数据库编程第四章课后作业

BEGIN ;

SET autocommit=1;
#第三题
UPDATE book SET bCount=bCount-1
	WHERE bName = "红楼梦";
UPDATE reader SET lendNum = lendNum+1
	WHERE rName = "张无忌";

COMMIT

#第四题
INSERT INTO penalty(rid,bid,pData,pType,amount)VALUES(6,1,NOW(),1,4.6);
UPDATE boorrow SET returnData=NOW()
	WHERE rid=6;
UPDATE reader SET lendNum=lendNum-1
	WHERE rName="刘冰冰";
UPDATE book SET bCount=bCount+1
	WHERE bName="西游记";
COMMIT;

ROLLBACK;
#第五题
CREATE VIEW Administrators  AS 
SELECT b.bName AS 图书名称,w.willData AS 归还日期,r.rName AS 读者姓名 FROM book b
INNER JOIN boorrow w ON w.nif = b.bid
INNER JOIN reader r ON  r.rid= w.rid

SELECT * FROM Administrators

CREATE VIEW Readers AS
SELECT b.bName AS 图书名称,b.bCount AS 馆存量,(b.bCount-(SELECT COUNT(nif) FROM boorrow)) AS 可借阅的数量 FROM book b

CREATE INDEX Title_Index 
ON book (bName)

SELECT * FROM Readers

#第六题

#备份数据
mysqldump -u root -p test > C:\backup\books.sql
enter PASSWORD:1234
#恢复数据
mysql -u root -p abc