第六章课后简单题

第一题：

事务的四个特性：

    原子性

    一致性

    隔离性

    持久性

第二题：

1.数据库的表就是你所创建的真实的表。

2.视图是来源于真实的表，为了不完全将表的数据展现可以创建此表的视图，视图中的数据来源与表，对视图的更改不会影响原表的数据。

第三题：

/*
*事务操作借书
*/
BEGIN TRANSACTION
DECLARE @errorSum int
DECLARE @RID varchar(50)
DECLARE @BID varchar(50)
SELECT @RID=RID FROM Reader WHERE RName='张无忌'
SELECT @BID=BID FROM Book WHERE BName='深入。Net平台和c#编程'
SET @errorSum=0
INSERT INTO Borrow(RID,BID)VALUES (@RID,@BID)
SET @errorSum=@errorSum+@@error
UPDATE Book SET BCount=BCount-1 WHERE BName=' 深入。Net平台和c#编程'
SET @errorSum=@errorSum+@@error
UPDATE Reader SET LendNum=LendNum+1 WHERE RName='张无忌'
SET @errorSum=@errorSum+@@error
IF @errorSum<>0
ROLLBACK TRANSACTION
ELSE
COMMIT TRANSACTION
GO

第四题;

/*
*事务操作借书
*/
BEGIN TRANSACTION

DECLARE @errorSum int
DECLARE @RID varchar(50)
DECLARE @BID varchar(50)
SELECT @RID=RID FROM Reader WHERE RName='刘冰冰'
SELECT @BID=BID FROM Book WHERE BName='西游记'
SET @errorSum=0
INSERT INTO Penalty(RID,BID,PType,Amount) VALUES(@RID,@BID,'1',5.6)
SET @errorSum=@errorSum+@@error
UPDATE Borrow SET ReturnDate=getdate() WHERE BID=@BID
SET @errorSum=@errorSum+@@error
UPDATE Reader SET LendNum=LendNum-1 WHERE RName='刘冰冰'
SET @errorSum=@errorSum+@@error
UPDATE Book SET BCount=BCount+1 WHERE BID=@BID
SET @errorSum=@errorSum+@@error
IF @errorSum<>0
ROLLBACK TRANSACTION
ELSE
COMMIT TRANSACTION
GO

第五题：USE Library
GO

--创建索引
IF EXISTS (SELECT * FROM sysindexes
WHERE name = 'IX_BOOK_BookName')
DROP INDEX Book.IX_BOOK_BookName --删除索引
/*--笔试列创建非聚集索引：填充因子为30％--*/
CREATE INDEX IX_BOOK_BookName
ON BOOK(BName)
WITH FILLFACTOR = 30
GO

--创建管理员视图
IF EXISTS (SELECT * FROM sysobjects WHERE NAME='view_borrow')
Drop VIEW view_borrow
go
CREATE VIEW view_borrow
AS
SELECT 图书名称=Book.BNAME,到期时间=Borrow.WillDate,读者姓名=Book.BNAME
from Borrow,book
with (index = IX_BOOK_BookName)
WHERE Book.BID=Borrow.BID
--order by Borrow.WillDate
GO

SELECT * FROM view_borrow

--创建读者视图
IF EXISTS(SELECT *FROM sysobjects WHERE NAME='view_book')
DROP VIEW view_book
go
CREATE VIEW view_book
As
SELECT 图书名称=BNAME,图书总量=BCount,可借阅量=BCount-(
SELECT COUNT(*) FROM Borrow WHERE returnDate is null AND Borrow.bid = Book.bid
) FROM Book
with (index = IX_BOOK_BookName)
GO

SELECT * FROM view_book