f\u4f1a\u589e\u52a0\u7ef4\u62a4\u6210\u672c\u3002
\u200b
\u5728\u89e6\u53d1\u5668\u90e8\u5206\uff0c\u6211\u5b9e\u73b0\u4e86\u501f\u4e66\u81ea\u52a8\u51cf\u5c11\u5e93\u5b58\u3001\u8fd8\u4e66\u81ea\u52a8\u589e\u52a0\u5e93\u5b58\u5e76\u8ba1\u7b97\u7f5a\u6b3e\u3001\u5220\u9664\u8bfb\u8005\u524d\u8bb0\u5f55\u65e5\u5fd7\u7b49\u529f\u80fd\u3002\u901a\u8fc7\u89e6\u53d1\u5668\u5b9e\u9a8c\uff0c\u6211\u8ba4\u8bc6\u5230\u6570\u636e\u5e93\u4e0d\u4ec5\u53ef\u4ee5\u5b58\u50a8\u6570\u636e\uff0c\u8fd8\u53ef\u4ee5\u5728\u7279\u5b9a\u64cd\u4f5c\u53d1\u751f\u65f6\u81ea\u52a8\u6267\u884c\u4e00\u4e9b\u4e1a\u52a1\u903b\u8f91\u3002\u5b9e\u9a8c\u8fc7\u7a0b\u4e2d\u4e5f\u9047\u5230\u4e86\u4e00\u4e9b\u95ee\u9898\uff0c\u4f8b\u5982\u5916\u952e\u7ea6\u675f\u5bfc\u81f4\u6570\u636e\u65e0\u6cd5\u5220\u9664\u3001CHECK \u7ea6\u675f\u63d2\u5165\u5931\u8d25\u3001\u89e6\u53d1\u5668\u8bed\u6cd5\u9519\u8bef\u7b49\u3002\u901a\u8fc7\u67e5\u770b\u9519\u8bef\u4fe1\u606f\u3001\u4fee\u6539 SQL \u8bed\u53e5\u548c\u53cd\u590d\u6d4b\u8bd5\uff0c\u6700\u7ec8\u89e3\u51b3\u4e86\u8fd9\u4e9b\u95ee\u9898\u3002
\u200b
\u901a\u8fc7\u672c\u6b21\u5b9e\u9a8c\uff0c\u6211\u4e0d\u4ec5\u5de9\u56fa\u4e86\u6570\u636e\u5e93\u7406\u8bba\u77e5\u8bc6\uff0c\u4e5f\u63d0\u9ad8\u4e86 SQL \u7f16\u5199\u80fd\u529b\u548c\u6570\u636e\u5e93\u8c03\u8bd5\u80fd\u529b\u3002\u4eca\u540e\u5728\u8bbe\u8ba1\u6570\u636e\u5e93\u7cfb\u7edf<\/pre>\n","protected":false},"excerpt":{"rendered":"\u6570\u636e\u5e93\u7efc\u5408\u5b9e\u9a8c 1.\u9700\u6c42\u5206\u6790 \u67d0\u5927\u578b\u56fe\u4e66\u9986\u9700\u8981\u5f00\u53d1\u4e00\u5957\u6570\u5b57\u5316\u501f\u9605\u7ba1\u7406\u7cfb\u7edf\uff0c\u4e3b\u8981\u4e1a\u52a1\u9700\u6c42\u5982\u4e0b\uff1a \u56fe\u4e66\u4fe1\u606f\uff1a\u8bb0\u5f55\u56fe […]<\/p>\n","protected":false},"author":1,"featured_media":448,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[9],"tags":[],"class_list":["post-446","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-wenzhang"],"_links":{"self":[{"href":"https:\/\/fg2025.cn\/index.php\/wp-json\/wp\/v2\/posts\/446","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/fg2025.cn\/index.php\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/fg2025.cn\/index.php\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/fg2025.cn\/index.php\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/fg2025.cn\/index.php\/wp-json\/wp\/v2\/comments?post=446"}],"version-history":[{"count":0,"href":"https:\/\/fg2025.cn\/index.php\/wp-json\/wp\/v2\/posts\/446\/revisions"}],"wp:attachment":[{"href":"https:\/\/fg2025.cn\/index.php\/wp-json\/wp\/v2\/media?parent=446"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/fg2025.cn\/index.php\/wp-json\/wp\/v2\/categories?post=446"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/fg2025.cn\/index.php\/wp-json\/wp\/v2\/tags?post=446"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}
CREATE INDEX idx_book_bname
ON book(bname);
2.\u521b\u5efa\u552f\u4e00\u7d22\u5f15
CREATE UNIQUE INDEX idx_reader_phone
ON reader(phone);
3.\u521b\u5efa\u590d\u5408\u7d22\u5f15
CREATE INDEX idx_borrow_rno_bno
ON borrow(rno,bno);
\u67e5\u770b\u7d22\u5f15
SHOW INDEX FROM book;
SHOW INDEX FROM reader;
SHOW INDEX FROM borrow;
\u5220\u9664\u7d22\u5f15
DROP INDEX idx_book_bname ON book;
DROP INDEX idx_reader_phone ON reader;
DROP INDEX idx_borrow_rno_bno ON borrow;<\/pre>\n\n\n\n
13.\u6570\u636e\u5b8c\u6574\u6027\u7ea6\u675f\u9a8c\u8bc1\u4e0e\u7ea7\u8054\u64cd\u4f5c<\/h2>\n\n\n\n1.\u5b9e\u4f53\u5b8c\u6574\u6027\u9a8c\u8bc1\uff1a\u4e3b\u952e\u4e0d\u80fd\u4e3a\u7a7a
INSERT INTO book(bno,bname,author,press,pubyear,stock)
VALUES(NULL,'\u6d4b\u8bd5\u4e66','\u6d4b\u8bd5\u4f5c\u8005','\u6d4b\u8bd5\u51fa\u7248\u793e',2020,1);
\u8bf4\u660e\uff1a
bno \u662f book \u8868\u4e3b\u952e\uff0c\u4e3b\u952e\u4e0d\u80fd\u4e3a\u7a7a\uff0c\u56e0\u6b64\u63d2\u5165\u5931\u8d25\u3002
2.\u53c2\u7167\u5b8c\u6574\u6027\u9a8c\u8bc1\uff1a\u63d2\u5165\u4e0d\u5b58\u5728\u7684\u56fe\u4e66\u7f16\u53f7
INSERT INTO borrow(rno,bno,borrowdate,returndate,actualdate)
VALUES('R2024001','B999','2025-05-01','2025-05-15',NULL);
\u8bf4\u660e\uff1a
B999 \u5728 book \u8868\u4e2d\u4e0d\u5b58\u5728\uff0cborrow.bno \u662f\u5916\u952e\uff0c\u56e0\u6b64\u8fdd\u53cd\u53c2\u7167\u5b8c\u6574\u6027\u3002
3.\u7528\u6237\u5b9a\u4e49\u5b8c\u6574\u6027\u9a8c\u8bc1\uff1a\u5e93\u5b58\u4e0d\u80fd\u5c0f\u4e8e0
UPDATE book
SET stock = -1
WHERE bno = 'B001';
\u8bf4\u660e\uff1a
stock \u5b57\u6bb5\u8bbe\u7f6e\u4e86 CHECK(stock>=0)\uff0c\u5e93\u5b58\u4e0d\u80fd\u4e3a\u8d1f\u6570\u3002
4.\u7528\u6237\u5b9a\u4e49\u5b8c\u6574\u6027\u9a8c\u8bc1\uff1a\u5e93\u5b58\u4e0d\u80fd\u5c0f\u4e8e0
UPDATE book
SET stock = -1
WHERE bno = 'B001';
\u8bf4\u660e\uff1a
stock \u5b57\u6bb5\u8bbe\u7f6e\u4e86 CHECK(stock>=0)\uff0c\u5e93\u5b58\u4e0d\u80fd\u4e3a\u8d1f\u6570\u3002
5.ON UPDATE CASCADE \u6d4b\u8bd5
UPDATE reader
SET rno = 'R2024999'
WHERE rno = 'R2024003';
SELECT * FROM borrow
WHERE rno = 'R2024999';
\u8bf4\u660e\uff1a
reader.rno \u66f4\u65b0\u540e\uff0cborrow \u8868\u4e2d\u5bf9\u5e94\u7684\u5916\u952e rno \u4f1a\u81ea\u52a8\u540c\u6b65\u66f4\u65b0\u3002<\/pre>\n\n\n\n14.\u89e6\u53d1\u5668<\/h2>\n\n\n\n\u51c6\u5907\uff1a\u5220\u9664\u65e7\u89e6\u53d1\u5668
DROP TRIGGER IF EXISTS trg_borrow_before_insert;
DROP TRIGGER IF EXISTS trg_return_after_update;
DROP TRIGGER IF EXISTS trg_reader_before_delete;
\u521b\u5efa\u5220\u9664\u8bfb\u8005\u65e5\u5fd7\u8868
CREATE TABLE reader_delete_log(
logid INT AUTO_INCREMENT PRIMARY KEY,
rno CHAR(12),
rname VARCHAR(20),
dept VARCHAR(40),
delete_time DATETIME DEFAULT CURRENT_TIMESTAMP
);
1.\u501f\u4e66\u65f6\u81ea\u52a8\u51cf\u5c11\u5e93\u5b58
DELIMITER \/\/
CREATE TRIGGER trg_borrow_before_insert
BEFORE INSERT ON borrow
FOR EACH ROW
BEGIN
DECLARE v_stock INT;
SELECT stock INTO v_stock
FROM book
WHERE bno = NEW.bno;
IF v_stock <= 0 THEN
SIGNAL SQLSTATE '45000'
SET MESSAGE_TEXT = '\u5e93\u5b58\u4e0d\u8db3\uff0c\u4e0d\u80fd\u501f\u4e66';
ELSE
UPDATE book
SET stock = stock - 1
WHERE bno = NEW.bno;
END IF;
END \/\/
DELIMITER ;
\u6d4b\u8bd5\uff1a
SELECT stock FROM book WHERE bno='B003';
INSERT INTO borrow(rno,bno,borrowdate,returndate,actualdate)
VALUES('R2024002','B003','2025-05-01','2025-05-15',NULL);
SELECT stock FROM book WHERE bno='B003';
2.\u8fd8\u4e66\u65f6\u81ea\u52a8\u589e\u52a0\u5e93\u5b58\u5e76\u8ba1\u7b97\u7f5a\u6b3e
DELIMITER \/\/
CREATE TRIGGER trg_return_after_update
AFTER UPDATE ON borrow
FOR EACH ROW
BEGIN
IF OLD.actualdate IS NULL AND NEW.actualdate IS NOT NULL THEN
UPDATE book
SET stock = stock + 1
WHERE bno = NEW.bno;
UPDATE borrow
SET fine =
CASE
WHEN NEW.actualdate > NEW.returndate
THEN DATEDIFF(NEW.actualdate, NEW.returndate) * 1
ELSE 0
END
WHERE borrowid = NEW.borrowid;
END IF;
END \/\/
DELIMITER ;
\u6d4b\u8bd5\uff1a
UPDATE borrow
SET actualdate = '2025-05-18'
WHERE rno='R2024002'
AND bno='B003'
AND borrowdate='2025-05-01';
SELECT * FROM borrow
WHERE rno='R2024002'
AND bno='B003';
SELECT stock FROM book WHERE bno='B003';
3.\u5220\u9664\u8bfb\u8005\u524d\u8bb0\u5f55\u65e5\u5fd7
DELIMITER \/\/
CREATE TRIGGER trg_reader_before_delete
BEFORE DELETE ON reader
FOR EACH ROW
BEGIN
INSERT INTO reader_delete_log(rno,rname,dept)
VALUES(OLD.rno, OLD.rname, OLD.dept);
END \/\/
DELIMITER ;
\u6d4b\u8bd5\uff1a
INSERT INTO reader
VALUES('R2024888','\u65e5\u5fd7\u6d4b\u8bd5','\u7537','\u6d4b\u8bd5\u5b66\u9662','\u65e0');
DELETE FROM reader
WHERE rno='R2024888';
SELECT * FROM reader_delete_log;<\/pre>\n\n\n\n15.\u6570\u636e\u5b89\u5168\u6027<\/h2>\n\n\n\n1.\u521b\u5efa\u7528\u6237\u5e76\u6388\u4e88\u67e5\u8be2\u6743\u9650
CREATE USER 'lib_user1'@'localhost'
IDENTIFIED BY '123456';
GRANT SELECT
ON library_db.book
TO 'lib_user1'@'localhost';
\u67e5\u770b\u6743\u9650\uff1a
SHOW GRANTS FOR 'lib_user1'@'localhost';
2.\u6388\u4e88\u6743\u9650\u5e76\u5141\u8bb8\u8f6c\u6388\u6743
GRANT SELECT, INSERT
ON library_db.reader
TO 'lib_user1'@'localhost'
WITH GRANT OPTION;
\u8bf4\u660e\uff1a
WITH GRANT OPTION \u8868\u793a\u8be5\u7528\u6237\u53ef\u4ee5\u5c06\u81ea\u5df1\u62e5\u6709\u7684\u6743\u9650\u518d\u6388\u4e88\u5176\u4ed6\u7528\u6237\u3002
3.\u56de\u6536\u6743\u9650
REVOKE INSERT
ON library_db.reader
FROM 'lib_user1'@'localhost';
4.\u521b\u5efa\u89d2\u8272\u5e76\u6388\u6743
CREATE ROLE 'reader_role';
GRANT SELECT
ON library_db.*
TO 'reader_role';
CREATE USER 'lib_user2'@'localhost'
IDENTIFIED BY '123456';
GRANT 'reader_role'
TO 'lib_user2'@'localhost';
SET DEFAULT ROLE 'reader_role'
TO 'lib_user2'@'localhost';<\/pre>\n\n\n\n16.\u89c6\u56fe\u4e0e\u6d3e\u751f\u8868<\/h2>\n\n\n\n1.\u5e26\u805a\u5408\u51fd\u6570\u7684\u89c6\u56fe\uff1a\u7edf\u8ba1\u6bcf\u4e2a\u8bfb\u8005\u501f\u9605\u6b21\u6570
CREATE VIEW v_reader_borrow_count AS
SELECT r.rno, r.rname, COUNT(br.borrowid) AS borrow_count
FROM reader r
LEFT JOIN borrow br
ON r.rno = br.rno
GROUP BY r.rno, r.rname;
\u67e5\u8be2\uff1a
SELECT * FROM v_reader_borrow_count;
2.\u6d3e\u751f\u8868\uff1a\u67e5\u8be2\u501f\u9605\u6b21\u6570\u5927\u4e8e1\u7684\u8bfb\u8005
SELECT *
FROM (
SELECT rno, COUNT(*) AS borrow_count
FROM borrow
GROUP BY rno
) AS t
WHERE t.borrow_count > 1;
3.WITH \u5b50\u53e5\u7edf\u8ba1\u6bcf\u4f4d\u8bfb\u8005\u501f\u9605\u6570\u91cf
WITH reader_count AS (
SELECT rno, COUNT(*) AS total
FROM borrow
GROUP BY rno
)
SELECT r.rno, r.rname, rc.total
FROM reader r
LEFT JOIN reader_count rc
ON r.rno = rc.rno;
4.WITH \u5b50\u53e5\uff1a\u67e5\u8be2\u672a\u5f52\u8fd8\u56fe\u4e66
WITH unreturned AS (
SELECT br.borrowid, r.rname, b.bname,
br.borrowdate, br.returndate
FROM borrow br
JOIN reader r ON br.rno = r.rno
JOIN book b ON br.bno = b.bno
WHERE br.actualdate IS NULL
)
SELECT * FROM unreturned;<\/pre>\n\n\n\n17.\u6269\u5c55\u601d\u8003<\/h2>\n\n\n\n\n- \u5982\u4f55\u5904\u7406\u5206\u7c7b\u5b9e\u4f53\u7684\u81ea\u5173\u8054\uff1f<\/li>\n<\/ol>\n\n\n\n
\u5206\u7c7b\u5b9e\u4f53\u5b58\u5728\u201c\u4e0a\u7ea7\u5206\u7c7b\u201d\u548c\u201c\u4e0b\u7ea7\u5206\u7c7b\u201d\u7684\u5173\u7cfb\uff0c\u56e0\u6b64\u53ef\u4ee5\u5728 category \u8868\u4e2d\u8bbe\u7f6e parentid \u5b57\u6bb5\u3002
category(
cid,
cname,
parentid
)
\u5176\u4e2d cid \u662f\u5206\u7c7b\u7f16\u53f7\uff0cparentid \u662f\u4e0a\u7ea7\u5206\u7c7b\u7f16\u53f7\uff0c\u540c\u65f6 parentid \u4e5f\u662f\u6307\u5411 category.cid \u7684\u5916\u952e\u3002
\u5982\u679c\u67d0\u5206\u7c7b\u6ca1\u6709\u4e0a\u7ea7\u5206\u7c7b\uff0c\u5219 parentid \u53ef\u4ee5\u4e3a\u7a7a\u3002
\u8fd9\u79cd\u8bbe\u8ba1\u53ef\u4ee5\u8868\u793a\u6811\u5f62\u7ed3\u6784\uff0c\u4f8b\u5982\uff1a
\u56fe\u4e66
\u251c\u2500\u2500 \u8ba1\u7b97\u673a
\u2502 \u251c\u2500\u2500 \u6570\u636e\u5e93
\u2502 \u2514\u2500\u2500 \u7f51\u7edc\u6280\u672f
\u2514\u2500\u2500 \u6587\u5b66
\u2514\u2500\u2500 \u79d1\u5e7b\u5c0f\u8bf4<\/pre>\n\n\n\n
\n\n\n\n2. \u501f\u9605\u5173\u7cfb\u662f\u5426\u53ef\u80fd\u5b58\u5728\u6570\u636e\u5197\u4f59\uff1f<\/h2>\n\n\n\n\u501f\u9605\u8868\u5982\u679c\u53ea\u4fdd\u5b58 rno\u3001bno\u3001borrowdate\u3001returndate\u3001actualdate \u7b49\u4fe1\u606f\uff0c\u5219\u5197\u4f59\u8f83\u5c11\u3002
\u4f46\u662f\u5982\u679c\u5728 borrow \u8868\u4e2d\u540c\u65f6\u4fdd\u5b58\u8bfb\u8005\u59d3\u540d rname\u3001\u56fe\u4e66\u540d\u79f0 bname\u3001\u51fa\u7248\u793e press \u7b49\u4fe1\u606f\uff0c\u5c31\u4f1a\u4ea7\u751f\u6570\u636e\u5197\u4f59\u3002
\u4f8b\u5982\uff1a
borrow(borrowid, rno, rname, bno, bname, borrowdate)
\u5176\u4e2d rname \u4f9d\u8d56 rno\uff0cbname \u4f9d\u8d56 bno\uff0c\u800c\u4e0d\u662f\u76f4\u63a5\u4f9d\u8d56 borrowid\uff0c\u4f1a\u4ea7\u751f\u4f20\u9012\u4f9d\u8d56\u3002
\u89c4\u8303\u5316\u65b9\u6848\uff1a
\u5c06\u8bfb\u8005\u4fe1\u606f\u4fdd\u5b58\u5728 reader \u8868\uff1b
\u5c06\u56fe\u4e66\u4fe1\u606f\u4fdd\u5b58\u5728 book \u8868\uff1b
borrow \u8868\u53ea\u4fdd\u5b58\u8bfb\u8005\u8bc1\u53f7\u548c\u56fe\u4e66\u7f16\u53f7\u4f5c\u4e3a\u5916\u952e\u3002<\/pre>\n\n\n\n
\n\n\n\n3. \u5982\u4f55\u9632\u6b62\u5e93\u5b58\u4e3a\u8d1f\u6570\uff1f<\/h2>\n\n\n\n\u53ef\u4ee5\u4ece\u4e24\u4e2a\u65b9\u9762\u9632\u6b62\u5e93\u5b58\u4e3a\u8d1f\u6570\uff1a
\u7b2c\u4e00\uff0c\u5728 book \u8868\u4e2d\u8bbe\u7f6e CHECK(stock >= 0) \u7ea6\u675f\uff0c\u4fdd\u8bc1\u5e93\u5b58\u4e0d\u80fd\u5c0f\u4e8e0\u3002
\u7b2c\u4e8c\uff0c\u5728\u501f\u4e66\u89e6\u53d1\u5668\u4e2d\u5224\u65ad\u5e93\u5b58\u6570\u91cf\u3002
\u5f53\u63d2\u5165 borrow \u501f\u9605\u8bb0\u5f55\u65f6\uff0c\u5148\u67e5\u8be2\u56fe\u4e66\u5e93\u5b58\u3002
\u5982\u679c\u5e93\u5b58\u5c0f\u4e8e\u7b49\u4e8e0\uff0c\u5219\u4f7f\u7528 SIGNAL \u629b\u51fa\u9519\u8bef\uff0c\u963b\u6b62\u501f\u4e66\u64cd\u4f5c\uff1b
\u5982\u679c\u5e93\u5b58\u5927\u4e8e0\uff0c\u5219\u5141\u8bb8\u501f\u9605\uff0c\u5e76\u81ea\u52a8\u5c06\u5e93\u5b58\u51cf1\u3002
\u8fd9\u6837\u53ef\u4ee5\u4fdd\u8bc1\u501f\u4e66\u65f6\u4e0d\u4f1a\u51fa\u73b0\u5e93\u5b58\u4e3a\u8d1f\u6570\u7684\u60c5\u51b5\u3002<\/pre>\n\n\n\n
\n\n\n\n4. \u9884\u7ea6\u56fe\u4e66\u529f\u80fd\u9700\u8981\u589e\u52a0\u54ea\u4e9b\u5b9e\u4f53\u548c\u5173\u7cfb\uff1f<\/h2>\n\n\n\n\u5982\u679c\u7cfb\u7edf\u652f\u6301\u9884\u7ea6\u56fe\u4e66\u529f\u80fd\uff0c\u53ef\u4ee5\u589e\u52a0 reservation \u9884\u7ea6\u8868\u3002
reservation(
reserveid,
rno,
bno,
reservedate,
status
)
\u5176\u4e2d\uff1a
reserveid \u8868\u793a\u9884\u7ea6\u7f16\u53f7\uff1b
rno \u662f\u8bfb\u8005\u8bc1\u53f7\uff0c\u5916\u952e\u5f15\u7528 reader.rno\uff1b
bno \u662f\u56fe\u4e66\u7f16\u53f7\uff0c\u5916\u952e\u5f15\u7528 book.bno\uff1b
reservedate \u8868\u793a\u9884\u7ea6\u65e5\u671f\uff1b
status \u8868\u793a\u9884\u7ea6\u72b6\u6001\uff0c\u5982\u201c\u9884\u7ea6\u4e2d\u201d\u201c\u5df2\u53d6\u6d88\u201d\u201c\u5df2\u5b8c\u6210\u201d\u3002
\u65b0\u589e\u5173\u7cfb\uff1a
\u4e00\u4e2a\u8bfb\u8005\u53ef\u4ee5\u9884\u7ea6\u591a\u672c\u56fe\u4e66\uff1b
\u4e00\u672c\u56fe\u4e66\u53ef\u4ee5\u88ab\u591a\u4e2a\u8bfb\u8005\u9884\u7ea6\uff1b
\u8bfb\u8005\u548c\u56fe\u4e66\u4e4b\u95f4\u901a\u8fc7 reservation \u8868\u5f62\u6210 m:n \u8054\u7cfb\u3002<\/pre>\n\n\n\n
\n\n\n\n5. \u4e3a\u4ec0\u4e48\u9075\u5faa\u6700\u5c0f\u6743\u9650\u539f\u5219\uff1f<\/h2>\n\n\n\n\u6700\u5c0f\u6743\u9650\u539f\u5219\u662f\u6307\u53ea\u7ed9\u7528\u6237\u5b8c\u6210\u5de5\u4f5c\u6240\u5fc5\u9700\u7684\u6743\u9650\uff0c\u4e0d\u6388\u4e88\u591a\u4f59\u6743\u9650\u3002
\u5728\u672c\u5b9e\u9a8c\u4e2d\uff0c\u5982\u679c\u67d0\u7528\u6237\u53ea\u8d1f\u8d23\u67e5\u8be2\u56fe\u4e66\u4fe1\u606f\uff0c\u5219\u53ea\u6388\u4e88 SELECT \u6743\u9650\u5373\u53ef\uff0c\u4e0d\u5e94\u8be5\u6388\u4e88 INSERT\u3001UPDATE\u3001DELETE \u7b49\u6743\u9650\u3002
\u4f8b\u5982\uff1a
GRANT SELECT ON library_db.book TO 'lib_user1'@'localhost';
\u8fd9\u6837\u53ef\u4ee5\u9632\u6b62\u7528\u6237\u8bef\u5220\u3001\u8bef\u6539\u6570\u636e\uff0c\u63d0\u9ad8\u6570\u636e\u5e93\u5b89\u5168\u6027\u3002
\u5982\u679c\u540e\u7eed\u4e0d\u518d\u9700\u8981\u67d0\u9879\u6743\u9650\uff0c\u8fd8\u53ef\u4ee5\u4f7f\u7528 REVOKE \u56de\u6536\u6743\u9650\u3002<\/pre>\n\n\n\n
\n\n\n\n6. \u5e76\u53d1\u501f\u9605\u5e93\u5b58\u4ec5\u52691\u672c\u7684\u56fe\u4e66\u4f1a\u4ea7\u751f\u4ec0\u4e48\u95ee\u9898\uff1f\u5982\u4f55\u89e3\u51b3\uff1f<\/h2>\n\n\n\n\u5f53\u591a\u7528\u6237\u540c\u65f6\u501f\u9605\u540c\u4e00\u672c\u5e93\u5b58\u4ec5\u52691\u672c\u7684\u56fe\u4e66\u65f6\uff0c\u53ef\u80fd\u51fa\u73b0\u8d85\u5356\u95ee\u9898\u3002
\u4f8b\u5982\u4e24\u4e2a\u7528\u6237\u540c\u65f6\u8bfb\u53d6\u5e93\u5b58 stock=1\uff0c\u90fd\u8ba4\u4e3a\u53ef\u4ee5\u501f\u9605\uff0c\u7136\u540e\u540c\u65f6\u63d2\u5165\u501f\u9605\u8bb0\u5f55\u5e76\u6267\u884c\u5e93\u5b58\u51cf1\uff0c\u6700\u7ec8\u53ef\u80fd\u5bfc\u81f4\u5e93\u5b58\u5f02\u5e38\u6216\u51fa\u73b0\u8d85\u989d\u501f\u9605\u3002
\u89e3\u51b3\u65b9\u6cd5\uff1a
1. \u4f7f\u7528\u4e8b\u52a1\u4fdd\u8bc1\u501f\u4e66\u64cd\u4f5c\u7684\u539f\u5b50\u6027\uff1b
2. \u4f7f\u7528 SELECT ... FOR UPDATE \u5bf9\u56fe\u4e66\u5e93\u5b58\u8bb0\u5f55\u52a0\u884c\u7ea7\u9501\uff1b
3. \u5728\u89e6\u53d1\u5668\u4e2d\u5224\u65ad\u5e93\u5b58\u662f\u5426\u5927\u4e8e0\uff1b
4. \u7ed9 stock \u5b57\u6bb5\u8bbe\u7f6e CHECK(stock >= 0) \u7ea6\u675f\u3002
\u793a\u4f8b\uff1a
START TRANSACTION;
SELECT stock
FROM book
WHERE bno='B001'
FOR UPDATE;
UPDATE book
SET stock = stock - 1
WHERE bno='B001'
AND stock > 0;
INSERT INTO borrow(rno,bno,borrowdate,returndate)
VALUES('R2024001','B001','2025-05-01','2025-05-15');
COMMIT;
\u8fd9\u6837\u53ef\u4ee5\u907f\u514d\u591a\u4e2a\u7528\u6237\u540c\u65f6\u4fee\u6539\u5e93\u5b58\u5bfc\u81f4\u6570\u636e\u4e0d\u4e00\u81f4\u3002<\/pre>\n\n\n\n
\n\n\n\n\u5b9e\u9a8c\u603b\u7ed3<\/h1>\n\n\n\n \u901a\u8fc7\u672c\u6b21\u56fe\u4e66\u501f\u9605\u7ba1\u7406\u7cfb\u7edf\u7efc\u5408\u5b9e\u9a8c\uff0c\u6211\u7cfb\u7edf\u5730\u5b8c\u6210\u4e86\u6570\u636e\u5e93\u8bbe\u8ba1\u4e0e\u5b9e\u73b0\u7684\u5168\u8fc7\u7a0b\u3002\u5b9e\u9a8c\u4ece\u9700\u6c42\u5206\u6790\u5f00\u59cb\uff0c\u9010\u6b65\u5b8c\u6210 E-R \u56fe\u8bbe\u8ba1\u3001\u5173\u7cfb\u6a21\u5f0f\u8f6c\u6362\u3001\u7269\u7406\u8868\u7ed3\u6784\u8bbe\u8ba1\u3001\u6570\u636e\u63d2\u5165\u3001\u67e5\u8be2\u64cd\u4f5c\u3001\u89c6\u56fe\u3001\u7d22\u5f15\u3001\u5b8c\u6574\u6027\u7ea6\u675f\u3001\u89e6\u53d1\u5668\u548c\u6743\u9650\u7ba1\u7406\u7b49\u5185\u5bb9\uff0c\u4f7f\u6211\u5bf9\u6570\u636e\u5e93\u5e94\u7528\u7cfb\u7edf\u7684\u8bbe\u8ba1\u6d41\u7a0b\u6709\u4e86\u66f4\u52a0\u5b8c\u6574\u7684\u8ba4\u8bc6\u3002
\u200b
\u5728\u5b9e\u9a8c\u8fc7\u7a0b\u4e2d\uff0c\u6211\u9996\u5148\u6839\u636e\u56fe\u4e66\u9986\u4e1a\u52a1\u9700\u6c42\u5206\u6790\u51fa\u56fe\u4e66\u3001\u8bfb\u8005\u3001\u501f\u9605\u3001\u51fa\u7248\u793e\u3001\u5206\u7c7b\u7b49\u5b9e\u4f53\uff0c\u5e76\u660e\u786e\u4e86\u5b83\u4eec\u4e4b\u95f4\u7684\u8054\u7cfb\u7c7b\u578b\u3002\u4f8b\u5982\uff0c\u51fa\u7248\u793e\u4e0e\u56fe\u4e66\u4e4b\u95f4\u662f\u4e00\u5bf9\u591a\u5173\u7cfb\uff0c\u5206\u7c7b\u4e0e\u56fe\u4e66\u4e4b\u95f4\u662f\u4e00\u5bf9\u591a\u5173\u7cfb\uff0c\u8bfb\u8005\u4e0e\u56fe\u4e66\u4e4b\u95f4\u901a\u8fc7\u501f\u9605\u8868\u5f62\u6210\u591a\u5bf9\u591a\u5173\u7cfb\u3002\u901a\u8fc7 E-R \u56fe\u8bbe\u8ba1\uff0c\u6211\u8fdb\u4e00\u6b65\u7406\u89e3\u4e86\u6982\u5ff5\u7ed3\u6784\u8bbe\u8ba1\u5728\u6570\u636e\u5e93\u5f00\u53d1\u4e2d\u7684\u91cd\u8981\u4f5c\u7528\u3002
\u200b
\u5728\u903b\u8f91\u7ed3\u6784\u8bbe\u8ba1\u9636\u6bb5\uff0c\u6211\u5c06 E-R \u56fe\u8f6c\u6362\u4e3a\u5173\u7cfb\u6a21\u5f0f\uff0c\u5e76\u5206\u6790\u5404\u8868\u662f\u5426\u6ee1\u8db3\u7b2c\u4e09\u8303\u5f0f\u3002\u901a\u8fc7\u89c4\u8303\u5316\u8bbe\u8ba1\uff0c\u907f\u514d\u4e86\u5728\u501f\u9605\u8868\u4e2d\u91cd\u590d\u4fdd\u5b58\u8bfb\u8005\u59d3\u540d\u3001\u56fe\u4e66\u540d\u79f0\u7b49\u4fe1\u606f\uff0c\u51cf\u5c11\u4e86\u6570\u636e\u5197\u4f59\uff0c\u63d0\u9ad8\u4e86\u6570\u636e\u4e00\u81f4\u6027\u3002\u5728\u7269\u7406\u8bbe\u8ba1\u9636\u6bb5\uff0c\u6211\u4f7f\u7528 SQL \u521b\u5efa\u6570\u636e\u5e93\u548c\u6570\u636e\u8868\uff0c\u8bbe\u7f6e\u4e86\u4e3b\u952e\u3001\u5916\u952e\u3001\u975e\u7a7a\u3001\u9ed8\u8ba4\u503c\u548c CHECK \u7ea6\u675f\uff0c\u5bf9\u5b9e\u4f53\u5b8c\u6574\u6027\u3001\u53c2\u7167\u5b8c\u6574\u6027\u548c\u7528\u6237\u5b9a\u4e49\u5b8c\u6574\u6027\u6709\u4e86\u66f4\u6df1\u523b\u7684\u7406\u89e3\u3002
\u200b
\u5728\u6570\u636e\u64cd\u4f5c\u90e8\u5206\uff0c\u6211\u7ec3\u4e60\u4e86 INSERT\u3001UPDATE\u3001DELETE \u548c SELECT \u8bed\u53e5\uff0c\u5e76\u5b8c\u6210\u4e86\u57fa\u7840\u67e5\u8be2\u3001\u805a\u5408\u67e5\u8be2\u3001\u591a\u8868\u8fde\u63a5\u67e5\u8be2\u3001\u5d4c\u5957\u67e5\u8be2\u548c\u96c6\u5408\u67e5\u8be2\u7b49\u5185\u5bb9\u3002\u901a\u8fc7\u8fd9\u4e9b\u7ec3\u4e60\uff0c\u6211\u638c\u63e1\u4e86 SQL \u67e5\u8be2\u8bed\u53e5\u7684\u5e38\u89c1\u5199\u6cd5\uff0c\u5c24\u5176\u662f\u591a\u8868\u8fde\u63a5\u548c\u5d4c\u5957\u67e5\u8be2\u7684\u4f7f\u7528\u65b9\u6cd5\u3002\u5b9e\u9a8c\u4e2d\u8fd8\u521b\u5efa\u4e86\u89c6\u56fe\u548c\u7d22\u5f15\uff0c\u7406\u89e3\u4e86\u89c6\u56fe\u53ef\u4ee5\u7b80\u5316\u590d\u6742\u67e5\u8be2\uff0c\u7d22\u5f15\u53ef\u4ee5\u63d0\u9ad8\u67e5\u8be2\u6548\u7387\uff0c\u4f46\u4e5f\u4f1a\u589e\u52a0\u7ef4\u62a4\u6210\u672c\u3002
\u200b
\u5728\u89e6\u53d1\u5668\u90e8\u5206\uff0c\u6211\u5b9e\u73b0\u4e86\u501f\u4e66\u81ea\u52a8\u51cf\u5c11\u5e93\u5b58\u3001\u8fd8\u4e66\u81ea\u52a8\u589e\u52a0\u5e93\u5b58\u5e76\u8ba1\u7b97\u7f5a\u6b3e\u3001\u5220\u9664\u8bfb\u8005\u524d\u8bb0\u5f55\u65e5\u5fd7\u7b49\u529f\u80fd\u3002\u901a\u8fc7\u89e6\u53d1\u5668\u5b9e\u9a8c\uff0c\u6211\u8ba4\u8bc6\u5230\u6570\u636e\u5e93\u4e0d\u4ec5\u53ef\u4ee5\u5b58\u50a8\u6570\u636e\uff0c\u8fd8\u53ef\u4ee5\u5728\u7279\u5b9a\u64cd\u4f5c\u53d1\u751f\u65f6\u81ea\u52a8\u6267\u884c\u4e00\u4e9b\u4e1a\u52a1\u903b\u8f91\u3002\u5b9e\u9a8c\u8fc7\u7a0b\u4e2d\u4e5f\u9047\u5230\u4e86\u4e00\u4e9b\u95ee\u9898\uff0c\u4f8b\u5982\u5916\u952e\u7ea6\u675f\u5bfc\u81f4\u6570\u636e\u65e0\u6cd5\u5220\u9664\u3001CHECK \u7ea6\u675f\u63d2\u5165\u5931\u8d25\u3001\u89e6\u53d1\u5668\u8bed\u6cd5\u9519\u8bef\u7b49\u3002\u901a\u8fc7\u67e5\u770b\u9519\u8bef\u4fe1\u606f\u3001\u4fee\u6539 SQL \u8bed\u53e5\u548c\u53cd\u590d\u6d4b\u8bd5\uff0c\u6700\u7ec8\u89e3\u51b3\u4e86\u8fd9\u4e9b\u95ee\u9898\u3002
\u200b
\u901a\u8fc7\u672c\u6b21\u5b9e\u9a8c\uff0c\u6211\u4e0d\u4ec5\u5de9\u56fa\u4e86\u6570\u636e\u5e93\u7406\u8bba\u77e5\u8bc6\uff0c\u4e5f\u63d0\u9ad8\u4e86 SQL \u7f16\u5199\u80fd\u529b\u548c\u6570\u636e\u5e93\u8c03\u8bd5\u80fd\u529b\u3002\u4eca\u540e\u5728\u8bbe\u8ba1\u6570\u636e\u5e93\u7cfb\u7edf<\/pre>\n","protected":false},"excerpt":{"rendered":"\u6570\u636e\u5e93\u7efc\u5408\u5b9e\u9a8c 1.\u9700\u6c42\u5206\u6790 \u67d0\u5927\u578b\u56fe\u4e66\u9986\u9700\u8981\u5f00\u53d1\u4e00\u5957\u6570\u5b57\u5316\u501f\u9605\u7ba1\u7406\u7cfb\u7edf\uff0c\u4e3b\u8981\u4e1a\u52a1\u9700\u6c42\u5982\u4e0b\uff1a \u56fe\u4e66\u4fe1\u606f\uff1a\u8bb0\u5f55\u56fe […]<\/p>\n","protected":false},"author":1,"featured_media":448,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[9],"tags":[],"class_list":["post-446","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-wenzhang"],"_links":{"self":[{"href":"https:\/\/fg2025.cn\/index.php\/wp-json\/wp\/v2\/posts\/446","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/fg2025.cn\/index.php\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/fg2025.cn\/index.php\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/fg2025.cn\/index.php\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/fg2025.cn\/index.php\/wp-json\/wp\/v2\/comments?post=446"}],"version-history":[{"count":0,"href":"https:\/\/fg2025.cn\/index.php\/wp-json\/wp\/v2\/posts\/446\/revisions"}],"wp:attachment":[{"href":"https:\/\/fg2025.cn\/index.php\/wp-json\/wp\/v2\/media?parent=446"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/fg2025.cn\/index.php\/wp-json\/wp\/v2\/categories?post=446"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/fg2025.cn\/index.php\/wp-json\/wp\/v2\/tags?post=446"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}
INSERT INTO book(bno,bname,author,press,pubyear,stock)
VALUES(NULL,'\u6d4b\u8bd5\u4e66','\u6d4b\u8bd5\u4f5c\u8005','\u6d4b\u8bd5\u51fa\u7248\u793e',2020,1);
\u8bf4\u660e\uff1a
bno \u662f book \u8868\u4e3b\u952e\uff0c\u4e3b\u952e\u4e0d\u80fd\u4e3a\u7a7a\uff0c\u56e0\u6b64\u63d2\u5165\u5931\u8d25\u3002
2.\u53c2\u7167\u5b8c\u6574\u6027\u9a8c\u8bc1\uff1a\u63d2\u5165\u4e0d\u5b58\u5728\u7684\u56fe\u4e66\u7f16\u53f7
INSERT INTO borrow(rno,bno,borrowdate,returndate,actualdate)
VALUES('R2024001','B999','2025-05-01','2025-05-15',NULL);
\u8bf4\u660e\uff1a
B999 \u5728 book \u8868\u4e2d\u4e0d\u5b58\u5728\uff0cborrow.bno \u662f\u5916\u952e\uff0c\u56e0\u6b64\u8fdd\u53cd\u53c2\u7167\u5b8c\u6574\u6027\u3002
3.\u7528\u6237\u5b9a\u4e49\u5b8c\u6574\u6027\u9a8c\u8bc1\uff1a\u5e93\u5b58\u4e0d\u80fd\u5c0f\u4e8e0
UPDATE book
SET stock = -1
WHERE bno = 'B001';
\u8bf4\u660e\uff1a
stock \u5b57\u6bb5\u8bbe\u7f6e\u4e86 CHECK(stock>=0)\uff0c\u5e93\u5b58\u4e0d\u80fd\u4e3a\u8d1f\u6570\u3002
4.\u7528\u6237\u5b9a\u4e49\u5b8c\u6574\u6027\u9a8c\u8bc1\uff1a\u5e93\u5b58\u4e0d\u80fd\u5c0f\u4e8e0
UPDATE book
SET stock = -1
WHERE bno = 'B001';
\u8bf4\u660e\uff1a
stock \u5b57\u6bb5\u8bbe\u7f6e\u4e86 CHECK(stock>=0)\uff0c\u5e93\u5b58\u4e0d\u80fd\u4e3a\u8d1f\u6570\u3002
5.ON UPDATE CASCADE \u6d4b\u8bd5
UPDATE reader
SET rno = 'R2024999'
WHERE rno = 'R2024003';
SELECT * FROM borrow
WHERE rno = 'R2024999';
\u8bf4\u660e\uff1a
reader.rno \u66f4\u65b0\u540e\uff0cborrow \u8868\u4e2d\u5bf9\u5e94\u7684\u5916\u952e rno \u4f1a\u81ea\u52a8\u540c\u6b65\u66f4\u65b0\u3002<\/pre>\n\n\n\n
14.\u89e6\u53d1\u5668<\/h2>\n\n\n\n\u51c6\u5907\uff1a\u5220\u9664\u65e7\u89e6\u53d1\u5668
DROP TRIGGER IF EXISTS trg_borrow_before_insert;
DROP TRIGGER IF EXISTS trg_return_after_update;
DROP TRIGGER IF EXISTS trg_reader_before_delete;
\u521b\u5efa\u5220\u9664\u8bfb\u8005\u65e5\u5fd7\u8868
CREATE TABLE reader_delete_log(
logid INT AUTO_INCREMENT PRIMARY KEY,
rno CHAR(12),
rname VARCHAR(20),
dept VARCHAR(40),
delete_time DATETIME DEFAULT CURRENT_TIMESTAMP
);
1.\u501f\u4e66\u65f6\u81ea\u52a8\u51cf\u5c11\u5e93\u5b58
DELIMITER \/\/
CREATE TRIGGER trg_borrow_before_insert
BEFORE INSERT ON borrow
FOR EACH ROW
BEGIN
DECLARE v_stock INT;
SELECT stock INTO v_stock
FROM book
WHERE bno = NEW.bno;
IF v_stock <= 0 THEN
SIGNAL SQLSTATE '45000'
SET MESSAGE_TEXT = '\u5e93\u5b58\u4e0d\u8db3\uff0c\u4e0d\u80fd\u501f\u4e66';
ELSE
UPDATE book
SET stock = stock - 1
WHERE bno = NEW.bno;
END IF;
END \/\/
DELIMITER ;
\u6d4b\u8bd5\uff1a
SELECT stock FROM book WHERE bno='B003';
INSERT INTO borrow(rno,bno,borrowdate,returndate,actualdate)
VALUES('R2024002','B003','2025-05-01','2025-05-15',NULL);
SELECT stock FROM book WHERE bno='B003';
2.\u8fd8\u4e66\u65f6\u81ea\u52a8\u589e\u52a0\u5e93\u5b58\u5e76\u8ba1\u7b97\u7f5a\u6b3e
DELIMITER \/\/
CREATE TRIGGER trg_return_after_update
AFTER UPDATE ON borrow
FOR EACH ROW
BEGIN
IF OLD.actualdate IS NULL AND NEW.actualdate IS NOT NULL THEN
UPDATE book
SET stock = stock + 1
WHERE bno = NEW.bno;
UPDATE borrow
SET fine =
CASE
WHEN NEW.actualdate > NEW.returndate
THEN DATEDIFF(NEW.actualdate, NEW.returndate) * 1
ELSE 0
END
WHERE borrowid = NEW.borrowid;
END IF;
END \/\/
DELIMITER ;
\u6d4b\u8bd5\uff1a
UPDATE borrow
SET actualdate = '2025-05-18'
WHERE rno='R2024002'
AND bno='B003'
AND borrowdate='2025-05-01';
SELECT * FROM borrow
WHERE rno='R2024002'
AND bno='B003';
SELECT stock FROM book WHERE bno='B003';
3.\u5220\u9664\u8bfb\u8005\u524d\u8bb0\u5f55\u65e5\u5fd7
DELIMITER \/\/
CREATE TRIGGER trg_reader_before_delete
BEFORE DELETE ON reader
FOR EACH ROW
BEGIN
INSERT INTO reader_delete_log(rno,rname,dept)
VALUES(OLD.rno, OLD.rname, OLD.dept);
END \/\/
DELIMITER ;
\u6d4b\u8bd5\uff1a
INSERT INTO reader
VALUES('R2024888','\u65e5\u5fd7\u6d4b\u8bd5','\u7537','\u6d4b\u8bd5\u5b66\u9662','\u65e0');
DELETE FROM reader
WHERE rno='R2024888';
SELECT * FROM reader_delete_log;<\/pre>\n\n\n\n15.\u6570\u636e\u5b89\u5168\u6027<\/h2>\n\n\n\n1.\u521b\u5efa\u7528\u6237\u5e76\u6388\u4e88\u67e5\u8be2\u6743\u9650
CREATE USER 'lib_user1'@'localhost'
IDENTIFIED BY '123456';
GRANT SELECT
ON library_db.book
TO 'lib_user1'@'localhost';
\u67e5\u770b\u6743\u9650\uff1a
SHOW GRANTS FOR 'lib_user1'@'localhost';
2.\u6388\u4e88\u6743\u9650\u5e76\u5141\u8bb8\u8f6c\u6388\u6743
GRANT SELECT, INSERT
ON library_db.reader
TO 'lib_user1'@'localhost'
WITH GRANT OPTION;
\u8bf4\u660e\uff1a
WITH GRANT OPTION \u8868\u793a\u8be5\u7528\u6237\u53ef\u4ee5\u5c06\u81ea\u5df1\u62e5\u6709\u7684\u6743\u9650\u518d\u6388\u4e88\u5176\u4ed6\u7528\u6237\u3002
3.\u56de\u6536\u6743\u9650
REVOKE INSERT
ON library_db.reader
FROM 'lib_user1'@'localhost';
4.\u521b\u5efa\u89d2\u8272\u5e76\u6388\u6743
CREATE ROLE 'reader_role';
GRANT SELECT
ON library_db.*
TO 'reader_role';
CREATE USER 'lib_user2'@'localhost'
IDENTIFIED BY '123456';
GRANT 'reader_role'
TO 'lib_user2'@'localhost';
SET DEFAULT ROLE 'reader_role'
TO 'lib_user2'@'localhost';<\/pre>\n\n\n\n16.\u89c6\u56fe\u4e0e\u6d3e\u751f\u8868<\/h2>\n\n\n\n1.\u5e26\u805a\u5408\u51fd\u6570\u7684\u89c6\u56fe\uff1a\u7edf\u8ba1\u6bcf\u4e2a\u8bfb\u8005\u501f\u9605\u6b21\u6570
CREATE VIEW v_reader_borrow_count AS
SELECT r.rno, r.rname, COUNT(br.borrowid) AS borrow_count
FROM reader r
LEFT JOIN borrow br
ON r.rno = br.rno
GROUP BY r.rno, r.rname;
\u67e5\u8be2\uff1a
SELECT * FROM v_reader_borrow_count;
2.\u6d3e\u751f\u8868\uff1a\u67e5\u8be2\u501f\u9605\u6b21\u6570\u5927\u4e8e1\u7684\u8bfb\u8005
SELECT *
FROM (
SELECT rno, COUNT(*) AS borrow_count
FROM borrow
GROUP BY rno
) AS t
WHERE t.borrow_count > 1;
3.WITH \u5b50\u53e5\u7edf\u8ba1\u6bcf\u4f4d\u8bfb\u8005\u501f\u9605\u6570\u91cf
WITH reader_count AS (
SELECT rno, COUNT(*) AS total
FROM borrow
GROUP BY rno
)
SELECT r.rno, r.rname, rc.total
FROM reader r
LEFT JOIN reader_count rc
ON r.rno = rc.rno;
4.WITH \u5b50\u53e5\uff1a\u67e5\u8be2\u672a\u5f52\u8fd8\u56fe\u4e66
WITH unreturned AS (
SELECT br.borrowid, r.rname, b.bname,
br.borrowdate, br.returndate
FROM borrow br
JOIN reader r ON br.rno = r.rno
JOIN book b ON br.bno = b.bno
WHERE br.actualdate IS NULL
)
SELECT * FROM unreturned;<\/pre>\n\n\n\n17.\u6269\u5c55\u601d\u8003<\/h2>\n\n\n\n\n- \u5982\u4f55\u5904\u7406\u5206\u7c7b\u5b9e\u4f53\u7684\u81ea\u5173\u8054\uff1f<\/li>\n<\/ol>\n\n\n\n
\u5206\u7c7b\u5b9e\u4f53\u5b58\u5728\u201c\u4e0a\u7ea7\u5206\u7c7b\u201d\u548c\u201c\u4e0b\u7ea7\u5206\u7c7b\u201d\u7684\u5173\u7cfb\uff0c\u56e0\u6b64\u53ef\u4ee5\u5728 category \u8868\u4e2d\u8bbe\u7f6e parentid \u5b57\u6bb5\u3002
category(
cid,
cname,
parentid
)
\u5176\u4e2d cid \u662f\u5206\u7c7b\u7f16\u53f7\uff0cparentid \u662f\u4e0a\u7ea7\u5206\u7c7b\u7f16\u53f7\uff0c\u540c\u65f6 parentid \u4e5f\u662f\u6307\u5411 category.cid \u7684\u5916\u952e\u3002
\u5982\u679c\u67d0\u5206\u7c7b\u6ca1\u6709\u4e0a\u7ea7\u5206\u7c7b\uff0c\u5219 parentid \u53ef\u4ee5\u4e3a\u7a7a\u3002
\u8fd9\u79cd\u8bbe\u8ba1\u53ef\u4ee5\u8868\u793a\u6811\u5f62\u7ed3\u6784\uff0c\u4f8b\u5982\uff1a
\u56fe\u4e66
\u251c\u2500\u2500 \u8ba1\u7b97\u673a
\u2502 \u251c\u2500\u2500 \u6570\u636e\u5e93
\u2502 \u2514\u2500\u2500 \u7f51\u7edc\u6280\u672f
\u2514\u2500\u2500 \u6587\u5b66
\u2514\u2500\u2500 \u79d1\u5e7b\u5c0f\u8bf4<\/pre>\n\n\n\n
\n\n\n\n2. \u501f\u9605\u5173\u7cfb\u662f\u5426\u53ef\u80fd\u5b58\u5728\u6570\u636e\u5197\u4f59\uff1f<\/h2>\n\n\n\n\u501f\u9605\u8868\u5982\u679c\u53ea\u4fdd\u5b58 rno\u3001bno\u3001borrowdate\u3001returndate\u3001actualdate \u7b49\u4fe1\u606f\uff0c\u5219\u5197\u4f59\u8f83\u5c11\u3002
\u4f46\u662f\u5982\u679c\u5728 borrow \u8868\u4e2d\u540c\u65f6\u4fdd\u5b58\u8bfb\u8005\u59d3\u540d rname\u3001\u56fe\u4e66\u540d\u79f0 bname\u3001\u51fa\u7248\u793e press \u7b49\u4fe1\u606f\uff0c\u5c31\u4f1a\u4ea7\u751f\u6570\u636e\u5197\u4f59\u3002
\u4f8b\u5982\uff1a
borrow(borrowid, rno, rname, bno, bname, borrowdate)
\u5176\u4e2d rname \u4f9d\u8d56 rno\uff0cbname \u4f9d\u8d56 bno\uff0c\u800c\u4e0d\u662f\u76f4\u63a5\u4f9d\u8d56 borrowid\uff0c\u4f1a\u4ea7\u751f\u4f20\u9012\u4f9d\u8d56\u3002
\u89c4\u8303\u5316\u65b9\u6848\uff1a
\u5c06\u8bfb\u8005\u4fe1\u606f\u4fdd\u5b58\u5728 reader \u8868\uff1b
\u5c06\u56fe\u4e66\u4fe1\u606f\u4fdd\u5b58\u5728 book \u8868\uff1b
borrow \u8868\u53ea\u4fdd\u5b58\u8bfb\u8005\u8bc1\u53f7\u548c\u56fe\u4e66\u7f16\u53f7\u4f5c\u4e3a\u5916\u952e\u3002<\/pre>\n\n\n\n
\n\n\n\n3. \u5982\u4f55\u9632\u6b62\u5e93\u5b58\u4e3a\u8d1f\u6570\uff1f<\/h2>\n\n\n\n\u53ef\u4ee5\u4ece\u4e24\u4e2a\u65b9\u9762\u9632\u6b62\u5e93\u5b58\u4e3a\u8d1f\u6570\uff1a
\u7b2c\u4e00\uff0c\u5728 book \u8868\u4e2d\u8bbe\u7f6e CHECK(stock >= 0) \u7ea6\u675f\uff0c\u4fdd\u8bc1\u5e93\u5b58\u4e0d\u80fd\u5c0f\u4e8e0\u3002
\u7b2c\u4e8c\uff0c\u5728\u501f\u4e66\u89e6\u53d1\u5668\u4e2d\u5224\u65ad\u5e93\u5b58\u6570\u91cf\u3002
\u5f53\u63d2\u5165 borrow \u501f\u9605\u8bb0\u5f55\u65f6\uff0c\u5148\u67e5\u8be2\u56fe\u4e66\u5e93\u5b58\u3002
\u5982\u679c\u5e93\u5b58\u5c0f\u4e8e\u7b49\u4e8e0\uff0c\u5219\u4f7f\u7528 SIGNAL \u629b\u51fa\u9519\u8bef\uff0c\u963b\u6b62\u501f\u4e66\u64cd\u4f5c\uff1b
\u5982\u679c\u5e93\u5b58\u5927\u4e8e0\uff0c\u5219\u5141\u8bb8\u501f\u9605\uff0c\u5e76\u81ea\u52a8\u5c06\u5e93\u5b58\u51cf1\u3002
\u8fd9\u6837\u53ef\u4ee5\u4fdd\u8bc1\u501f\u4e66\u65f6\u4e0d\u4f1a\u51fa\u73b0\u5e93\u5b58\u4e3a\u8d1f\u6570\u7684\u60c5\u51b5\u3002<\/pre>\n\n\n\n
\n\n\n\n4. \u9884\u7ea6\u56fe\u4e66\u529f\u80fd\u9700\u8981\u589e\u52a0\u54ea\u4e9b\u5b9e\u4f53\u548c\u5173\u7cfb\uff1f<\/h2>\n\n\n\n\u5982\u679c\u7cfb\u7edf\u652f\u6301\u9884\u7ea6\u56fe\u4e66\u529f\u80fd\uff0c\u53ef\u4ee5\u589e\u52a0 reservation \u9884\u7ea6\u8868\u3002
reservation(
reserveid,
rno,
bno,
reservedate,
status
)
\u5176\u4e2d\uff1a
reserveid \u8868\u793a\u9884\u7ea6\u7f16\u53f7\uff1b
rno \u662f\u8bfb\u8005\u8bc1\u53f7\uff0c\u5916\u952e\u5f15\u7528 reader.rno\uff1b
bno \u662f\u56fe\u4e66\u7f16\u53f7\uff0c\u5916\u952e\u5f15\u7528 book.bno\uff1b
reservedate \u8868\u793a\u9884\u7ea6\u65e5\u671f\uff1b
status \u8868\u793a\u9884\u7ea6\u72b6\u6001\uff0c\u5982\u201c\u9884\u7ea6\u4e2d\u201d\u201c\u5df2\u53d6\u6d88\u201d\u201c\u5df2\u5b8c\u6210\u201d\u3002
\u65b0\u589e\u5173\u7cfb\uff1a
\u4e00\u4e2a\u8bfb\u8005\u53ef\u4ee5\u9884\u7ea6\u591a\u672c\u56fe\u4e66\uff1b
\u4e00\u672c\u56fe\u4e66\u53ef\u4ee5\u88ab\u591a\u4e2a\u8bfb\u8005\u9884\u7ea6\uff1b
\u8bfb\u8005\u548c\u56fe\u4e66\u4e4b\u95f4\u901a\u8fc7 reservation \u8868\u5f62\u6210 m:n \u8054\u7cfb\u3002<\/pre>\n\n\n\n
\n\n\n\n5. \u4e3a\u4ec0\u4e48\u9075\u5faa\u6700\u5c0f\u6743\u9650\u539f\u5219\uff1f<\/h2>\n\n\n\n\u6700\u5c0f\u6743\u9650\u539f\u5219\u662f\u6307\u53ea\u7ed9\u7528\u6237\u5b8c\u6210\u5de5\u4f5c\u6240\u5fc5\u9700\u7684\u6743\u9650\uff0c\u4e0d\u6388\u4e88\u591a\u4f59\u6743\u9650\u3002
\u5728\u672c\u5b9e\u9a8c\u4e2d\uff0c\u5982\u679c\u67d0\u7528\u6237\u53ea\u8d1f\u8d23\u67e5\u8be2\u56fe\u4e66\u4fe1\u606f\uff0c\u5219\u53ea\u6388\u4e88 SELECT \u6743\u9650\u5373\u53ef\uff0c\u4e0d\u5e94\u8be5\u6388\u4e88 INSERT\u3001UPDATE\u3001DELETE \u7b49\u6743\u9650\u3002
\u4f8b\u5982\uff1a
GRANT SELECT ON library_db.book TO 'lib_user1'@'localhost';
\u8fd9\u6837\u53ef\u4ee5\u9632\u6b62\u7528\u6237\u8bef\u5220\u3001\u8bef\u6539\u6570\u636e\uff0c\u63d0\u9ad8\u6570\u636e\u5e93\u5b89\u5168\u6027\u3002
\u5982\u679c\u540e\u7eed\u4e0d\u518d\u9700\u8981\u67d0\u9879\u6743\u9650\uff0c\u8fd8\u53ef\u4ee5\u4f7f\u7528 REVOKE \u56de\u6536\u6743\u9650\u3002<\/pre>\n\n\n\n
\n\n\n\n6. \u5e76\u53d1\u501f\u9605\u5e93\u5b58\u4ec5\u52691\u672c\u7684\u56fe\u4e66\u4f1a\u4ea7\u751f\u4ec0\u4e48\u95ee\u9898\uff1f\u5982\u4f55\u89e3\u51b3\uff1f<\/h2>\n\n\n\n\u5f53\u591a\u7528\u6237\u540c\u65f6\u501f\u9605\u540c\u4e00\u672c\u5e93\u5b58\u4ec5\u52691\u672c\u7684\u56fe\u4e66\u65f6\uff0c\u53ef\u80fd\u51fa\u73b0\u8d85\u5356\u95ee\u9898\u3002
\u4f8b\u5982\u4e24\u4e2a\u7528\u6237\u540c\u65f6\u8bfb\u53d6\u5e93\u5b58 stock=1\uff0c\u90fd\u8ba4\u4e3a\u53ef\u4ee5\u501f\u9605\uff0c\u7136\u540e\u540c\u65f6\u63d2\u5165\u501f\u9605\u8bb0\u5f55\u5e76\u6267\u884c\u5e93\u5b58\u51cf1\uff0c\u6700\u7ec8\u53ef\u80fd\u5bfc\u81f4\u5e93\u5b58\u5f02\u5e38\u6216\u51fa\u73b0\u8d85\u989d\u501f\u9605\u3002
\u89e3\u51b3\u65b9\u6cd5\uff1a
1. \u4f7f\u7528\u4e8b\u52a1\u4fdd\u8bc1\u501f\u4e66\u64cd\u4f5c\u7684\u539f\u5b50\u6027\uff1b
2. \u4f7f\u7528 SELECT ... FOR UPDATE \u5bf9\u56fe\u4e66\u5e93\u5b58\u8bb0\u5f55\u52a0\u884c\u7ea7\u9501\uff1b
3. \u5728\u89e6\u53d1\u5668\u4e2d\u5224\u65ad\u5e93\u5b58\u662f\u5426\u5927\u4e8e0\uff1b
4. \u7ed9 stock \u5b57\u6bb5\u8bbe\u7f6e CHECK(stock >= 0) \u7ea6\u675f\u3002
\u793a\u4f8b\uff1a
START TRANSACTION;
SELECT stock
FROM book
WHERE bno='B001'
FOR UPDATE;
UPDATE book
SET stock = stock - 1
WHERE bno='B001'
AND stock > 0;
INSERT INTO borrow(rno,bno,borrowdate,returndate)
VALUES('R2024001','B001','2025-05-01','2025-05-15');
COMMIT;
\u8fd9\u6837\u53ef\u4ee5\u907f\u514d\u591a\u4e2a\u7528\u6237\u540c\u65f6\u4fee\u6539\u5e93\u5b58\u5bfc\u81f4\u6570\u636e\u4e0d\u4e00\u81f4\u3002<\/pre>\n\n\n\n
\n\n\n\n\u5b9e\u9a8c\u603b\u7ed3<\/h1>\n\n\n\n \u901a\u8fc7\u672c\u6b21\u56fe\u4e66\u501f\u9605\u7ba1\u7406\u7cfb\u7edf\u7efc\u5408\u5b9e\u9a8c\uff0c\u6211\u7cfb\u7edf\u5730\u5b8c\u6210\u4e86\u6570\u636e\u5e93\u8bbe\u8ba1\u4e0e\u5b9e\u73b0\u7684\u5168\u8fc7\u7a0b\u3002\u5b9e\u9a8c\u4ece\u9700\u6c42\u5206\u6790\u5f00\u59cb\uff0c\u9010\u6b65\u5b8c\u6210 E-R \u56fe\u8bbe\u8ba1\u3001\u5173\u7cfb\u6a21\u5f0f\u8f6c\u6362\u3001\u7269\u7406\u8868\u7ed3\u6784\u8bbe\u8ba1\u3001\u6570\u636e\u63d2\u5165\u3001\u67e5\u8be2\u64cd\u4f5c\u3001\u89c6\u56fe\u3001\u7d22\u5f15\u3001\u5b8c\u6574\u6027\u7ea6\u675f\u3001\u89e6\u53d1\u5668\u548c\u6743\u9650\u7ba1\u7406\u7b49\u5185\u5bb9\uff0c\u4f7f\u6211\u5bf9\u6570\u636e\u5e93\u5e94\u7528\u7cfb\u7edf\u7684\u8bbe\u8ba1\u6d41\u7a0b\u6709\u4e86\u66f4\u52a0\u5b8c\u6574\u7684\u8ba4\u8bc6\u3002
\u200b
\u5728\u5b9e\u9a8c\u8fc7\u7a0b\u4e2d\uff0c\u6211\u9996\u5148\u6839\u636e\u56fe\u4e66\u9986\u4e1a\u52a1\u9700\u6c42\u5206\u6790\u51fa\u56fe\u4e66\u3001\u8bfb\u8005\u3001\u501f\u9605\u3001\u51fa\u7248\u793e\u3001\u5206\u7c7b\u7b49\u5b9e\u4f53\uff0c\u5e76\u660e\u786e\u4e86\u5b83\u4eec\u4e4b\u95f4\u7684\u8054\u7cfb\u7c7b\u578b\u3002\u4f8b\u5982\uff0c\u51fa\u7248\u793e\u4e0e\u56fe\u4e66\u4e4b\u95f4\u662f\u4e00\u5bf9\u591a\u5173\u7cfb\uff0c\u5206\u7c7b\u4e0e\u56fe\u4e66\u4e4b\u95f4\u662f\u4e00\u5bf9\u591a\u5173\u7cfb\uff0c\u8bfb\u8005\u4e0e\u56fe\u4e66\u4e4b\u95f4\u901a\u8fc7\u501f\u9605\u8868\u5f62\u6210\u591a\u5bf9\u591a\u5173\u7cfb\u3002\u901a\u8fc7 E-R \u56fe\u8bbe\u8ba1\uff0c\u6211\u8fdb\u4e00\u6b65\u7406\u89e3\u4e86\u6982\u5ff5\u7ed3\u6784\u8bbe\u8ba1\u5728\u6570\u636e\u5e93\u5f00\u53d1\u4e2d\u7684\u91cd\u8981\u4f5c\u7528\u3002
\u200b
\u5728\u903b\u8f91\u7ed3\u6784\u8bbe\u8ba1\u9636\u6bb5\uff0c\u6211\u5c06 E-R \u56fe\u8f6c\u6362\u4e3a\u5173\u7cfb\u6a21\u5f0f\uff0c\u5e76\u5206\u6790\u5404\u8868\u662f\u5426\u6ee1\u8db3\u7b2c\u4e09\u8303\u5f0f\u3002\u901a\u8fc7\u89c4\u8303\u5316\u8bbe\u8ba1\uff0c\u907f\u514d\u4e86\u5728\u501f\u9605\u8868\u4e2d\u91cd\u590d\u4fdd\u5b58\u8bfb\u8005\u59d3\u540d\u3001\u56fe\u4e66\u540d\u79f0\u7b49\u4fe1\u606f\uff0c\u51cf\u5c11\u4e86\u6570\u636e\u5197\u4f59\uff0c\u63d0\u9ad8\u4e86\u6570\u636e\u4e00\u81f4\u6027\u3002\u5728\u7269\u7406\u8bbe\u8ba1\u9636\u6bb5\uff0c\u6211\u4f7f\u7528 SQL \u521b\u5efa\u6570\u636e\u5e93\u548c\u6570\u636e\u8868\uff0c\u8bbe\u7f6e\u4e86\u4e3b\u952e\u3001\u5916\u952e\u3001\u975e\u7a7a\u3001\u9ed8\u8ba4\u503c\u548c CHECK \u7ea6\u675f\uff0c\u5bf9\u5b9e\u4f53\u5b8c\u6574\u6027\u3001\u53c2\u7167\u5b8c\u6574\u6027\u548c\u7528\u6237\u5b9a\u4e49\u5b8c\u6574\u6027\u6709\u4e86\u66f4\u6df1\u523b\u7684\u7406\u89e3\u3002
\u200b
\u5728\u6570\u636e\u64cd\u4f5c\u90e8\u5206\uff0c\u6211\u7ec3\u4e60\u4e86 INSERT\u3001UPDATE\u3001DELETE \u548c SELECT \u8bed\u53e5\uff0c\u5e76\u5b8c\u6210\u4e86\u57fa\u7840\u67e5\u8be2\u3001\u805a\u5408\u67e5\u8be2\u3001\u591a\u8868\u8fde\u63a5\u67e5\u8be2\u3001\u5d4c\u5957\u67e5\u8be2\u548c\u96c6\u5408\u67e5\u8be2\u7b49\u5185\u5bb9\u3002\u901a\u8fc7\u8fd9\u4e9b\u7ec3\u4e60\uff0c\u6211\u638c\u63e1\u4e86 SQL \u67e5\u8be2\u8bed\u53e5\u7684\u5e38\u89c1\u5199\u6cd5\uff0c\u5c24\u5176\u662f\u591a\u8868\u8fde\u63a5\u548c\u5d4c\u5957\u67e5\u8be2\u7684\u4f7f\u7528\u65b9\u6cd5\u3002\u5b9e\u9a8c\u4e2d\u8fd8\u521b\u5efa\u4e86\u89c6\u56fe\u548c\u7d22\u5f15\uff0c\u7406\u89e3\u4e86\u89c6\u56fe\u53ef\u4ee5\u7b80\u5316\u590d\u6742\u67e5\u8be2\uff0c\u7d22\u5f15\u53ef\u4ee5\u63d0\u9ad8\u67e5\u8be2\u6548\u7387\uff0c\u4f46\u4e5f\u4f1a\u589e\u52a0\u7ef4\u62a4\u6210\u672c\u3002
\u200b
\u5728\u89e6\u53d1\u5668\u90e8\u5206\uff0c\u6211\u5b9e\u73b0\u4e86\u501f\u4e66\u81ea\u52a8\u51cf\u5c11\u5e93\u5b58\u3001\u8fd8\u4e66\u81ea\u52a8\u589e\u52a0\u5e93\u5b58\u5e76\u8ba1\u7b97\u7f5a\u6b3e\u3001\u5220\u9664\u8bfb\u8005\u524d\u8bb0\u5f55\u65e5\u5fd7\u7b49\u529f\u80fd\u3002\u901a\u8fc7\u89e6\u53d1\u5668\u5b9e\u9a8c\uff0c\u6211\u8ba4\u8bc6\u5230\u6570\u636e\u5e93\u4e0d\u4ec5\u53ef\u4ee5\u5b58\u50a8\u6570\u636e\uff0c\u8fd8\u53ef\u4ee5\u5728\u7279\u5b9a\u64cd\u4f5c\u53d1\u751f\u65f6\u81ea\u52a8\u6267\u884c\u4e00\u4e9b\u4e1a\u52a1\u903b\u8f91\u3002\u5b9e\u9a8c\u8fc7\u7a0b\u4e2d\u4e5f\u9047\u5230\u4e86\u4e00\u4e9b\u95ee\u9898\uff0c\u4f8b\u5982\u5916\u952e\u7ea6\u675f\u5bfc\u81f4\u6570\u636e\u65e0\u6cd5\u5220\u9664\u3001CHECK \u7ea6\u675f\u63d2\u5165\u5931\u8d25\u3001\u89e6\u53d1\u5668\u8bed\u6cd5\u9519\u8bef\u7b49\u3002\u901a\u8fc7\u67e5\u770b\u9519\u8bef\u4fe1\u606f\u3001\u4fee\u6539 SQL \u8bed\u53e5\u548c\u53cd\u590d\u6d4b\u8bd5\uff0c\u6700\u7ec8\u89e3\u51b3\u4e86\u8fd9\u4e9b\u95ee\u9898\u3002
\u200b
\u901a\u8fc7\u672c\u6b21\u5b9e\u9a8c\uff0c\u6211\u4e0d\u4ec5\u5de9\u56fa\u4e86\u6570\u636e\u5e93\u7406\u8bba\u77e5\u8bc6\uff0c\u4e5f\u63d0\u9ad8\u4e86 SQL \u7f16\u5199\u80fd\u529b\u548c\u6570\u636e\u5e93\u8c03\u8bd5\u80fd\u529b\u3002\u4eca\u540e\u5728\u8bbe\u8ba1\u6570\u636e\u5e93\u7cfb\u7edf<\/pre>\n","protected":false},"excerpt":{"rendered":"\u6570\u636e\u5e93\u7efc\u5408\u5b9e\u9a8c 1.\u9700\u6c42\u5206\u6790 \u67d0\u5927\u578b\u56fe\u4e66\u9986\u9700\u8981\u5f00\u53d1\u4e00\u5957\u6570\u5b57\u5316\u501f\u9605\u7ba1\u7406\u7cfb\u7edf\uff0c\u4e3b\u8981\u4e1a\u52a1\u9700\u6c42\u5982\u4e0b\uff1a \u56fe\u4e66\u4fe1\u606f\uff1a\u8bb0\u5f55\u56fe […]<\/p>\n","protected":false},"author":1,"featured_media":448,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[9],"tags":[],"class_list":["post-446","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-wenzhang"],"_links":{"self":[{"href":"https:\/\/fg2025.cn\/index.php\/wp-json\/wp\/v2\/posts\/446","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/fg2025.cn\/index.php\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/fg2025.cn\/index.php\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/fg2025.cn\/index.php\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/fg2025.cn\/index.php\/wp-json\/wp\/v2\/comments?post=446"}],"version-history":[{"count":0,"href":"https:\/\/fg2025.cn\/index.php\/wp-json\/wp\/v2\/posts\/446\/revisions"}],"wp:attachment":[{"href":"https:\/\/fg2025.cn\/index.php\/wp-json\/wp\/v2\/media?parent=446"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/fg2025.cn\/index.php\/wp-json\/wp\/v2\/categories?post=446"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/fg2025.cn\/index.php\/wp-json\/wp\/v2\/tags?post=446"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}
DROP TRIGGER IF EXISTS trg_borrow_before_insert;
DROP TRIGGER IF EXISTS trg_return_after_update;
DROP TRIGGER IF EXISTS trg_reader_before_delete;
\u521b\u5efa\u5220\u9664\u8bfb\u8005\u65e5\u5fd7\u8868
CREATE TABLE reader_delete_log(
logid INT AUTO_INCREMENT PRIMARY KEY,
rno CHAR(12),
rname VARCHAR(20),
dept VARCHAR(40),
delete_time DATETIME DEFAULT CURRENT_TIMESTAMP
);
1.\u501f\u4e66\u65f6\u81ea\u52a8\u51cf\u5c11\u5e93\u5b58
DELIMITER \/\/
CREATE TRIGGER trg_borrow_before_insert
BEFORE INSERT ON borrow
FOR EACH ROW
BEGIN
DECLARE v_stock INT;
SELECT stock INTO v_stock
FROM book
WHERE bno = NEW.bno;
IF v_stock <= 0 THEN
SIGNAL SQLSTATE '45000'
SET MESSAGE_TEXT = '\u5e93\u5b58\u4e0d\u8db3\uff0c\u4e0d\u80fd\u501f\u4e66';
ELSE
UPDATE book
SET stock = stock - 1
WHERE bno = NEW.bno;
END IF;
END \/\/
DELIMITER ;
\u6d4b\u8bd5\uff1a
SELECT stock FROM book WHERE bno='B003';
INSERT INTO borrow(rno,bno,borrowdate,returndate,actualdate)
VALUES('R2024002','B003','2025-05-01','2025-05-15',NULL);
SELECT stock FROM book WHERE bno='B003';
2.\u8fd8\u4e66\u65f6\u81ea\u52a8\u589e\u52a0\u5e93\u5b58\u5e76\u8ba1\u7b97\u7f5a\u6b3e
DELIMITER \/\/
CREATE TRIGGER trg_return_after_update
AFTER UPDATE ON borrow
FOR EACH ROW
BEGIN
IF OLD.actualdate IS NULL AND NEW.actualdate IS NOT NULL THEN
UPDATE book
SET stock = stock + 1
WHERE bno = NEW.bno;
UPDATE borrow
SET fine =
CASE
WHEN NEW.actualdate > NEW.returndate
THEN DATEDIFF(NEW.actualdate, NEW.returndate) * 1
ELSE 0
END
WHERE borrowid = NEW.borrowid;
END IF;
END \/\/
DELIMITER ;
\u6d4b\u8bd5\uff1a
UPDATE borrow
SET actualdate = '2025-05-18'
WHERE rno='R2024002'
AND bno='B003'
AND borrowdate='2025-05-01';
SELECT * FROM borrow
WHERE rno='R2024002'
AND bno='B003';
SELECT stock FROM book WHERE bno='B003';
3.\u5220\u9664\u8bfb\u8005\u524d\u8bb0\u5f55\u65e5\u5fd7
DELIMITER \/\/
CREATE TRIGGER trg_reader_before_delete
BEFORE DELETE ON reader
FOR EACH ROW
BEGIN
INSERT INTO reader_delete_log(rno,rname,dept)
VALUES(OLD.rno, OLD.rname, OLD.dept);
END \/\/
DELIMITER ;
\u6d4b\u8bd5\uff1a
INSERT INTO reader
VALUES('R2024888','\u65e5\u5fd7\u6d4b\u8bd5','\u7537','\u6d4b\u8bd5\u5b66\u9662','\u65e0');
DELETE FROM reader
WHERE rno='R2024888';
SELECT * FROM reader_delete_log;<\/pre>\n\n\n\n
15.\u6570\u636e\u5b89\u5168\u6027<\/h2>\n\n\n\n1.\u521b\u5efa\u7528\u6237\u5e76\u6388\u4e88\u67e5\u8be2\u6743\u9650
CREATE USER 'lib_user1'@'localhost'
IDENTIFIED BY '123456';
GRANT SELECT
ON library_db.book
TO 'lib_user1'@'localhost';
\u67e5\u770b\u6743\u9650\uff1a
SHOW GRANTS FOR 'lib_user1'@'localhost';
2.\u6388\u4e88\u6743\u9650\u5e76\u5141\u8bb8\u8f6c\u6388\u6743
GRANT SELECT, INSERT
ON library_db.reader
TO 'lib_user1'@'localhost'
WITH GRANT OPTION;
\u8bf4\u660e\uff1a
WITH GRANT OPTION \u8868\u793a\u8be5\u7528\u6237\u53ef\u4ee5\u5c06\u81ea\u5df1\u62e5\u6709\u7684\u6743\u9650\u518d\u6388\u4e88\u5176\u4ed6\u7528\u6237\u3002
3.\u56de\u6536\u6743\u9650
REVOKE INSERT
ON library_db.reader
FROM 'lib_user1'@'localhost';
4.\u521b\u5efa\u89d2\u8272\u5e76\u6388\u6743
CREATE ROLE 'reader_role';
GRANT SELECT
ON library_db.*
TO 'reader_role';
CREATE USER 'lib_user2'@'localhost'
IDENTIFIED BY '123456';
GRANT 'reader_role'
TO 'lib_user2'@'localhost';
SET DEFAULT ROLE 'reader_role'
TO 'lib_user2'@'localhost';<\/pre>\n\n\n\n16.\u89c6\u56fe\u4e0e\u6d3e\u751f\u8868<\/h2>\n\n\n\n1.\u5e26\u805a\u5408\u51fd\u6570\u7684\u89c6\u56fe\uff1a\u7edf\u8ba1\u6bcf\u4e2a\u8bfb\u8005\u501f\u9605\u6b21\u6570
CREATE VIEW v_reader_borrow_count AS
SELECT r.rno, r.rname, COUNT(br.borrowid) AS borrow_count
FROM reader r
LEFT JOIN borrow br
ON r.rno = br.rno
GROUP BY r.rno, r.rname;
\u67e5\u8be2\uff1a
SELECT * FROM v_reader_borrow_count;
2.\u6d3e\u751f\u8868\uff1a\u67e5\u8be2\u501f\u9605\u6b21\u6570\u5927\u4e8e1\u7684\u8bfb\u8005
SELECT *
FROM (
SELECT rno, COUNT(*) AS borrow_count
FROM borrow
GROUP BY rno
) AS t
WHERE t.borrow_count > 1;
3.WITH \u5b50\u53e5\u7edf\u8ba1\u6bcf\u4f4d\u8bfb\u8005\u501f\u9605\u6570\u91cf
WITH reader_count AS (
SELECT rno, COUNT(*) AS total
FROM borrow
GROUP BY rno
)
SELECT r.rno, r.rname, rc.total
FROM reader r
LEFT JOIN reader_count rc
ON r.rno = rc.rno;
4.WITH \u5b50\u53e5\uff1a\u67e5\u8be2\u672a\u5f52\u8fd8\u56fe\u4e66
WITH unreturned AS (
SELECT br.borrowid, r.rname, b.bname,
br.borrowdate, br.returndate
FROM borrow br
JOIN reader r ON br.rno = r.rno
JOIN book b ON br.bno = b.bno
WHERE br.actualdate IS NULL
)
SELECT * FROM unreturned;<\/pre>\n\n\n\n17.\u6269\u5c55\u601d\u8003<\/h2>\n\n\n\n\n- \u5982\u4f55\u5904\u7406\u5206\u7c7b\u5b9e\u4f53\u7684\u81ea\u5173\u8054\uff1f<\/li>\n<\/ol>\n\n\n\n
\u5206\u7c7b\u5b9e\u4f53\u5b58\u5728\u201c\u4e0a\u7ea7\u5206\u7c7b\u201d\u548c\u201c\u4e0b\u7ea7\u5206\u7c7b\u201d\u7684\u5173\u7cfb\uff0c\u56e0\u6b64\u53ef\u4ee5\u5728 category \u8868\u4e2d\u8bbe\u7f6e parentid \u5b57\u6bb5\u3002
category(
cid,
cname,
parentid
)
\u5176\u4e2d cid \u662f\u5206\u7c7b\u7f16\u53f7\uff0cparentid \u662f\u4e0a\u7ea7\u5206\u7c7b\u7f16\u53f7\uff0c\u540c\u65f6 parentid \u4e5f\u662f\u6307\u5411 category.cid \u7684\u5916\u952e\u3002
\u5982\u679c\u67d0\u5206\u7c7b\u6ca1\u6709\u4e0a\u7ea7\u5206\u7c7b\uff0c\u5219 parentid \u53ef\u4ee5\u4e3a\u7a7a\u3002
\u8fd9\u79cd\u8bbe\u8ba1\u53ef\u4ee5\u8868\u793a\u6811\u5f62\u7ed3\u6784\uff0c\u4f8b\u5982\uff1a
\u56fe\u4e66
\u251c\u2500\u2500 \u8ba1\u7b97\u673a
\u2502 \u251c\u2500\u2500 \u6570\u636e\u5e93
\u2502 \u2514\u2500\u2500 \u7f51\u7edc\u6280\u672f
\u2514\u2500\u2500 \u6587\u5b66
\u2514\u2500\u2500 \u79d1\u5e7b\u5c0f\u8bf4<\/pre>\n\n\n\n
\n\n\n\n2. \u501f\u9605\u5173\u7cfb\u662f\u5426\u53ef\u80fd\u5b58\u5728\u6570\u636e\u5197\u4f59\uff1f<\/h2>\n\n\n\n\u501f\u9605\u8868\u5982\u679c\u53ea\u4fdd\u5b58 rno\u3001bno\u3001borrowdate\u3001returndate\u3001actualdate \u7b49\u4fe1\u606f\uff0c\u5219\u5197\u4f59\u8f83\u5c11\u3002
\u4f46\u662f\u5982\u679c\u5728 borrow \u8868\u4e2d\u540c\u65f6\u4fdd\u5b58\u8bfb\u8005\u59d3\u540d rname\u3001\u56fe\u4e66\u540d\u79f0 bname\u3001\u51fa\u7248\u793e press \u7b49\u4fe1\u606f\uff0c\u5c31\u4f1a\u4ea7\u751f\u6570\u636e\u5197\u4f59\u3002
\u4f8b\u5982\uff1a
borrow(borrowid, rno, rname, bno, bname, borrowdate)
\u5176\u4e2d rname \u4f9d\u8d56 rno\uff0cbname \u4f9d\u8d56 bno\uff0c\u800c\u4e0d\u662f\u76f4\u63a5\u4f9d\u8d56 borrowid\uff0c\u4f1a\u4ea7\u751f\u4f20\u9012\u4f9d\u8d56\u3002
\u89c4\u8303\u5316\u65b9\u6848\uff1a
\u5c06\u8bfb\u8005\u4fe1\u606f\u4fdd\u5b58\u5728 reader \u8868\uff1b
\u5c06\u56fe\u4e66\u4fe1\u606f\u4fdd\u5b58\u5728 book \u8868\uff1b
borrow \u8868\u53ea\u4fdd\u5b58\u8bfb\u8005\u8bc1\u53f7\u548c\u56fe\u4e66\u7f16\u53f7\u4f5c\u4e3a\u5916\u952e\u3002<\/pre>\n\n\n\n
\n\n\n\n3. \u5982\u4f55\u9632\u6b62\u5e93\u5b58\u4e3a\u8d1f\u6570\uff1f<\/h2>\n\n\n\n\u53ef\u4ee5\u4ece\u4e24\u4e2a\u65b9\u9762\u9632\u6b62\u5e93\u5b58\u4e3a\u8d1f\u6570\uff1a
\u7b2c\u4e00\uff0c\u5728 book \u8868\u4e2d\u8bbe\u7f6e CHECK(stock >= 0) \u7ea6\u675f\uff0c\u4fdd\u8bc1\u5e93\u5b58\u4e0d\u80fd\u5c0f\u4e8e0\u3002
\u7b2c\u4e8c\uff0c\u5728\u501f\u4e66\u89e6\u53d1\u5668\u4e2d\u5224\u65ad\u5e93\u5b58\u6570\u91cf\u3002
\u5f53\u63d2\u5165 borrow \u501f\u9605\u8bb0\u5f55\u65f6\uff0c\u5148\u67e5\u8be2\u56fe\u4e66\u5e93\u5b58\u3002
\u5982\u679c\u5e93\u5b58\u5c0f\u4e8e\u7b49\u4e8e0\uff0c\u5219\u4f7f\u7528 SIGNAL \u629b\u51fa\u9519\u8bef\uff0c\u963b\u6b62\u501f\u4e66\u64cd\u4f5c\uff1b
\u5982\u679c\u5e93\u5b58\u5927\u4e8e0\uff0c\u5219\u5141\u8bb8\u501f\u9605\uff0c\u5e76\u81ea\u52a8\u5c06\u5e93\u5b58\u51cf1\u3002
\u8fd9\u6837\u53ef\u4ee5\u4fdd\u8bc1\u501f\u4e66\u65f6\u4e0d\u4f1a\u51fa\u73b0\u5e93\u5b58\u4e3a\u8d1f\u6570\u7684\u60c5\u51b5\u3002<\/pre>\n\n\n\n
\n\n\n\n4. \u9884\u7ea6\u56fe\u4e66\u529f\u80fd\u9700\u8981\u589e\u52a0\u54ea\u4e9b\u5b9e\u4f53\u548c\u5173\u7cfb\uff1f<\/h2>\n\n\n\n\u5982\u679c\u7cfb\u7edf\u652f\u6301\u9884\u7ea6\u56fe\u4e66\u529f\u80fd\uff0c\u53ef\u4ee5\u589e\u52a0 reservation \u9884\u7ea6\u8868\u3002
reservation(
reserveid,
rno,
bno,
reservedate,
status
)
\u5176\u4e2d\uff1a
reserveid \u8868\u793a\u9884\u7ea6\u7f16\u53f7\uff1b
rno \u662f\u8bfb\u8005\u8bc1\u53f7\uff0c\u5916\u952e\u5f15\u7528 reader.rno\uff1b
bno \u662f\u56fe\u4e66\u7f16\u53f7\uff0c\u5916\u952e\u5f15\u7528 book.bno\uff1b
reservedate \u8868\u793a\u9884\u7ea6\u65e5\u671f\uff1b
status \u8868\u793a\u9884\u7ea6\u72b6\u6001\uff0c\u5982\u201c\u9884\u7ea6\u4e2d\u201d\u201c\u5df2\u53d6\u6d88\u201d\u201c\u5df2\u5b8c\u6210\u201d\u3002
\u65b0\u589e\u5173\u7cfb\uff1a
\u4e00\u4e2a\u8bfb\u8005\u53ef\u4ee5\u9884\u7ea6\u591a\u672c\u56fe\u4e66\uff1b
\u4e00\u672c\u56fe\u4e66\u53ef\u4ee5\u88ab\u591a\u4e2a\u8bfb\u8005\u9884\u7ea6\uff1b
\u8bfb\u8005\u548c\u56fe\u4e66\u4e4b\u95f4\u901a\u8fc7 reservation \u8868\u5f62\u6210 m:n \u8054\u7cfb\u3002<\/pre>\n\n\n\n
\n\n\n\n5. \u4e3a\u4ec0\u4e48\u9075\u5faa\u6700\u5c0f\u6743\u9650\u539f\u5219\uff1f<\/h2>\n\n\n\n\u6700\u5c0f\u6743\u9650\u539f\u5219\u662f\u6307\u53ea\u7ed9\u7528\u6237\u5b8c\u6210\u5de5\u4f5c\u6240\u5fc5\u9700\u7684\u6743\u9650\uff0c\u4e0d\u6388\u4e88\u591a\u4f59\u6743\u9650\u3002
\u5728\u672c\u5b9e\u9a8c\u4e2d\uff0c\u5982\u679c\u67d0\u7528\u6237\u53ea\u8d1f\u8d23\u67e5\u8be2\u56fe\u4e66\u4fe1\u606f\uff0c\u5219\u53ea\u6388\u4e88 SELECT \u6743\u9650\u5373\u53ef\uff0c\u4e0d\u5e94\u8be5\u6388\u4e88 INSERT\u3001UPDATE\u3001DELETE \u7b49\u6743\u9650\u3002
\u4f8b\u5982\uff1a
GRANT SELECT ON library_db.book TO 'lib_user1'@'localhost';
\u8fd9\u6837\u53ef\u4ee5\u9632\u6b62\u7528\u6237\u8bef\u5220\u3001\u8bef\u6539\u6570\u636e\uff0c\u63d0\u9ad8\u6570\u636e\u5e93\u5b89\u5168\u6027\u3002
\u5982\u679c\u540e\u7eed\u4e0d\u518d\u9700\u8981\u67d0\u9879\u6743\u9650\uff0c\u8fd8\u53ef\u4ee5\u4f7f\u7528 REVOKE \u56de\u6536\u6743\u9650\u3002<\/pre>\n\n\n\n
\n\n\n\n6. \u5e76\u53d1\u501f\u9605\u5e93\u5b58\u4ec5\u52691\u672c\u7684\u56fe\u4e66\u4f1a\u4ea7\u751f\u4ec0\u4e48\u95ee\u9898\uff1f\u5982\u4f55\u89e3\u51b3\uff1f<\/h2>\n\n\n\n\u5f53\u591a\u7528\u6237\u540c\u65f6\u501f\u9605\u540c\u4e00\u672c\u5e93\u5b58\u4ec5\u52691\u672c\u7684\u56fe\u4e66\u65f6\uff0c\u53ef\u80fd\u51fa\u73b0\u8d85\u5356\u95ee\u9898\u3002
\u4f8b\u5982\u4e24\u4e2a\u7528\u6237\u540c\u65f6\u8bfb\u53d6\u5e93\u5b58 stock=1\uff0c\u90fd\u8ba4\u4e3a\u53ef\u4ee5\u501f\u9605\uff0c\u7136\u540e\u540c\u65f6\u63d2\u5165\u501f\u9605\u8bb0\u5f55\u5e76\u6267\u884c\u5e93\u5b58\u51cf1\uff0c\u6700\u7ec8\u53ef\u80fd\u5bfc\u81f4\u5e93\u5b58\u5f02\u5e38\u6216\u51fa\u73b0\u8d85\u989d\u501f\u9605\u3002
\u89e3\u51b3\u65b9\u6cd5\uff1a
1. \u4f7f\u7528\u4e8b\u52a1\u4fdd\u8bc1\u501f\u4e66\u64cd\u4f5c\u7684\u539f\u5b50\u6027\uff1b
2. \u4f7f\u7528 SELECT ... FOR UPDATE \u5bf9\u56fe\u4e66\u5e93\u5b58\u8bb0\u5f55\u52a0\u884c\u7ea7\u9501\uff1b
3. \u5728\u89e6\u53d1\u5668\u4e2d\u5224\u65ad\u5e93\u5b58\u662f\u5426\u5927\u4e8e0\uff1b
4. \u7ed9 stock \u5b57\u6bb5\u8bbe\u7f6e CHECK(stock >= 0) \u7ea6\u675f\u3002
\u793a\u4f8b\uff1a
START TRANSACTION;
SELECT stock
FROM book
WHERE bno='B001'
FOR UPDATE;
UPDATE book
SET stock = stock - 1
WHERE bno='B001'
AND stock > 0;
INSERT INTO borrow(rno,bno,borrowdate,returndate)
VALUES('R2024001','B001','2025-05-01','2025-05-15');
COMMIT;
\u8fd9\u6837\u53ef\u4ee5\u907f\u514d\u591a\u4e2a\u7528\u6237\u540c\u65f6\u4fee\u6539\u5e93\u5b58\u5bfc\u81f4\u6570\u636e\u4e0d\u4e00\u81f4\u3002<\/pre>\n\n\n\n
\n\n\n\n\u5b9e\u9a8c\u603b\u7ed3<\/h1>\n\n\n\n \u901a\u8fc7\u672c\u6b21\u56fe\u4e66\u501f\u9605\u7ba1\u7406\u7cfb\u7edf\u7efc\u5408\u5b9e\u9a8c\uff0c\u6211\u7cfb\u7edf\u5730\u5b8c\u6210\u4e86\u6570\u636e\u5e93\u8bbe\u8ba1\u4e0e\u5b9e\u73b0\u7684\u5168\u8fc7\u7a0b\u3002\u5b9e\u9a8c\u4ece\u9700\u6c42\u5206\u6790\u5f00\u59cb\uff0c\u9010\u6b65\u5b8c\u6210 E-R \u56fe\u8bbe\u8ba1\u3001\u5173\u7cfb\u6a21\u5f0f\u8f6c\u6362\u3001\u7269\u7406\u8868\u7ed3\u6784\u8bbe\u8ba1\u3001\u6570\u636e\u63d2\u5165\u3001\u67e5\u8be2\u64cd\u4f5c\u3001\u89c6\u56fe\u3001\u7d22\u5f15\u3001\u5b8c\u6574\u6027\u7ea6\u675f\u3001\u89e6\u53d1\u5668\u548c\u6743\u9650\u7ba1\u7406\u7b49\u5185\u5bb9\uff0c\u4f7f\u6211\u5bf9\u6570\u636e\u5e93\u5e94\u7528\u7cfb\u7edf\u7684\u8bbe\u8ba1\u6d41\u7a0b\u6709\u4e86\u66f4\u52a0\u5b8c\u6574\u7684\u8ba4\u8bc6\u3002
\u200b
\u5728\u5b9e\u9a8c\u8fc7\u7a0b\u4e2d\uff0c\u6211\u9996\u5148\u6839\u636e\u56fe\u4e66\u9986\u4e1a\u52a1\u9700\u6c42\u5206\u6790\u51fa\u56fe\u4e66\u3001\u8bfb\u8005\u3001\u501f\u9605\u3001\u51fa\u7248\u793e\u3001\u5206\u7c7b\u7b49\u5b9e\u4f53\uff0c\u5e76\u660e\u786e\u4e86\u5b83\u4eec\u4e4b\u95f4\u7684\u8054\u7cfb\u7c7b\u578b\u3002\u4f8b\u5982\uff0c\u51fa\u7248\u793e\u4e0e\u56fe\u4e66\u4e4b\u95f4\u662f\u4e00\u5bf9\u591a\u5173\u7cfb\uff0c\u5206\u7c7b\u4e0e\u56fe\u4e66\u4e4b\u95f4\u662f\u4e00\u5bf9\u591a\u5173\u7cfb\uff0c\u8bfb\u8005\u4e0e\u56fe\u4e66\u4e4b\u95f4\u901a\u8fc7\u501f\u9605\u8868\u5f62\u6210\u591a\u5bf9\u591a\u5173\u7cfb\u3002\u901a\u8fc7 E-R \u56fe\u8bbe\u8ba1\uff0c\u6211\u8fdb\u4e00\u6b65\u7406\u89e3\u4e86\u6982\u5ff5\u7ed3\u6784\u8bbe\u8ba1\u5728\u6570\u636e\u5e93\u5f00\u53d1\u4e2d\u7684\u91cd\u8981\u4f5c\u7528\u3002
\u200b
\u5728\u903b\u8f91\u7ed3\u6784\u8bbe\u8ba1\u9636\u6bb5\uff0c\u6211\u5c06 E-R \u56fe\u8f6c\u6362\u4e3a\u5173\u7cfb\u6a21\u5f0f\uff0c\u5e76\u5206\u6790\u5404\u8868\u662f\u5426\u6ee1\u8db3\u7b2c\u4e09\u8303\u5f0f\u3002\u901a\u8fc7\u89c4\u8303\u5316\u8bbe\u8ba1\uff0c\u907f\u514d\u4e86\u5728\u501f\u9605\u8868\u4e2d\u91cd\u590d\u4fdd\u5b58\u8bfb\u8005\u59d3\u540d\u3001\u56fe\u4e66\u540d\u79f0\u7b49\u4fe1\u606f\uff0c\u51cf\u5c11\u4e86\u6570\u636e\u5197\u4f59\uff0c\u63d0\u9ad8\u4e86\u6570\u636e\u4e00\u81f4\u6027\u3002\u5728\u7269\u7406\u8bbe\u8ba1\u9636\u6bb5\uff0c\u6211\u4f7f\u7528 SQL \u521b\u5efa\u6570\u636e\u5e93\u548c\u6570\u636e\u8868\uff0c\u8bbe\u7f6e\u4e86\u4e3b\u952e\u3001\u5916\u952e\u3001\u975e\u7a7a\u3001\u9ed8\u8ba4\u503c\u548c CHECK \u7ea6\u675f\uff0c\u5bf9\u5b9e\u4f53\u5b8c\u6574\u6027\u3001\u53c2\u7167\u5b8c\u6574\u6027\u548c\u7528\u6237\u5b9a\u4e49\u5b8c\u6574\u6027\u6709\u4e86\u66f4\u6df1\u523b\u7684\u7406\u89e3\u3002
\u200b
\u5728\u6570\u636e\u64cd\u4f5c\u90e8\u5206\uff0c\u6211\u7ec3\u4e60\u4e86 INSERT\u3001UPDATE\u3001DELETE \u548c SELECT \u8bed\u53e5\uff0c\u5e76\u5b8c\u6210\u4e86\u57fa\u7840\u67e5\u8be2\u3001\u805a\u5408\u67e5\u8be2\u3001\u591a\u8868\u8fde\u63a5\u67e5\u8be2\u3001\u5d4c\u5957\u67e5\u8be2\u548c\u96c6\u5408\u67e5\u8be2\u7b49\u5185\u5bb9\u3002\u901a\u8fc7\u8fd9\u4e9b\u7ec3\u4e60\uff0c\u6211\u638c\u63e1\u4e86 SQL \u67e5\u8be2\u8bed\u53e5\u7684\u5e38\u89c1\u5199\u6cd5\uff0c\u5c24\u5176\u662f\u591a\u8868\u8fde\u63a5\u548c\u5d4c\u5957\u67e5\u8be2\u7684\u4f7f\u7528\u65b9\u6cd5\u3002\u5b9e\u9a8c\u4e2d\u8fd8\u521b\u5efa\u4e86\u89c6\u56fe\u548c\u7d22\u5f15\uff0c\u7406\u89e3\u4e86\u89c6\u56fe\u53ef\u4ee5\u7b80\u5316\u590d\u6742\u67e5\u8be2\uff0c\u7d22\u5f15\u53ef\u4ee5\u63d0\u9ad8\u67e5\u8be2\u6548\u7387\uff0c\u4f46\u4e5f\u4f1a\u589e\u52a0\u7ef4\u62a4\u6210\u672c\u3002
\u200b
\u5728\u89e6\u53d1\u5668\u90e8\u5206\uff0c\u6211\u5b9e\u73b0\u4e86\u501f\u4e66\u81ea\u52a8\u51cf\u5c11\u5e93\u5b58\u3001\u8fd8\u4e66\u81ea\u52a8\u589e\u52a0\u5e93\u5b58\u5e76\u8ba1\u7b97\u7f5a\u6b3e\u3001\u5220\u9664\u8bfb\u8005\u524d\u8bb0\u5f55\u65e5\u5fd7\u7b49\u529f\u80fd\u3002\u901a\u8fc7\u89e6\u53d1\u5668\u5b9e\u9a8c\uff0c\u6211\u8ba4\u8bc6\u5230\u6570\u636e\u5e93\u4e0d\u4ec5\u53ef\u4ee5\u5b58\u50a8\u6570\u636e\uff0c\u8fd8\u53ef\u4ee5\u5728\u7279\u5b9a\u64cd\u4f5c\u53d1\u751f\u65f6\u81ea\u52a8\u6267\u884c\u4e00\u4e9b\u4e1a\u52a1\u903b\u8f91\u3002\u5b9e\u9a8c\u8fc7\u7a0b\u4e2d\u4e5f\u9047\u5230\u4e86\u4e00\u4e9b\u95ee\u9898\uff0c\u4f8b\u5982\u5916\u952e\u7ea6\u675f\u5bfc\u81f4\u6570\u636e\u65e0\u6cd5\u5220\u9664\u3001CHECK \u7ea6\u675f\u63d2\u5165\u5931\u8d25\u3001\u89e6\u53d1\u5668\u8bed\u6cd5\u9519\u8bef\u7b49\u3002\u901a\u8fc7\u67e5\u770b\u9519\u8bef\u4fe1\u606f\u3001\u4fee\u6539 SQL \u8bed\u53e5\u548c\u53cd\u590d\u6d4b\u8bd5\uff0c\u6700\u7ec8\u89e3\u51b3\u4e86\u8fd9\u4e9b\u95ee\u9898\u3002
\u200b
\u901a\u8fc7\u672c\u6b21\u5b9e\u9a8c\uff0c\u6211\u4e0d\u4ec5\u5de9\u56fa\u4e86\u6570\u636e\u5e93\u7406\u8bba\u77e5\u8bc6\uff0c\u4e5f\u63d0\u9ad8\u4e86 SQL \u7f16\u5199\u80fd\u529b\u548c\u6570\u636e\u5e93\u8c03\u8bd5\u80fd\u529b\u3002\u4eca\u540e\u5728\u8bbe\u8ba1\u6570\u636e\u5e93\u7cfb\u7edf<\/pre>\n","protected":false},"excerpt":{"rendered":"\u6570\u636e\u5e93\u7efc\u5408\u5b9e\u9a8c 1.\u9700\u6c42\u5206\u6790 \u67d0\u5927\u578b\u56fe\u4e66\u9986\u9700\u8981\u5f00\u53d1\u4e00\u5957\u6570\u5b57\u5316\u501f\u9605\u7ba1\u7406\u7cfb\u7edf\uff0c\u4e3b\u8981\u4e1a\u52a1\u9700\u6c42\u5982\u4e0b\uff1a \u56fe\u4e66\u4fe1\u606f\uff1a\u8bb0\u5f55\u56fe […]<\/p>\n","protected":false},"author":1,"featured_media":448,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[9],"tags":[],"class_list":["post-446","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-wenzhang"],"_links":{"self":[{"href":"https:\/\/fg2025.cn\/index.php\/wp-json\/wp\/v2\/posts\/446","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/fg2025.cn\/index.php\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/fg2025.cn\/index.php\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/fg2025.cn\/index.php\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/fg2025.cn\/index.php\/wp-json\/wp\/v2\/comments?post=446"}],"version-history":[{"count":0,"href":"https:\/\/fg2025.cn\/index.php\/wp-json\/wp\/v2\/posts\/446\/revisions"}],"wp:attachment":[{"href":"https:\/\/fg2025.cn\/index.php\/wp-json\/wp\/v2\/media?parent=446"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/fg2025.cn\/index.php\/wp-json\/wp\/v2\/categories?post=446"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/fg2025.cn\/index.php\/wp-json\/wp\/v2\/tags?post=446"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}
CREATE USER 'lib_user1'@'localhost'
IDENTIFIED BY '123456';
GRANT SELECT
ON library_db.book
TO 'lib_user1'@'localhost';
\u67e5\u770b\u6743\u9650\uff1a
SHOW GRANTS FOR 'lib_user1'@'localhost';
2.\u6388\u4e88\u6743\u9650\u5e76\u5141\u8bb8\u8f6c\u6388\u6743
GRANT SELECT, INSERT
ON library_db.reader
TO 'lib_user1'@'localhost'
WITH GRANT OPTION;
\u8bf4\u660e\uff1a
WITH GRANT OPTION \u8868\u793a\u8be5\u7528\u6237\u53ef\u4ee5\u5c06\u81ea\u5df1\u62e5\u6709\u7684\u6743\u9650\u518d\u6388\u4e88\u5176\u4ed6\u7528\u6237\u3002
3.\u56de\u6536\u6743\u9650
REVOKE INSERT
ON library_db.reader
FROM 'lib_user1'@'localhost';
4.\u521b\u5efa\u89d2\u8272\u5e76\u6388\u6743
CREATE ROLE 'reader_role';
GRANT SELECT
ON library_db.*
TO 'reader_role';
CREATE USER 'lib_user2'@'localhost'
IDENTIFIED BY '123456';
GRANT 'reader_role'
TO 'lib_user2'@'localhost';
SET DEFAULT ROLE 'reader_role'
TO 'lib_user2'@'localhost';<\/pre>\n\n\n\n
16.\u89c6\u56fe\u4e0e\u6d3e\u751f\u8868<\/h2>\n\n\n\n1.\u5e26\u805a\u5408\u51fd\u6570\u7684\u89c6\u56fe\uff1a\u7edf\u8ba1\u6bcf\u4e2a\u8bfb\u8005\u501f\u9605\u6b21\u6570
CREATE VIEW v_reader_borrow_count AS
SELECT r.rno, r.rname, COUNT(br.borrowid) AS borrow_count
FROM reader r
LEFT JOIN borrow br
ON r.rno = br.rno
GROUP BY r.rno, r.rname;
\u67e5\u8be2\uff1a
SELECT * FROM v_reader_borrow_count;
2.\u6d3e\u751f\u8868\uff1a\u67e5\u8be2\u501f\u9605\u6b21\u6570\u5927\u4e8e1\u7684\u8bfb\u8005
SELECT *
FROM (
SELECT rno, COUNT(*) AS borrow_count
FROM borrow
GROUP BY rno
) AS t
WHERE t.borrow_count > 1;
3.WITH \u5b50\u53e5\u7edf\u8ba1\u6bcf\u4f4d\u8bfb\u8005\u501f\u9605\u6570\u91cf
WITH reader_count AS (
SELECT rno, COUNT(*) AS total
FROM borrow
GROUP BY rno
)
SELECT r.rno, r.rname, rc.total
FROM reader r
LEFT JOIN reader_count rc
ON r.rno = rc.rno;
4.WITH \u5b50\u53e5\uff1a\u67e5\u8be2\u672a\u5f52\u8fd8\u56fe\u4e66
WITH unreturned AS (
SELECT br.borrowid, r.rname, b.bname,
br.borrowdate, br.returndate
FROM borrow br
JOIN reader r ON br.rno = r.rno
JOIN book b ON br.bno = b.bno
WHERE br.actualdate IS NULL
)
SELECT * FROM unreturned;<\/pre>\n\n\n\n17.\u6269\u5c55\u601d\u8003<\/h2>\n\n\n\n\n- \u5982\u4f55\u5904\u7406\u5206\u7c7b\u5b9e\u4f53\u7684\u81ea\u5173\u8054\uff1f<\/li>\n<\/ol>\n\n\n\n
\u5206\u7c7b\u5b9e\u4f53\u5b58\u5728\u201c\u4e0a\u7ea7\u5206\u7c7b\u201d\u548c\u201c\u4e0b\u7ea7\u5206\u7c7b\u201d\u7684\u5173\u7cfb\uff0c\u56e0\u6b64\u53ef\u4ee5\u5728 category \u8868\u4e2d\u8bbe\u7f6e parentid \u5b57\u6bb5\u3002
category(
cid,
cname,
parentid
)
\u5176\u4e2d cid \u662f\u5206\u7c7b\u7f16\u53f7\uff0cparentid \u662f\u4e0a\u7ea7\u5206\u7c7b\u7f16\u53f7\uff0c\u540c\u65f6 parentid \u4e5f\u662f\u6307\u5411 category.cid \u7684\u5916\u952e\u3002
\u5982\u679c\u67d0\u5206\u7c7b\u6ca1\u6709\u4e0a\u7ea7\u5206\u7c7b\uff0c\u5219 parentid \u53ef\u4ee5\u4e3a\u7a7a\u3002
\u8fd9\u79cd\u8bbe\u8ba1\u53ef\u4ee5\u8868\u793a\u6811\u5f62\u7ed3\u6784\uff0c\u4f8b\u5982\uff1a
\u56fe\u4e66
\u251c\u2500\u2500 \u8ba1\u7b97\u673a
\u2502 \u251c\u2500\u2500 \u6570\u636e\u5e93
\u2502 \u2514\u2500\u2500 \u7f51\u7edc\u6280\u672f
\u2514\u2500\u2500 \u6587\u5b66
\u2514\u2500\u2500 \u79d1\u5e7b\u5c0f\u8bf4<\/pre>\n\n\n\n
\n\n\n\n2. \u501f\u9605\u5173\u7cfb\u662f\u5426\u53ef\u80fd\u5b58\u5728\u6570\u636e\u5197\u4f59\uff1f<\/h2>\n\n\n\n\u501f\u9605\u8868\u5982\u679c\u53ea\u4fdd\u5b58 rno\u3001bno\u3001borrowdate\u3001returndate\u3001actualdate \u7b49\u4fe1\u606f\uff0c\u5219\u5197\u4f59\u8f83\u5c11\u3002
\u4f46\u662f\u5982\u679c\u5728 borrow \u8868\u4e2d\u540c\u65f6\u4fdd\u5b58\u8bfb\u8005\u59d3\u540d rname\u3001\u56fe\u4e66\u540d\u79f0 bname\u3001\u51fa\u7248\u793e press \u7b49\u4fe1\u606f\uff0c\u5c31\u4f1a\u4ea7\u751f\u6570\u636e\u5197\u4f59\u3002
\u4f8b\u5982\uff1a
borrow(borrowid, rno, rname, bno, bname, borrowdate)
\u5176\u4e2d rname \u4f9d\u8d56 rno\uff0cbname \u4f9d\u8d56 bno\uff0c\u800c\u4e0d\u662f\u76f4\u63a5\u4f9d\u8d56 borrowid\uff0c\u4f1a\u4ea7\u751f\u4f20\u9012\u4f9d\u8d56\u3002
\u89c4\u8303\u5316\u65b9\u6848\uff1a
\u5c06\u8bfb\u8005\u4fe1\u606f\u4fdd\u5b58\u5728 reader \u8868\uff1b
\u5c06\u56fe\u4e66\u4fe1\u606f\u4fdd\u5b58\u5728 book \u8868\uff1b
borrow \u8868\u53ea\u4fdd\u5b58\u8bfb\u8005\u8bc1\u53f7\u548c\u56fe\u4e66\u7f16\u53f7\u4f5c\u4e3a\u5916\u952e\u3002<\/pre>\n\n\n\n
\n\n\n\n3. \u5982\u4f55\u9632\u6b62\u5e93\u5b58\u4e3a\u8d1f\u6570\uff1f<\/h2>\n\n\n\n\u53ef\u4ee5\u4ece\u4e24\u4e2a\u65b9\u9762\u9632\u6b62\u5e93\u5b58\u4e3a\u8d1f\u6570\uff1a
\u7b2c\u4e00\uff0c\u5728 book \u8868\u4e2d\u8bbe\u7f6e CHECK(stock >= 0) \u7ea6\u675f\uff0c\u4fdd\u8bc1\u5e93\u5b58\u4e0d\u80fd\u5c0f\u4e8e0\u3002
\u7b2c\u4e8c\uff0c\u5728\u501f\u4e66\u89e6\u53d1\u5668\u4e2d\u5224\u65ad\u5e93\u5b58\u6570\u91cf\u3002
\u5f53\u63d2\u5165 borrow \u501f\u9605\u8bb0\u5f55\u65f6\uff0c\u5148\u67e5\u8be2\u56fe\u4e66\u5e93\u5b58\u3002
\u5982\u679c\u5e93\u5b58\u5c0f\u4e8e\u7b49\u4e8e0\uff0c\u5219\u4f7f\u7528 SIGNAL \u629b\u51fa\u9519\u8bef\uff0c\u963b\u6b62\u501f\u4e66\u64cd\u4f5c\uff1b
\u5982\u679c\u5e93\u5b58\u5927\u4e8e0\uff0c\u5219\u5141\u8bb8\u501f\u9605\uff0c\u5e76\u81ea\u52a8\u5c06\u5e93\u5b58\u51cf1\u3002
\u8fd9\u6837\u53ef\u4ee5\u4fdd\u8bc1\u501f\u4e66\u65f6\u4e0d\u4f1a\u51fa\u73b0\u5e93\u5b58\u4e3a\u8d1f\u6570\u7684\u60c5\u51b5\u3002<\/pre>\n\n\n\n
\n\n\n\n4. \u9884\u7ea6\u56fe\u4e66\u529f\u80fd\u9700\u8981\u589e\u52a0\u54ea\u4e9b\u5b9e\u4f53\u548c\u5173\u7cfb\uff1f<\/h2>\n\n\n\n\u5982\u679c\u7cfb\u7edf\u652f\u6301\u9884\u7ea6\u56fe\u4e66\u529f\u80fd\uff0c\u53ef\u4ee5\u589e\u52a0 reservation \u9884\u7ea6\u8868\u3002
reservation(
reserveid,
rno,
bno,
reservedate,
status
)
\u5176\u4e2d\uff1a
reserveid \u8868\u793a\u9884\u7ea6\u7f16\u53f7\uff1b
rno \u662f\u8bfb\u8005\u8bc1\u53f7\uff0c\u5916\u952e\u5f15\u7528 reader.rno\uff1b
bno \u662f\u56fe\u4e66\u7f16\u53f7\uff0c\u5916\u952e\u5f15\u7528 book.bno\uff1b
reservedate \u8868\u793a\u9884\u7ea6\u65e5\u671f\uff1b
status \u8868\u793a\u9884\u7ea6\u72b6\u6001\uff0c\u5982\u201c\u9884\u7ea6\u4e2d\u201d\u201c\u5df2\u53d6\u6d88\u201d\u201c\u5df2\u5b8c\u6210\u201d\u3002
\u65b0\u589e\u5173\u7cfb\uff1a
\u4e00\u4e2a\u8bfb\u8005\u53ef\u4ee5\u9884\u7ea6\u591a\u672c\u56fe\u4e66\uff1b
\u4e00\u672c\u56fe\u4e66\u53ef\u4ee5\u88ab\u591a\u4e2a\u8bfb\u8005\u9884\u7ea6\uff1b
\u8bfb\u8005\u548c\u56fe\u4e66\u4e4b\u95f4\u901a\u8fc7 reservation \u8868\u5f62\u6210 m:n \u8054\u7cfb\u3002<\/pre>\n\n\n\n
\n\n\n\n5. \u4e3a\u4ec0\u4e48\u9075\u5faa\u6700\u5c0f\u6743\u9650\u539f\u5219\uff1f<\/h2>\n\n\n\n\u6700\u5c0f\u6743\u9650\u539f\u5219\u662f\u6307\u53ea\u7ed9\u7528\u6237\u5b8c\u6210\u5de5\u4f5c\u6240\u5fc5\u9700\u7684\u6743\u9650\uff0c\u4e0d\u6388\u4e88\u591a\u4f59\u6743\u9650\u3002
\u5728\u672c\u5b9e\u9a8c\u4e2d\uff0c\u5982\u679c\u67d0\u7528\u6237\u53ea\u8d1f\u8d23\u67e5\u8be2\u56fe\u4e66\u4fe1\u606f\uff0c\u5219\u53ea\u6388\u4e88 SELECT \u6743\u9650\u5373\u53ef\uff0c\u4e0d\u5e94\u8be5\u6388\u4e88 INSERT\u3001UPDATE\u3001DELETE \u7b49\u6743\u9650\u3002
\u4f8b\u5982\uff1a
GRANT SELECT ON library_db.book TO 'lib_user1'@'localhost';
\u8fd9\u6837\u53ef\u4ee5\u9632\u6b62\u7528\u6237\u8bef\u5220\u3001\u8bef\u6539\u6570\u636e\uff0c\u63d0\u9ad8\u6570\u636e\u5e93\u5b89\u5168\u6027\u3002
\u5982\u679c\u540e\u7eed\u4e0d\u518d\u9700\u8981\u67d0\u9879\u6743\u9650\uff0c\u8fd8\u53ef\u4ee5\u4f7f\u7528 REVOKE \u56de\u6536\u6743\u9650\u3002<\/pre>\n\n\n\n
\n\n\n\n6. \u5e76\u53d1\u501f\u9605\u5e93\u5b58\u4ec5\u52691\u672c\u7684\u56fe\u4e66\u4f1a\u4ea7\u751f\u4ec0\u4e48\u95ee\u9898\uff1f\u5982\u4f55\u89e3\u51b3\uff1f<\/h2>\n\n\n\n\u5f53\u591a\u7528\u6237\u540c\u65f6\u501f\u9605\u540c\u4e00\u672c\u5e93\u5b58\u4ec5\u52691\u672c\u7684\u56fe\u4e66\u65f6\uff0c\u53ef\u80fd\u51fa\u73b0\u8d85\u5356\u95ee\u9898\u3002
\u4f8b\u5982\u4e24\u4e2a\u7528\u6237\u540c\u65f6\u8bfb\u53d6\u5e93\u5b58 stock=1\uff0c\u90fd\u8ba4\u4e3a\u53ef\u4ee5\u501f\u9605\uff0c\u7136\u540e\u540c\u65f6\u63d2\u5165\u501f\u9605\u8bb0\u5f55\u5e76\u6267\u884c\u5e93\u5b58\u51cf1\uff0c\u6700\u7ec8\u53ef\u80fd\u5bfc\u81f4\u5e93\u5b58\u5f02\u5e38\u6216\u51fa\u73b0\u8d85\u989d\u501f\u9605\u3002
\u89e3\u51b3\u65b9\u6cd5\uff1a
1. \u4f7f\u7528\u4e8b\u52a1\u4fdd\u8bc1\u501f\u4e66\u64cd\u4f5c\u7684\u539f\u5b50\u6027\uff1b
2. \u4f7f\u7528 SELECT ... FOR UPDATE \u5bf9\u56fe\u4e66\u5e93\u5b58\u8bb0\u5f55\u52a0\u884c\u7ea7\u9501\uff1b
3. \u5728\u89e6\u53d1\u5668\u4e2d\u5224\u65ad\u5e93\u5b58\u662f\u5426\u5927\u4e8e0\uff1b
4. \u7ed9 stock \u5b57\u6bb5\u8bbe\u7f6e CHECK(stock >= 0) \u7ea6\u675f\u3002
\u793a\u4f8b\uff1a
START TRANSACTION;
SELECT stock
FROM book
WHERE bno='B001'
FOR UPDATE;
UPDATE book
SET stock = stock - 1
WHERE bno='B001'
AND stock > 0;
INSERT INTO borrow(rno,bno,borrowdate,returndate)
VALUES('R2024001','B001','2025-05-01','2025-05-15');
COMMIT;
\u8fd9\u6837\u53ef\u4ee5\u907f\u514d\u591a\u4e2a\u7528\u6237\u540c\u65f6\u4fee\u6539\u5e93\u5b58\u5bfc\u81f4\u6570\u636e\u4e0d\u4e00\u81f4\u3002<\/pre>\n\n\n\n
\n\n\n\n\u5b9e\u9a8c\u603b\u7ed3<\/h1>\n\n\n\n \u901a\u8fc7\u672c\u6b21\u56fe\u4e66\u501f\u9605\u7ba1\u7406\u7cfb\u7edf\u7efc\u5408\u5b9e\u9a8c\uff0c\u6211\u7cfb\u7edf\u5730\u5b8c\u6210\u4e86\u6570\u636e\u5e93\u8bbe\u8ba1\u4e0e\u5b9e\u73b0\u7684\u5168\u8fc7\u7a0b\u3002\u5b9e\u9a8c\u4ece\u9700\u6c42\u5206\u6790\u5f00\u59cb\uff0c\u9010\u6b65\u5b8c\u6210 E-R \u56fe\u8bbe\u8ba1\u3001\u5173\u7cfb\u6a21\u5f0f\u8f6c\u6362\u3001\u7269\u7406\u8868\u7ed3\u6784\u8bbe\u8ba1\u3001\u6570\u636e\u63d2\u5165\u3001\u67e5\u8be2\u64cd\u4f5c\u3001\u89c6\u56fe\u3001\u7d22\u5f15\u3001\u5b8c\u6574\u6027\u7ea6\u675f\u3001\u89e6\u53d1\u5668\u548c\u6743\u9650\u7ba1\u7406\u7b49\u5185\u5bb9\uff0c\u4f7f\u6211\u5bf9\u6570\u636e\u5e93\u5e94\u7528\u7cfb\u7edf\u7684\u8bbe\u8ba1\u6d41\u7a0b\u6709\u4e86\u66f4\u52a0\u5b8c\u6574\u7684\u8ba4\u8bc6\u3002
\u200b
\u5728\u5b9e\u9a8c\u8fc7\u7a0b\u4e2d\uff0c\u6211\u9996\u5148\u6839\u636e\u56fe\u4e66\u9986\u4e1a\u52a1\u9700\u6c42\u5206\u6790\u51fa\u56fe\u4e66\u3001\u8bfb\u8005\u3001\u501f\u9605\u3001\u51fa\u7248\u793e\u3001\u5206\u7c7b\u7b49\u5b9e\u4f53\uff0c\u5e76\u660e\u786e\u4e86\u5b83\u4eec\u4e4b\u95f4\u7684\u8054\u7cfb\u7c7b\u578b\u3002\u4f8b\u5982\uff0c\u51fa\u7248\u793e\u4e0e\u56fe\u4e66\u4e4b\u95f4\u662f\u4e00\u5bf9\u591a\u5173\u7cfb\uff0c\u5206\u7c7b\u4e0e\u56fe\u4e66\u4e4b\u95f4\u662f\u4e00\u5bf9\u591a\u5173\u7cfb\uff0c\u8bfb\u8005\u4e0e\u56fe\u4e66\u4e4b\u95f4\u901a\u8fc7\u501f\u9605\u8868\u5f62\u6210\u591a\u5bf9\u591a\u5173\u7cfb\u3002\u901a\u8fc7 E-R \u56fe\u8bbe\u8ba1\uff0c\u6211\u8fdb\u4e00\u6b65\u7406\u89e3\u4e86\u6982\u5ff5\u7ed3\u6784\u8bbe\u8ba1\u5728\u6570\u636e\u5e93\u5f00\u53d1\u4e2d\u7684\u91cd\u8981\u4f5c\u7528\u3002
\u200b
\u5728\u903b\u8f91\u7ed3\u6784\u8bbe\u8ba1\u9636\u6bb5\uff0c\u6211\u5c06 E-R \u56fe\u8f6c\u6362\u4e3a\u5173\u7cfb\u6a21\u5f0f\uff0c\u5e76\u5206\u6790\u5404\u8868\u662f\u5426\u6ee1\u8db3\u7b2c\u4e09\u8303\u5f0f\u3002\u901a\u8fc7\u89c4\u8303\u5316\u8bbe\u8ba1\uff0c\u907f\u514d\u4e86\u5728\u501f\u9605\u8868\u4e2d\u91cd\u590d\u4fdd\u5b58\u8bfb\u8005\u59d3\u540d\u3001\u56fe\u4e66\u540d\u79f0\u7b49\u4fe1\u606f\uff0c\u51cf\u5c11\u4e86\u6570\u636e\u5197\u4f59\uff0c\u63d0\u9ad8\u4e86\u6570\u636e\u4e00\u81f4\u6027\u3002\u5728\u7269\u7406\u8bbe\u8ba1\u9636\u6bb5\uff0c\u6211\u4f7f\u7528 SQL \u521b\u5efa\u6570\u636e\u5e93\u548c\u6570\u636e\u8868\uff0c\u8bbe\u7f6e\u4e86\u4e3b\u952e\u3001\u5916\u952e\u3001\u975e\u7a7a\u3001\u9ed8\u8ba4\u503c\u548c CHECK \u7ea6\u675f\uff0c\u5bf9\u5b9e\u4f53\u5b8c\u6574\u6027\u3001\u53c2\u7167\u5b8c\u6574\u6027\u548c\u7528\u6237\u5b9a\u4e49\u5b8c\u6574\u6027\u6709\u4e86\u66f4\u6df1\u523b\u7684\u7406\u89e3\u3002
\u200b
\u5728\u6570\u636e\u64cd\u4f5c\u90e8\u5206\uff0c\u6211\u7ec3\u4e60\u4e86 INSERT\u3001UPDATE\u3001DELETE \u548c SELECT \u8bed\u53e5\uff0c\u5e76\u5b8c\u6210\u4e86\u57fa\u7840\u67e5\u8be2\u3001\u805a\u5408\u67e5\u8be2\u3001\u591a\u8868\u8fde\u63a5\u67e5\u8be2\u3001\u5d4c\u5957\u67e5\u8be2\u548c\u96c6\u5408\u67e5\u8be2\u7b49\u5185\u5bb9\u3002\u901a\u8fc7\u8fd9\u4e9b\u7ec3\u4e60\uff0c\u6211\u638c\u63e1\u4e86 SQL \u67e5\u8be2\u8bed\u53e5\u7684\u5e38\u89c1\u5199\u6cd5\uff0c\u5c24\u5176\u662f\u591a\u8868\u8fde\u63a5\u548c\u5d4c\u5957\u67e5\u8be2\u7684\u4f7f\u7528\u65b9\u6cd5\u3002\u5b9e\u9a8c\u4e2d\u8fd8\u521b\u5efa\u4e86\u89c6\u56fe\u548c\u7d22\u5f15\uff0c\u7406\u89e3\u4e86\u89c6\u56fe\u53ef\u4ee5\u7b80\u5316\u590d\u6742\u67e5\u8be2\uff0c\u7d22\u5f15\u53ef\u4ee5\u63d0\u9ad8\u67e5\u8be2\u6548\u7387\uff0c\u4f46\u4e5f\u4f1a\u589e\u52a0\u7ef4\u62a4\u6210\u672c\u3002
\u200b
\u5728\u89e6\u53d1\u5668\u90e8\u5206\uff0c\u6211\u5b9e\u73b0\u4e86\u501f\u4e66\u81ea\u52a8\u51cf\u5c11\u5e93\u5b58\u3001\u8fd8\u4e66\u81ea\u52a8\u589e\u52a0\u5e93\u5b58\u5e76\u8ba1\u7b97\u7f5a\u6b3e\u3001\u5220\u9664\u8bfb\u8005\u524d\u8bb0\u5f55\u65e5\u5fd7\u7b49\u529f\u80fd\u3002\u901a\u8fc7\u89e6\u53d1\u5668\u5b9e\u9a8c\uff0c\u6211\u8ba4\u8bc6\u5230\u6570\u636e\u5e93\u4e0d\u4ec5\u53ef\u4ee5\u5b58\u50a8\u6570\u636e\uff0c\u8fd8\u53ef\u4ee5\u5728\u7279\u5b9a\u64cd\u4f5c\u53d1\u751f\u65f6\u81ea\u52a8\u6267\u884c\u4e00\u4e9b\u4e1a\u52a1\u903b\u8f91\u3002\u5b9e\u9a8c\u8fc7\u7a0b\u4e2d\u4e5f\u9047\u5230\u4e86\u4e00\u4e9b\u95ee\u9898\uff0c\u4f8b\u5982\u5916\u952e\u7ea6\u675f\u5bfc\u81f4\u6570\u636e\u65e0\u6cd5\u5220\u9664\u3001CHECK \u7ea6\u675f\u63d2\u5165\u5931\u8d25\u3001\u89e6\u53d1\u5668\u8bed\u6cd5\u9519\u8bef\u7b49\u3002\u901a\u8fc7\u67e5\u770b\u9519\u8bef\u4fe1\u606f\u3001\u4fee\u6539 SQL \u8bed\u53e5\u548c\u53cd\u590d\u6d4b\u8bd5\uff0c\u6700\u7ec8\u89e3\u51b3\u4e86\u8fd9\u4e9b\u95ee\u9898\u3002
\u200b
\u901a\u8fc7\u672c\u6b21\u5b9e\u9a8c\uff0c\u6211\u4e0d\u4ec5\u5de9\u56fa\u4e86\u6570\u636e\u5e93\u7406\u8bba\u77e5\u8bc6\uff0c\u4e5f\u63d0\u9ad8\u4e86 SQL \u7f16\u5199\u80fd\u529b\u548c\u6570\u636e\u5e93\u8c03\u8bd5\u80fd\u529b\u3002\u4eca\u540e\u5728\u8bbe\u8ba1\u6570\u636e\u5e93\u7cfb\u7edf<\/pre>\n","protected":false},"excerpt":{"rendered":"\u6570\u636e\u5e93\u7efc\u5408\u5b9e\u9a8c 1.\u9700\u6c42\u5206\u6790 \u67d0\u5927\u578b\u56fe\u4e66\u9986\u9700\u8981\u5f00\u53d1\u4e00\u5957\u6570\u5b57\u5316\u501f\u9605\u7ba1\u7406\u7cfb\u7edf\uff0c\u4e3b\u8981\u4e1a\u52a1\u9700\u6c42\u5982\u4e0b\uff1a \u56fe\u4e66\u4fe1\u606f\uff1a\u8bb0\u5f55\u56fe […]<\/p>\n","protected":false},"author":1,"featured_media":448,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[9],"tags":[],"class_list":["post-446","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-wenzhang"],"_links":{"self":[{"href":"https:\/\/fg2025.cn\/index.php\/wp-json\/wp\/v2\/posts\/446","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/fg2025.cn\/index.php\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/fg2025.cn\/index.php\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/fg2025.cn\/index.php\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/fg2025.cn\/index.php\/wp-json\/wp\/v2\/comments?post=446"}],"version-history":[{"count":0,"href":"https:\/\/fg2025.cn\/index.php\/wp-json\/wp\/v2\/posts\/446\/revisions"}],"wp:attachment":[{"href":"https:\/\/fg2025.cn\/index.php\/wp-json\/wp\/v2\/media?parent=446"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/fg2025.cn\/index.php\/wp-json\/wp\/v2\/categories?post=446"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/fg2025.cn\/index.php\/wp-json\/wp\/v2\/tags?post=446"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}
CREATE VIEW v_reader_borrow_count AS
SELECT r.rno, r.rname, COUNT(br.borrowid) AS borrow_count
FROM reader r
LEFT JOIN borrow br
ON r.rno = br.rno
GROUP BY r.rno, r.rname;
\u67e5\u8be2\uff1a
SELECT * FROM v_reader_borrow_count;
2.\u6d3e\u751f\u8868\uff1a\u67e5\u8be2\u501f\u9605\u6b21\u6570\u5927\u4e8e1\u7684\u8bfb\u8005
SELECT *
FROM (
SELECT rno, COUNT(*) AS borrow_count
FROM borrow
GROUP BY rno
) AS t
WHERE t.borrow_count > 1;
3.WITH \u5b50\u53e5\u7edf\u8ba1\u6bcf\u4f4d\u8bfb\u8005\u501f\u9605\u6570\u91cf
WITH reader_count AS (
SELECT rno, COUNT(*) AS total
FROM borrow
GROUP BY rno
)
SELECT r.rno, r.rname, rc.total
FROM reader r
LEFT JOIN reader_count rc
ON r.rno = rc.rno;
4.WITH \u5b50\u53e5\uff1a\u67e5\u8be2\u672a\u5f52\u8fd8\u56fe\u4e66
WITH unreturned AS (
SELECT br.borrowid, r.rname, b.bname,
br.borrowdate, br.returndate
FROM borrow br
JOIN reader r ON br.rno = r.rno
JOIN book b ON br.bno = b.bno
WHERE br.actualdate IS NULL
)
SELECT * FROM unreturned;<\/pre>\n\n\n\n
17.\u6269\u5c55\u601d\u8003<\/h2>\n\n\n\n\n- \u5982\u4f55\u5904\u7406\u5206\u7c7b\u5b9e\u4f53\u7684\u81ea\u5173\u8054\uff1f<\/li>\n<\/ol>\n\n\n\n
\u5206\u7c7b\u5b9e\u4f53\u5b58\u5728\u201c\u4e0a\u7ea7\u5206\u7c7b\u201d\u548c\u201c\u4e0b\u7ea7\u5206\u7c7b\u201d\u7684\u5173\u7cfb\uff0c\u56e0\u6b64\u53ef\u4ee5\u5728 category \u8868\u4e2d\u8bbe\u7f6e parentid \u5b57\u6bb5\u3002
category(
cid,
cname,
parentid
)
\u5176\u4e2d cid \u662f\u5206\u7c7b\u7f16\u53f7\uff0cparentid \u662f\u4e0a\u7ea7\u5206\u7c7b\u7f16\u53f7\uff0c\u540c\u65f6 parentid \u4e5f\u662f\u6307\u5411 category.cid \u7684\u5916\u952e\u3002
\u5982\u679c\u67d0\u5206\u7c7b\u6ca1\u6709\u4e0a\u7ea7\u5206\u7c7b\uff0c\u5219 parentid \u53ef\u4ee5\u4e3a\u7a7a\u3002
\u8fd9\u79cd\u8bbe\u8ba1\u53ef\u4ee5\u8868\u793a\u6811\u5f62\u7ed3\u6784\uff0c\u4f8b\u5982\uff1a
\u56fe\u4e66
\u251c\u2500\u2500 \u8ba1\u7b97\u673a
\u2502 \u251c\u2500\u2500 \u6570\u636e\u5e93
\u2502 \u2514\u2500\u2500 \u7f51\u7edc\u6280\u672f
\u2514\u2500\u2500 \u6587\u5b66
\u2514\u2500\u2500 \u79d1\u5e7b\u5c0f\u8bf4<\/pre>\n\n\n\n
\n\n\n\n2. \u501f\u9605\u5173\u7cfb\u662f\u5426\u53ef\u80fd\u5b58\u5728\u6570\u636e\u5197\u4f59\uff1f<\/h2>\n\n\n\n\u501f\u9605\u8868\u5982\u679c\u53ea\u4fdd\u5b58 rno\u3001bno\u3001borrowdate\u3001returndate\u3001actualdate \u7b49\u4fe1\u606f\uff0c\u5219\u5197\u4f59\u8f83\u5c11\u3002
\u4f46\u662f\u5982\u679c\u5728 borrow \u8868\u4e2d\u540c\u65f6\u4fdd\u5b58\u8bfb\u8005\u59d3\u540d rname\u3001\u56fe\u4e66\u540d\u79f0 bname\u3001\u51fa\u7248\u793e press \u7b49\u4fe1\u606f\uff0c\u5c31\u4f1a\u4ea7\u751f\u6570\u636e\u5197\u4f59\u3002
\u4f8b\u5982\uff1a
borrow(borrowid, rno, rname, bno, bname, borrowdate)
\u5176\u4e2d rname \u4f9d\u8d56 rno\uff0cbname \u4f9d\u8d56 bno\uff0c\u800c\u4e0d\u662f\u76f4\u63a5\u4f9d\u8d56 borrowid\uff0c\u4f1a\u4ea7\u751f\u4f20\u9012\u4f9d\u8d56\u3002
\u89c4\u8303\u5316\u65b9\u6848\uff1a
\u5c06\u8bfb\u8005\u4fe1\u606f\u4fdd\u5b58\u5728 reader \u8868\uff1b
\u5c06\u56fe\u4e66\u4fe1\u606f\u4fdd\u5b58\u5728 book \u8868\uff1b
borrow \u8868\u53ea\u4fdd\u5b58\u8bfb\u8005\u8bc1\u53f7\u548c\u56fe\u4e66\u7f16\u53f7\u4f5c\u4e3a\u5916\u952e\u3002<\/pre>\n\n\n\n
\n\n\n\n3. \u5982\u4f55\u9632\u6b62\u5e93\u5b58\u4e3a\u8d1f\u6570\uff1f<\/h2>\n\n\n\n\u53ef\u4ee5\u4ece\u4e24\u4e2a\u65b9\u9762\u9632\u6b62\u5e93\u5b58\u4e3a\u8d1f\u6570\uff1a
\u7b2c\u4e00\uff0c\u5728 book \u8868\u4e2d\u8bbe\u7f6e CHECK(stock >= 0) \u7ea6\u675f\uff0c\u4fdd\u8bc1\u5e93\u5b58\u4e0d\u80fd\u5c0f\u4e8e0\u3002
\u7b2c\u4e8c\uff0c\u5728\u501f\u4e66\u89e6\u53d1\u5668\u4e2d\u5224\u65ad\u5e93\u5b58\u6570\u91cf\u3002
\u5f53\u63d2\u5165 borrow \u501f\u9605\u8bb0\u5f55\u65f6\uff0c\u5148\u67e5\u8be2\u56fe\u4e66\u5e93\u5b58\u3002
\u5982\u679c\u5e93\u5b58\u5c0f\u4e8e\u7b49\u4e8e0\uff0c\u5219\u4f7f\u7528 SIGNAL \u629b\u51fa\u9519\u8bef\uff0c\u963b\u6b62\u501f\u4e66\u64cd\u4f5c\uff1b
\u5982\u679c\u5e93\u5b58\u5927\u4e8e0\uff0c\u5219\u5141\u8bb8\u501f\u9605\uff0c\u5e76\u81ea\u52a8\u5c06\u5e93\u5b58\u51cf1\u3002
\u8fd9\u6837\u53ef\u4ee5\u4fdd\u8bc1\u501f\u4e66\u65f6\u4e0d\u4f1a\u51fa\u73b0\u5e93\u5b58\u4e3a\u8d1f\u6570\u7684\u60c5\u51b5\u3002<\/pre>\n\n\n\n
\n\n\n\n4. \u9884\u7ea6\u56fe\u4e66\u529f\u80fd\u9700\u8981\u589e\u52a0\u54ea\u4e9b\u5b9e\u4f53\u548c\u5173\u7cfb\uff1f<\/h2>\n\n\n\n\u5982\u679c\u7cfb\u7edf\u652f\u6301\u9884\u7ea6\u56fe\u4e66\u529f\u80fd\uff0c\u53ef\u4ee5\u589e\u52a0 reservation \u9884\u7ea6\u8868\u3002
reservation(
reserveid,
rno,
bno,
reservedate,
status
)
\u5176\u4e2d\uff1a
reserveid \u8868\u793a\u9884\u7ea6\u7f16\u53f7\uff1b
rno \u662f\u8bfb\u8005\u8bc1\u53f7\uff0c\u5916\u952e\u5f15\u7528 reader.rno\uff1b
bno \u662f\u56fe\u4e66\u7f16\u53f7\uff0c\u5916\u952e\u5f15\u7528 book.bno\uff1b
reservedate \u8868\u793a\u9884\u7ea6\u65e5\u671f\uff1b
status \u8868\u793a\u9884\u7ea6\u72b6\u6001\uff0c\u5982\u201c\u9884\u7ea6\u4e2d\u201d\u201c\u5df2\u53d6\u6d88\u201d\u201c\u5df2\u5b8c\u6210\u201d\u3002
\u65b0\u589e\u5173\u7cfb\uff1a
\u4e00\u4e2a\u8bfb\u8005\u53ef\u4ee5\u9884\u7ea6\u591a\u672c\u56fe\u4e66\uff1b
\u4e00\u672c\u56fe\u4e66\u53ef\u4ee5\u88ab\u591a\u4e2a\u8bfb\u8005\u9884\u7ea6\uff1b
\u8bfb\u8005\u548c\u56fe\u4e66\u4e4b\u95f4\u901a\u8fc7 reservation \u8868\u5f62\u6210 m:n \u8054\u7cfb\u3002<\/pre>\n\n\n\n
\n\n\n\n5. \u4e3a\u4ec0\u4e48\u9075\u5faa\u6700\u5c0f\u6743\u9650\u539f\u5219\uff1f<\/h2>\n\n\n\n\u6700\u5c0f\u6743\u9650\u539f\u5219\u662f\u6307\u53ea\u7ed9\u7528\u6237\u5b8c\u6210\u5de5\u4f5c\u6240\u5fc5\u9700\u7684\u6743\u9650\uff0c\u4e0d\u6388\u4e88\u591a\u4f59\u6743\u9650\u3002
\u5728\u672c\u5b9e\u9a8c\u4e2d\uff0c\u5982\u679c\u67d0\u7528\u6237\u53ea\u8d1f\u8d23\u67e5\u8be2\u56fe\u4e66\u4fe1\u606f\uff0c\u5219\u53ea\u6388\u4e88 SELECT \u6743\u9650\u5373\u53ef\uff0c\u4e0d\u5e94\u8be5\u6388\u4e88 INSERT\u3001UPDATE\u3001DELETE \u7b49\u6743\u9650\u3002
\u4f8b\u5982\uff1a
GRANT SELECT ON library_db.book TO 'lib_user1'@'localhost';
\u8fd9\u6837\u53ef\u4ee5\u9632\u6b62\u7528\u6237\u8bef\u5220\u3001\u8bef\u6539\u6570\u636e\uff0c\u63d0\u9ad8\u6570\u636e\u5e93\u5b89\u5168\u6027\u3002
\u5982\u679c\u540e\u7eed\u4e0d\u518d\u9700\u8981\u67d0\u9879\u6743\u9650\uff0c\u8fd8\u53ef\u4ee5\u4f7f\u7528 REVOKE \u56de\u6536\u6743\u9650\u3002<\/pre>\n\n\n\n
\n\n\n\n6. \u5e76\u53d1\u501f\u9605\u5e93\u5b58\u4ec5\u52691\u672c\u7684\u56fe\u4e66\u4f1a\u4ea7\u751f\u4ec0\u4e48\u95ee\u9898\uff1f\u5982\u4f55\u89e3\u51b3\uff1f<\/h2>\n\n\n\n\u5f53\u591a\u7528\u6237\u540c\u65f6\u501f\u9605\u540c\u4e00\u672c\u5e93\u5b58\u4ec5\u52691\u672c\u7684\u56fe\u4e66\u65f6\uff0c\u53ef\u80fd\u51fa\u73b0\u8d85\u5356\u95ee\u9898\u3002
\u4f8b\u5982\u4e24\u4e2a\u7528\u6237\u540c\u65f6\u8bfb\u53d6\u5e93\u5b58 stock=1\uff0c\u90fd\u8ba4\u4e3a\u53ef\u4ee5\u501f\u9605\uff0c\u7136\u540e\u540c\u65f6\u63d2\u5165\u501f\u9605\u8bb0\u5f55\u5e76\u6267\u884c\u5e93\u5b58\u51cf1\uff0c\u6700\u7ec8\u53ef\u80fd\u5bfc\u81f4\u5e93\u5b58\u5f02\u5e38\u6216\u51fa\u73b0\u8d85\u989d\u501f\u9605\u3002
\u89e3\u51b3\u65b9\u6cd5\uff1a
1. \u4f7f\u7528\u4e8b\u52a1\u4fdd\u8bc1\u501f\u4e66\u64cd\u4f5c\u7684\u539f\u5b50\u6027\uff1b
2. \u4f7f\u7528 SELECT ... FOR UPDATE \u5bf9\u56fe\u4e66\u5e93\u5b58\u8bb0\u5f55\u52a0\u884c\u7ea7\u9501\uff1b
3. \u5728\u89e6\u53d1\u5668\u4e2d\u5224\u65ad\u5e93\u5b58\u662f\u5426\u5927\u4e8e0\uff1b
4. \u7ed9 stock \u5b57\u6bb5\u8bbe\u7f6e CHECK(stock >= 0) \u7ea6\u675f\u3002
\u793a\u4f8b\uff1a
START TRANSACTION;
SELECT stock
FROM book
WHERE bno='B001'
FOR UPDATE;
UPDATE book
SET stock = stock - 1
WHERE bno='B001'
AND stock > 0;
INSERT INTO borrow(rno,bno,borrowdate,returndate)
VALUES('R2024001','B001','2025-05-01','2025-05-15');
COMMIT;
\u8fd9\u6837\u53ef\u4ee5\u907f\u514d\u591a\u4e2a\u7528\u6237\u540c\u65f6\u4fee\u6539\u5e93\u5b58\u5bfc\u81f4\u6570\u636e\u4e0d\u4e00\u81f4\u3002<\/pre>\n\n\n\n
\n\n\n\n\u5b9e\u9a8c\u603b\u7ed3<\/h1>\n\n\n\n \u901a\u8fc7\u672c\u6b21\u56fe\u4e66\u501f\u9605\u7ba1\u7406\u7cfb\u7edf\u7efc\u5408\u5b9e\u9a8c\uff0c\u6211\u7cfb\u7edf\u5730\u5b8c\u6210\u4e86\u6570\u636e\u5e93\u8bbe\u8ba1\u4e0e\u5b9e\u73b0\u7684\u5168\u8fc7\u7a0b\u3002\u5b9e\u9a8c\u4ece\u9700\u6c42\u5206\u6790\u5f00\u59cb\uff0c\u9010\u6b65\u5b8c\u6210 E-R \u56fe\u8bbe\u8ba1\u3001\u5173\u7cfb\u6a21\u5f0f\u8f6c\u6362\u3001\u7269\u7406\u8868\u7ed3\u6784\u8bbe\u8ba1\u3001\u6570\u636e\u63d2\u5165\u3001\u67e5\u8be2\u64cd\u4f5c\u3001\u89c6\u56fe\u3001\u7d22\u5f15\u3001\u5b8c\u6574\u6027\u7ea6\u675f\u3001\u89e6\u53d1\u5668\u548c\u6743\u9650\u7ba1\u7406\u7b49\u5185\u5bb9\uff0c\u4f7f\u6211\u5bf9\u6570\u636e\u5e93\u5e94\u7528\u7cfb\u7edf\u7684\u8bbe\u8ba1\u6d41\u7a0b\u6709\u4e86\u66f4\u52a0\u5b8c\u6574\u7684\u8ba4\u8bc6\u3002
\u200b
\u5728\u5b9e\u9a8c\u8fc7\u7a0b\u4e2d\uff0c\u6211\u9996\u5148\u6839\u636e\u56fe\u4e66\u9986\u4e1a\u52a1\u9700\u6c42\u5206\u6790\u51fa\u56fe\u4e66\u3001\u8bfb\u8005\u3001\u501f\u9605\u3001\u51fa\u7248\u793e\u3001\u5206\u7c7b\u7b49\u5b9e\u4f53\uff0c\u5e76\u660e\u786e\u4e86\u5b83\u4eec\u4e4b\u95f4\u7684\u8054\u7cfb\u7c7b\u578b\u3002\u4f8b\u5982\uff0c\u51fa\u7248\u793e\u4e0e\u56fe\u4e66\u4e4b\u95f4\u662f\u4e00\u5bf9\u591a\u5173\u7cfb\uff0c\u5206\u7c7b\u4e0e\u56fe\u4e66\u4e4b\u95f4\u662f\u4e00\u5bf9\u591a\u5173\u7cfb\uff0c\u8bfb\u8005\u4e0e\u56fe\u4e66\u4e4b\u95f4\u901a\u8fc7\u501f\u9605\u8868\u5f62\u6210\u591a\u5bf9\u591a\u5173\u7cfb\u3002\u901a\u8fc7 E-R \u56fe\u8bbe\u8ba1\uff0c\u6211\u8fdb\u4e00\u6b65\u7406\u89e3\u4e86\u6982\u5ff5\u7ed3\u6784\u8bbe\u8ba1\u5728\u6570\u636e\u5e93\u5f00\u53d1\u4e2d\u7684\u91cd\u8981\u4f5c\u7528\u3002
\u200b
\u5728\u903b\u8f91\u7ed3\u6784\u8bbe\u8ba1\u9636\u6bb5\uff0c\u6211\u5c06 E-R \u56fe\u8f6c\u6362\u4e3a\u5173\u7cfb\u6a21\u5f0f\uff0c\u5e76\u5206\u6790\u5404\u8868\u662f\u5426\u6ee1\u8db3\u7b2c\u4e09\u8303\u5f0f\u3002\u901a\u8fc7\u89c4\u8303\u5316\u8bbe\u8ba1\uff0c\u907f\u514d\u4e86\u5728\u501f\u9605\u8868\u4e2d\u91cd\u590d\u4fdd\u5b58\u8bfb\u8005\u59d3\u540d\u3001\u56fe\u4e66\u540d\u79f0\u7b49\u4fe1\u606f\uff0c\u51cf\u5c11\u4e86\u6570\u636e\u5197\u4f59\uff0c\u63d0\u9ad8\u4e86\u6570\u636e\u4e00\u81f4\u6027\u3002\u5728\u7269\u7406\u8bbe\u8ba1\u9636\u6bb5\uff0c\u6211\u4f7f\u7528 SQL \u521b\u5efa\u6570\u636e\u5e93\u548c\u6570\u636e\u8868\uff0c\u8bbe\u7f6e\u4e86\u4e3b\u952e\u3001\u5916\u952e\u3001\u975e\u7a7a\u3001\u9ed8\u8ba4\u503c\u548c CHECK \u7ea6\u675f\uff0c\u5bf9\u5b9e\u4f53\u5b8c\u6574\u6027\u3001\u53c2\u7167\u5b8c\u6574\u6027\u548c\u7528\u6237\u5b9a\u4e49\u5b8c\u6574\u6027\u6709\u4e86\u66f4\u6df1\u523b\u7684\u7406\u89e3\u3002
\u200b
\u5728\u6570\u636e\u64cd\u4f5c\u90e8\u5206\uff0c\u6211\u7ec3\u4e60\u4e86 INSERT\u3001UPDATE\u3001DELETE \u548c SELECT \u8bed\u53e5\uff0c\u5e76\u5b8c\u6210\u4e86\u57fa\u7840\u67e5\u8be2\u3001\u805a\u5408\u67e5\u8be2\u3001\u591a\u8868\u8fde\u63a5\u67e5\u8be2\u3001\u5d4c\u5957\u67e5\u8be2\u548c\u96c6\u5408\u67e5\u8be2\u7b49\u5185\u5bb9\u3002\u901a\u8fc7\u8fd9\u4e9b\u7ec3\u4e60\uff0c\u6211\u638c\u63e1\u4e86 SQL \u67e5\u8be2\u8bed\u53e5\u7684\u5e38\u89c1\u5199\u6cd5\uff0c\u5c24\u5176\u662f\u591a\u8868\u8fde\u63a5\u548c\u5d4c\u5957\u67e5\u8be2\u7684\u4f7f\u7528\u65b9\u6cd5\u3002\u5b9e\u9a8c\u4e2d\u8fd8\u521b\u5efa\u4e86\u89c6\u56fe\u548c\u7d22\u5f15\uff0c\u7406\u89e3\u4e86\u89c6\u56fe\u53ef\u4ee5\u7b80\u5316\u590d\u6742\u67e5\u8be2\uff0c\u7d22\u5f15\u53ef\u4ee5\u63d0\u9ad8\u67e5\u8be2\u6548\u7387\uff0c\u4f46\u4e5f\u4f1a\u589e\u52a0\u7ef4\u62a4\u6210\u672c\u3002
\u200b
\u5728\u89e6\u53d1\u5668\u90e8\u5206\uff0c\u6211\u5b9e\u73b0\u4e86\u501f\u4e66\u81ea\u52a8\u51cf\u5c11\u5e93\u5b58\u3001\u8fd8\u4e66\u81ea\u52a8\u589e\u52a0\u5e93\u5b58\u5e76\u8ba1\u7b97\u7f5a\u6b3e\u3001\u5220\u9664\u8bfb\u8005\u524d\u8bb0\u5f55\u65e5\u5fd7\u7b49\u529f\u80fd\u3002\u901a\u8fc7\u89e6\u53d1\u5668\u5b9e\u9a8c\uff0c\u6211\u8ba4\u8bc6\u5230\u6570\u636e\u5e93\u4e0d\u4ec5\u53ef\u4ee5\u5b58\u50a8\u6570\u636e\uff0c\u8fd8\u53ef\u4ee5\u5728\u7279\u5b9a\u64cd\u4f5c\u53d1\u751f\u65f6\u81ea\u52a8\u6267\u884c\u4e00\u4e9b\u4e1a\u52a1\u903b\u8f91\u3002\u5b9e\u9a8c\u8fc7\u7a0b\u4e2d\u4e5f\u9047\u5230\u4e86\u4e00\u4e9b\u95ee\u9898\uff0c\u4f8b\u5982\u5916\u952e\u7ea6\u675f\u5bfc\u81f4\u6570\u636e\u65e0\u6cd5\u5220\u9664\u3001CHECK \u7ea6\u675f\u63d2\u5165\u5931\u8d25\u3001\u89e6\u53d1\u5668\u8bed\u6cd5\u9519\u8bef\u7b49\u3002\u901a\u8fc7\u67e5\u770b\u9519\u8bef\u4fe1\u606f\u3001\u4fee\u6539 SQL \u8bed\u53e5\u548c\u53cd\u590d\u6d4b\u8bd5\uff0c\u6700\u7ec8\u89e3\u51b3\u4e86\u8fd9\u4e9b\u95ee\u9898\u3002
\u200b
\u901a\u8fc7\u672c\u6b21\u5b9e\u9a8c\uff0c\u6211\u4e0d\u4ec5\u5de9\u56fa\u4e86\u6570\u636e\u5e93\u7406\u8bba\u77e5\u8bc6\uff0c\u4e5f\u63d0\u9ad8\u4e86 SQL \u7f16\u5199\u80fd\u529b\u548c\u6570\u636e\u5e93\u8c03\u8bd5\u80fd\u529b\u3002\u4eca\u540e\u5728\u8bbe\u8ba1\u6570\u636e\u5e93\u7cfb\u7edf<\/pre>\n","protected":false},"excerpt":{"rendered":"\u6570\u636e\u5e93\u7efc\u5408\u5b9e\u9a8c 1.\u9700\u6c42\u5206\u6790 \u67d0\u5927\u578b\u56fe\u4e66\u9986\u9700\u8981\u5f00\u53d1\u4e00\u5957\u6570\u5b57\u5316\u501f\u9605\u7ba1\u7406\u7cfb\u7edf\uff0c\u4e3b\u8981\u4e1a\u52a1\u9700\u6c42\u5982\u4e0b\uff1a \u56fe\u4e66\u4fe1\u606f\uff1a\u8bb0\u5f55\u56fe […]<\/p>\n","protected":false},"author":1,"featured_media":448,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[9],"tags":[],"class_list":["post-446","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-wenzhang"],"_links":{"self":[{"href":"https:\/\/fg2025.cn\/index.php\/wp-json\/wp\/v2\/posts\/446","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/fg2025.cn\/index.php\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/fg2025.cn\/index.php\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/fg2025.cn\/index.php\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/fg2025.cn\/index.php\/wp-json\/wp\/v2\/comments?post=446"}],"version-history":[{"count":0,"href":"https:\/\/fg2025.cn\/index.php\/wp-json\/wp\/v2\/posts\/446\/revisions"}],"wp:attachment":[{"href":"https:\/\/fg2025.cn\/index.php\/wp-json\/wp\/v2\/media?parent=446"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/fg2025.cn\/index.php\/wp-json\/wp\/v2\/categories?post=446"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/fg2025.cn\/index.php\/wp-json\/wp\/v2\/tags?post=446"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}
\u5206\u7c7b\u5b9e\u4f53\u5b58\u5728\u201c\u4e0a\u7ea7\u5206\u7c7b\u201d\u548c\u201c\u4e0b\u7ea7\u5206\u7c7b\u201d\u7684\u5173\u7cfb\uff0c\u56e0\u6b64\u53ef\u4ee5\u5728 category \u8868\u4e2d\u8bbe\u7f6e parentid \u5b57\u6bb5\u3002
category(
cid,
cname,
parentid
)
\u5176\u4e2d cid \u662f\u5206\u7c7b\u7f16\u53f7\uff0cparentid \u662f\u4e0a\u7ea7\u5206\u7c7b\u7f16\u53f7\uff0c\u540c\u65f6 parentid \u4e5f\u662f\u6307\u5411 category.cid \u7684\u5916\u952e\u3002
\u5982\u679c\u67d0\u5206\u7c7b\u6ca1\u6709\u4e0a\u7ea7\u5206\u7c7b\uff0c\u5219 parentid \u53ef\u4ee5\u4e3a\u7a7a\u3002
\u8fd9\u79cd\u8bbe\u8ba1\u53ef\u4ee5\u8868\u793a\u6811\u5f62\u7ed3\u6784\uff0c\u4f8b\u5982\uff1a
\u56fe\u4e66
\u251c\u2500\u2500 \u8ba1\u7b97\u673a
\u2502 \u251c\u2500\u2500 \u6570\u636e\u5e93
\u2502 \u2514\u2500\u2500 \u7f51\u7edc\u6280\u672f
\u2514\u2500\u2500 \u6587\u5b66
\u2514\u2500\u2500 \u79d1\u5e7b\u5c0f\u8bf4<\/pre>\n\n\n\n
\n\n\n\n2. \u501f\u9605\u5173\u7cfb\u662f\u5426\u53ef\u80fd\u5b58\u5728\u6570\u636e\u5197\u4f59\uff1f<\/h2>\n\n\n\n
\u501f\u9605\u8868\u5982\u679c\u53ea\u4fdd\u5b58 rno\u3001bno\u3001borrowdate\u3001returndate\u3001actualdate \u7b49\u4fe1\u606f\uff0c\u5219\u5197\u4f59\u8f83\u5c11\u3002
\u4f46\u662f\u5982\u679c\u5728 borrow \u8868\u4e2d\u540c\u65f6\u4fdd\u5b58\u8bfb\u8005\u59d3\u540d rname\u3001\u56fe\u4e66\u540d\u79f0 bname\u3001\u51fa\u7248\u793e press \u7b49\u4fe1\u606f\uff0c\u5c31\u4f1a\u4ea7\u751f\u6570\u636e\u5197\u4f59\u3002
\u4f8b\u5982\uff1a
borrow(borrowid, rno, rname, bno, bname, borrowdate)
\u5176\u4e2d rname \u4f9d\u8d56 rno\uff0cbname \u4f9d\u8d56 bno\uff0c\u800c\u4e0d\u662f\u76f4\u63a5\u4f9d\u8d56 borrowid\uff0c\u4f1a\u4ea7\u751f\u4f20\u9012\u4f9d\u8d56\u3002
\u89c4\u8303\u5316\u65b9\u6848\uff1a
\u5c06\u8bfb\u8005\u4fe1\u606f\u4fdd\u5b58\u5728 reader \u8868\uff1b
\u5c06\u56fe\u4e66\u4fe1\u606f\u4fdd\u5b58\u5728 book \u8868\uff1b
borrow \u8868\u53ea\u4fdd\u5b58\u8bfb\u8005\u8bc1\u53f7\u548c\u56fe\u4e66\u7f16\u53f7\u4f5c\u4e3a\u5916\u952e\u3002<\/pre>\n\n\n\n
\n\n\n\n3. \u5982\u4f55\u9632\u6b62\u5e93\u5b58\u4e3a\u8d1f\u6570\uff1f<\/h2>\n\n\n\n
\u53ef\u4ee5\u4ece\u4e24\u4e2a\u65b9\u9762\u9632\u6b62\u5e93\u5b58\u4e3a\u8d1f\u6570\uff1a
\u7b2c\u4e00\uff0c\u5728 book \u8868\u4e2d\u8bbe\u7f6e CHECK(stock >= 0) \u7ea6\u675f\uff0c\u4fdd\u8bc1\u5e93\u5b58\u4e0d\u80fd\u5c0f\u4e8e0\u3002
\u7b2c\u4e8c\uff0c\u5728\u501f\u4e66\u89e6\u53d1\u5668\u4e2d\u5224\u65ad\u5e93\u5b58\u6570\u91cf\u3002
\u5f53\u63d2\u5165 borrow \u501f\u9605\u8bb0\u5f55\u65f6\uff0c\u5148\u67e5\u8be2\u56fe\u4e66\u5e93\u5b58\u3002
\u5982\u679c\u5e93\u5b58\u5c0f\u4e8e\u7b49\u4e8e0\uff0c\u5219\u4f7f\u7528 SIGNAL \u629b\u51fa\u9519\u8bef\uff0c\u963b\u6b62\u501f\u4e66\u64cd\u4f5c\uff1b
\u5982\u679c\u5e93\u5b58\u5927\u4e8e0\uff0c\u5219\u5141\u8bb8\u501f\u9605\uff0c\u5e76\u81ea\u52a8\u5c06\u5e93\u5b58\u51cf1\u3002
\u8fd9\u6837\u53ef\u4ee5\u4fdd\u8bc1\u501f\u4e66\u65f6\u4e0d\u4f1a\u51fa\u73b0\u5e93\u5b58\u4e3a\u8d1f\u6570\u7684\u60c5\u51b5\u3002<\/pre>\n\n\n\n
\n\n\n\n4. \u9884\u7ea6\u56fe\u4e66\u529f\u80fd\u9700\u8981\u589e\u52a0\u54ea\u4e9b\u5b9e\u4f53\u548c\u5173\u7cfb\uff1f<\/h2>\n\n\n\n
\u5982\u679c\u7cfb\u7edf\u652f\u6301\u9884\u7ea6\u56fe\u4e66\u529f\u80fd\uff0c\u53ef\u4ee5\u589e\u52a0 reservation \u9884\u7ea6\u8868\u3002
reservation(
reserveid,
rno,
bno,
reservedate,
status
)
\u5176\u4e2d\uff1a
reserveid \u8868\u793a\u9884\u7ea6\u7f16\u53f7\uff1b
rno \u662f\u8bfb\u8005\u8bc1\u53f7\uff0c\u5916\u952e\u5f15\u7528 reader.rno\uff1b
bno \u662f\u56fe\u4e66\u7f16\u53f7\uff0c\u5916\u952e\u5f15\u7528 book.bno\uff1b
reservedate \u8868\u793a\u9884\u7ea6\u65e5\u671f\uff1b
status \u8868\u793a\u9884\u7ea6\u72b6\u6001\uff0c\u5982\u201c\u9884\u7ea6\u4e2d\u201d\u201c\u5df2\u53d6\u6d88\u201d\u201c\u5df2\u5b8c\u6210\u201d\u3002
\u65b0\u589e\u5173\u7cfb\uff1a
\u4e00\u4e2a\u8bfb\u8005\u53ef\u4ee5\u9884\u7ea6\u591a\u672c\u56fe\u4e66\uff1b
\u4e00\u672c\u56fe\u4e66\u53ef\u4ee5\u88ab\u591a\u4e2a\u8bfb\u8005\u9884\u7ea6\uff1b
\u8bfb\u8005\u548c\u56fe\u4e66\u4e4b\u95f4\u901a\u8fc7 reservation \u8868\u5f62\u6210 m:n \u8054\u7cfb\u3002<\/pre>\n\n\n\n
\n\n\n\n5. \u4e3a\u4ec0\u4e48\u9075\u5faa\u6700\u5c0f\u6743\u9650\u539f\u5219\uff1f<\/h2>\n\n\n\n
\u6700\u5c0f\u6743\u9650\u539f\u5219\u662f\u6307\u53ea\u7ed9\u7528\u6237\u5b8c\u6210\u5de5\u4f5c\u6240\u5fc5\u9700\u7684\u6743\u9650\uff0c\u4e0d\u6388\u4e88\u591a\u4f59\u6743\u9650\u3002
\u5728\u672c\u5b9e\u9a8c\u4e2d\uff0c\u5982\u679c\u67d0\u7528\u6237\u53ea\u8d1f\u8d23\u67e5\u8be2\u56fe\u4e66\u4fe1\u606f\uff0c\u5219\u53ea\u6388\u4e88 SELECT \u6743\u9650\u5373\u53ef\uff0c\u4e0d\u5e94\u8be5\u6388\u4e88 INSERT\u3001UPDATE\u3001DELETE \u7b49\u6743\u9650\u3002
\u4f8b\u5982\uff1a
GRANT SELECT ON library_db.book TO 'lib_user1'@'localhost';
\u8fd9\u6837\u53ef\u4ee5\u9632\u6b62\u7528\u6237\u8bef\u5220\u3001\u8bef\u6539\u6570\u636e\uff0c\u63d0\u9ad8\u6570\u636e\u5e93\u5b89\u5168\u6027\u3002
\u5982\u679c\u540e\u7eed\u4e0d\u518d\u9700\u8981\u67d0\u9879\u6743\u9650\uff0c\u8fd8\u53ef\u4ee5\u4f7f\u7528 REVOKE \u56de\u6536\u6743\u9650\u3002<\/pre>\n\n\n\n
\n\n\n\n6. \u5e76\u53d1\u501f\u9605\u5e93\u5b58\u4ec5\u52691\u672c\u7684\u56fe\u4e66\u4f1a\u4ea7\u751f\u4ec0\u4e48\u95ee\u9898\uff1f\u5982\u4f55\u89e3\u51b3\uff1f<\/h2>\n\n\n\n
\u5f53\u591a\u7528\u6237\u540c\u65f6\u501f\u9605\u540c\u4e00\u672c\u5e93\u5b58\u4ec5\u52691\u672c\u7684\u56fe\u4e66\u65f6\uff0c\u53ef\u80fd\u51fa\u73b0\u8d85\u5356\u95ee\u9898\u3002
\u4f8b\u5982\u4e24\u4e2a\u7528\u6237\u540c\u65f6\u8bfb\u53d6\u5e93\u5b58 stock=1\uff0c\u90fd\u8ba4\u4e3a\u53ef\u4ee5\u501f\u9605\uff0c\u7136\u540e\u540c\u65f6\u63d2\u5165\u501f\u9605\u8bb0\u5f55\u5e76\u6267\u884c\u5e93\u5b58\u51cf1\uff0c\u6700\u7ec8\u53ef\u80fd\u5bfc\u81f4\u5e93\u5b58\u5f02\u5e38\u6216\u51fa\u73b0\u8d85\u989d\u501f\u9605\u3002
\u89e3\u51b3\u65b9\u6cd5\uff1a
1. \u4f7f\u7528\u4e8b\u52a1\u4fdd\u8bc1\u501f\u4e66\u64cd\u4f5c\u7684\u539f\u5b50\u6027\uff1b
2. \u4f7f\u7528 SELECT ... FOR UPDATE \u5bf9\u56fe\u4e66\u5e93\u5b58\u8bb0\u5f55\u52a0\u884c\u7ea7\u9501\uff1b
3. \u5728\u89e6\u53d1\u5668\u4e2d\u5224\u65ad\u5e93\u5b58\u662f\u5426\u5927\u4e8e0\uff1b
4. \u7ed9 stock \u5b57\u6bb5\u8bbe\u7f6e CHECK(stock >= 0) \u7ea6\u675f\u3002
\u793a\u4f8b\uff1a
START TRANSACTION;
SELECT stock
FROM book
WHERE bno='B001'
FOR UPDATE;
UPDATE book
SET stock = stock - 1
WHERE bno='B001'
AND stock > 0;
INSERT INTO borrow(rno,bno,borrowdate,returndate)
VALUES('R2024001','B001','2025-05-01','2025-05-15');
COMMIT;
\u8fd9\u6837\u53ef\u4ee5\u907f\u514d\u591a\u4e2a\u7528\u6237\u540c\u65f6\u4fee\u6539\u5e93\u5b58\u5bfc\u81f4\u6570\u636e\u4e0d\u4e00\u81f4\u3002<\/pre>\n\n\n\n
\n\n\n\n\u5b9e\u9a8c\u603b\u7ed3<\/h1>\n\n\n\n
\u901a\u8fc7\u672c\u6b21\u56fe\u4e66\u501f\u9605\u7ba1\u7406\u7cfb\u7edf\u7efc\u5408\u5b9e\u9a8c\uff0c\u6211\u7cfb\u7edf\u5730\u5b8c\u6210\u4e86\u6570\u636e\u5e93\u8bbe\u8ba1\u4e0e\u5b9e\u73b0\u7684\u5168\u8fc7\u7a0b\u3002\u5b9e\u9a8c\u4ece\u9700\u6c42\u5206\u6790\u5f00\u59cb\uff0c\u9010\u6b65\u5b8c\u6210 E-R \u56fe\u8bbe\u8ba1\u3001\u5173\u7cfb\u6a21\u5f0f\u8f6c\u6362\u3001\u7269\u7406\u8868\u7ed3\u6784\u8bbe\u8ba1\u3001\u6570\u636e\u63d2\u5165\u3001\u67e5\u8be2\u64cd\u4f5c\u3001\u89c6\u56fe\u3001\u7d22\u5f15\u3001\u5b8c\u6574\u6027\u7ea6\u675f\u3001\u89e6\u53d1\u5668\u548c\u6743\u9650\u7ba1\u7406\u7b49\u5185\u5bb9\uff0c\u4f7f\u6211\u5bf9\u6570\u636e\u5e93\u5e94\u7528\u7cfb\u7edf\u7684\u8bbe\u8ba1\u6d41\u7a0b\u6709\u4e86\u66f4\u52a0\u5b8c\u6574\u7684\u8ba4\u8bc6\u3002
\u200b
\u5728\u5b9e\u9a8c\u8fc7\u7a0b\u4e2d\uff0c\u6211\u9996\u5148\u6839\u636e\u56fe\u4e66\u9986\u4e1a\u52a1\u9700\u6c42\u5206\u6790\u51fa\u56fe\u4e66\u3001\u8bfb\u8005\u3001\u501f\u9605\u3001\u51fa\u7248\u793e\u3001\u5206\u7c7b\u7b49\u5b9e\u4f53\uff0c\u5e76\u660e\u786e\u4e86\u5b83\u4eec\u4e4b\u95f4\u7684\u8054\u7cfb\u7c7b\u578b\u3002\u4f8b\u5982\uff0c\u51fa\u7248\u793e\u4e0e\u56fe\u4e66\u4e4b\u95f4\u662f\u4e00\u5bf9\u591a\u5173\u7cfb\uff0c\u5206\u7c7b\u4e0e\u56fe\u4e66\u4e4b\u95f4\u662f\u4e00\u5bf9\u591a\u5173\u7cfb\uff0c\u8bfb\u8005\u4e0e\u56fe\u4e66\u4e4b\u95f4\u901a\u8fc7\u501f\u9605\u8868\u5f62\u6210\u591a\u5bf9\u591a\u5173\u7cfb\u3002\u901a\u8fc7 E-R \u56fe\u8bbe\u8ba1\uff0c\u6211\u8fdb\u4e00\u6b65\u7406\u89e3\u4e86\u6982\u5ff5\u7ed3\u6784\u8bbe\u8ba1\u5728\u6570\u636e\u5e93\u5f00\u53d1\u4e2d\u7684\u91cd\u8981\u4f5c\u7528\u3002
\u200b
\u5728\u903b\u8f91\u7ed3\u6784\u8bbe\u8ba1\u9636\u6bb5\uff0c\u6211\u5c06 E-R \u56fe\u8f6c\u6362\u4e3a\u5173\u7cfb\u6a21\u5f0f\uff0c\u5e76\u5206\u6790\u5404\u8868\u662f\u5426\u6ee1\u8db3\u7b2c\u4e09\u8303\u5f0f\u3002\u901a\u8fc7\u89c4\u8303\u5316\u8bbe\u8ba1\uff0c\u907f\u514d\u4e86\u5728\u501f\u9605\u8868\u4e2d\u91cd\u590d\u4fdd\u5b58\u8bfb\u8005\u59d3\u540d\u3001\u56fe\u4e66\u540d\u79f0\u7b49\u4fe1\u606f\uff0c\u51cf\u5c11\u4e86\u6570\u636e\u5197\u4f59\uff0c\u63d0\u9ad8\u4e86\u6570\u636e\u4e00\u81f4\u6027\u3002\u5728\u7269\u7406\u8bbe\u8ba1\u9636\u6bb5\uff0c\u6211\u4f7f\u7528 SQL \u521b\u5efa\u6570\u636e\u5e93\u548c\u6570\u636e\u8868\uff0c\u8bbe\u7f6e\u4e86\u4e3b\u952e\u3001\u5916\u952e\u3001\u975e\u7a7a\u3001\u9ed8\u8ba4\u503c\u548c CHECK \u7ea6\u675f\uff0c\u5bf9\u5b9e\u4f53\u5b8c\u6574\u6027\u3001\u53c2\u7167\u5b8c\u6574\u6027\u548c\u7528\u6237\u5b9a\u4e49\u5b8c\u6574\u6027\u6709\u4e86\u66f4\u6df1\u523b\u7684\u7406\u89e3\u3002
\u200b
\u5728\u6570\u636e\u64cd\u4f5c\u90e8\u5206\uff0c\u6211\u7ec3\u4e60\u4e86 INSERT\u3001UPDATE\u3001DELETE \u548c SELECT \u8bed\u53e5\uff0c\u5e76\u5b8c\u6210\u4e86\u57fa\u7840\u67e5\u8be2\u3001\u805a\u5408\u67e5\u8be2\u3001\u591a\u8868\u8fde\u63a5\u67e5\u8be2\u3001\u5d4c\u5957\u67e5\u8be2\u548c\u96c6\u5408\u67e5\u8be2\u7b49\u5185\u5bb9\u3002\u901a\u8fc7\u8fd9\u4e9b\u7ec3\u4e60\uff0c\u6211\u638c\u63e1\u4e86 SQL \u67e5\u8be2\u8bed\u53e5\u7684\u5e38\u89c1\u5199\u6cd5\uff0c\u5c24\u5176\u662f\u591a\u8868\u8fde\u63a5\u548c\u5d4c\u5957\u67e5\u8be2\u7684\u4f7f\u7528\u65b9\u6cd5\u3002\u5b9e\u9a8c\u4e2d\u8fd8\u521b\u5efa\u4e86\u89c6\u56fe\u548c\u7d22\u5f15\uff0c\u7406\u89e3\u4e86\u89c6\u56fe\u53ef\u4ee5\u7b80\u5316\u590d\u6742\u67e5\u8be2\uff0c\u7d22\u5f15\u53ef\u4ee5\u63d0\u9ad8\u67e5\u8be2\u6548\u7387\uff0c\u4f46\u4e5f\u4f1a\u589e\u52a0\u7ef4\u62a4\u6210\u672c\u3002
\u200b
\u5728\u89e6\u53d1\u5668\u90e8\u5206\uff0c\u6211\u5b9e\u73b0\u4e86\u501f\u4e66\u81ea\u52a8\u51cf\u5c11\u5e93\u5b58\u3001\u8fd8\u4e66\u81ea\u52a8\u589e\u52a0\u5e93\u5b58\u5e76\u8ba1\u7b97\u7f5a\u6b3e\u3001\u5220\u9664\u8bfb\u8005\u524d\u8bb0\u5f55\u65e5\u5fd7\u7b49\u529f\u80fd\u3002\u901a\u8fc7\u89e6\u53d1\u5668\u5b9e\u9a8c\uff0c\u6211\u8ba4\u8bc6\u5230\u6570\u636e\u5e93\u4e0d\u4ec5\u53ef\u4ee5\u5b58\u50a8\u6570\u636e\uff0c\u8fd8\u53ef\u4ee5\u5728\u7279\u5b9a\u64cd\u4f5c\u53d1\u751f\u65f6\u81ea\u52a8\u6267\u884c\u4e00\u4e9b\u4e1a\u52a1\u903b\u8f91\u3002\u5b9e\u9a8c\u8fc7\u7a0b\u4e2d\u4e5f\u9047\u5230\u4e86\u4e00\u4e9b\u95ee\u9898\uff0c\u4f8b\u5982\u5916\u952e\u7ea6\u675f\u5bfc\u81f4\u6570\u636e\u65e0\u6cd5\u5220\u9664\u3001CHECK \u7ea6\u675f\u63d2\u5165\u5931\u8d25\u3001\u89e6\u53d1\u5668\u8bed\u6cd5\u9519\u8bef\u7b49\u3002\u901a\u8fc7\u67e5\u770b\u9519\u8bef\u4fe1\u606f\u3001\u4fee\u6539 SQL \u8bed\u53e5\u548c\u53cd\u590d\u6d4b\u8bd5\uff0c\u6700\u7ec8\u89e3\u51b3\u4e86\u8fd9\u4e9b\u95ee\u9898\u3002
\u200b
\u901a\u8fc7\u672c\u6b21\u5b9e\u9a8c\uff0c\u6211\u4e0d\u4ec5\u5de9\u56fa\u4e86\u6570\u636e\u5e93\u7406\u8bba\u77e5\u8bc6\uff0c\u4e5f\u63d0\u9ad8\u4e86 SQL \u7f16\u5199\u80fd\u529b\u548c\u6570\u636e\u5e93\u8c03\u8bd5\u80fd\u529b\u3002\u4eca\u540e\u5728\u8bbe\u8ba1\u6570\u636e\u5e93\u7cfb\u7edf<\/pre>\n","protected":false},"excerpt":{"rendered":"\u6570\u636e\u5e93\u7efc\u5408\u5b9e\u9a8c 1.\u9700\u6c42\u5206\u6790 \u67d0\u5927\u578b\u56fe\u4e66\u9986\u9700\u8981\u5f00\u53d1\u4e00\u5957\u6570\u5b57\u5316\u501f\u9605\u7ba1\u7406\u7cfb\u7edf\uff0c\u4e3b\u8981\u4e1a\u52a1\u9700\u6c42\u5982\u4e0b\uff1a \u56fe\u4e66\u4fe1\u606f\uff1a\u8bb0\u5f55\u56fe […]<\/p>\n","protected":false},"author":1,"featured_media":448,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[9],"tags":[],"class_list":["post-446","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-wenzhang"],"_links":{"self":[{"href":"https:\/\/fg2025.cn\/index.php\/wp-json\/wp\/v2\/posts\/446","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/fg2025.cn\/index.php\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/fg2025.cn\/index.php\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/fg2025.cn\/index.php\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/fg2025.cn\/index.php\/wp-json\/wp\/v2\/comments?post=446"}],"version-history":[{"count":0,"href":"https:\/\/fg2025.cn\/index.php\/wp-json\/wp\/v2\/posts\/446\/revisions"}],"wp:attachment":[{"href":"https:\/\/fg2025.cn\/index.php\/wp-json\/wp\/v2\/media?parent=446"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/fg2025.cn\/index.php\/wp-json\/wp\/v2\/categories?post=446"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/fg2025.cn\/index.php\/wp-json\/wp\/v2\/tags?post=446"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}