sql-server触发器

触发器

1）	建立一个存储过程，当考试服务器选择相应考试科目时，查询出所有选修了该课程的学生。建立state表ExamState，显示Sid，Cid，state，score，备注。state默认为0（0表示未登录，1表示已登录，2表示正在考试，3表示交卷，4表示异常）。备注状态默认为Null。建立S-ST表（Sid，题号，答案，标准答案）。
create proc examC @cname nvarchar(20)
as
 begin
   if exists(select * from sysobjects where name='examstate' and type='U')
     drop table examstate
   create table examstate(Sid char(10),sname nvarchar(20),Cid nchar(3),state int default 0,score int default Null,beizhu nvarchar(20) default Null)
   insert into  examstate 
   select S.Sid,sname,C.Cid,0,NULL,Null from SC,C,S where SC.Cid=C.Cid and S.Sid=SC.Sid and cname=@cname
   if exists(select * from sysobjects where name='S_ST' and type='U')
     drop table S_ST
   create table S_ST(Sid nchar(10),Tid int,answer nchar(1),biaozhunanser nchar(1))
 end
 
 exec  examC '数据库原理'
 select * from examstate
 select * from S_ST
 
 


2)  建立一个存储过程，如果examstate存在该Sid，将examstate状态置为1，返回1，表示登录成功。反之返回0，表示登录失败。
create proc loginproc @sid varchar(10),@result varchar(50) output
as
begin
  if exists(select * from examstate where Sid=@sid)
    begin
       declare @zt int
       select @zt=state from examstate where Sid=@sid
       if(@zt=3)
          set @result='已经交卷，不能重复登录'
       else if(@zt=4)
          set @result='请监考老师输入二次登陆密码'
       else if(@zt=0)
          begin
            set @result='登陆成功'
            update examstate set state=1 where  Sid=@sid
          end
    end
  else
    set @result='不存在该用户'   
end


declare @res varchar(50)
exec loginproc '2017071102',@res output
print @res
select * from examstate
 
3）	建立一个触发器，当ExamState表中state从0变成1时，随机从ST表中抽取10到试题存入S—_ST表中。
create trigger ct on examstate after update 
as
begin
  declare @statestart int,@stateend int,@sid char(10)
  select @statestart=state,@sid=Sid from deleted 
  select @stateend=state from inserted
  if(@statestart=0 and @stateend=1)
   begin
      insert into S_ST (Tid,answer ,biaozhunanser,Sid)
      SELECT top 10 id,NULL,answer,@sid FROM ST ORDER BY NEWID()      
   end
end

select * from S_ST
select * from ST

delete from S_ST
update examstate set state=1 where Sid='2017071102'



create proc showexamdata @pageIndex int,@pageSize int,@sid nchar(10)
as
begin
 declare @start int,@end int
 set @start = (@pageIndex - 1) * @pageSize + 1  
 set @end = @pageIndex * @pageSize  
 select problem,optionA,optionB,optionC,optionD from ST where id in(
   select Tid from   
   (  
    select *,rank() OVER (ORDER BY Tid) AS RowNo   
    from S_ST
    where sid=@sid
    )  
   as list   
  where RowNo between @start and @end 
 )
end


exec showexamdata 2,5,'2017071102'



4）	建立一个触发器，当ExamState表中state变成3时，计算该考生的分数（满分100）写入ExamState表中。
create trigger getscore on examstate after update 
as
begin
  declare @state int,@sid char(10)
  select @state=state,@sid=Sid from inserted   
  if(@state=3)
   begin
      declare @score int
      select @score=count(*)*10 from S_ST where Sid=@sid and S_ST.biaozhunanser=answer
      update examstate set score=@score where Sid=@sid
   end
end

update examstate set state=3 where Sid='2017071102'


5）	建立一个存储过程，当服务器收分时，如果还没有交卷的考返回0,如果全部交卷返回1,并将state为0的学生在备注栏改为缺考;将state为3的备注为正常。
CREATE proc endexam @result int output
as
begin
  if exists(select * from examstate where state in(1,2,4))
     set @result=0
  else
     begin
       set @result=1
       update examstate set score=0 , beizhu='缺考' where state=0 
       update examstate set beizhu='正常' where state=3    
     end  
end

declare @res int
exec endexam @res output
print @res


select * from examstate

6)建立存储过程,将ExamState表备份至备份表ExamBackup中，如果备份成功返回1，反之返回0。
create proc backexamstate @result int output
as
begin
  select * into ExamBackup from examstate
  set @result=1
end



declare @res int
exec backexamstate  @res output
print @res

select * from exambackup


7)建立触发器，当删除examstate表时，检查系统是否存在备份表ExamBackup，如果不存在则不允许删除。

create trigger checkbf on database for drop_table 
as
begin
  if not exists(select * from sysobjects where name='ExamBackup' and type='U')
    rollback;
  if not exists(select * from sysobjects where name='ExamSTBackup' and type='U')
    select * into ExamSTBackup from S_ST;
  drop  table S_ST
end
 
drop table examstate
 

数据表
create database jxgl
go
use jxgl
go
create table T(
Tid nchar(5) primary key,
name nchar(10) not null,
sex nchar(2) default '男',
workingtime	datetime,
plandscape nchar(20),
degree nchar(10),
title nvarchar(6),
department nvarchar(20),
tel	nchar(11)
)

create table S(
Sid	nchar(10) primary key,
sname nchar(10),	
sex	nchar(2) default '男',
birthday Date,	
age	as datediff(yy,birthday,getdate()),	
entrydate date,	
plandscape nchar(10) default '团员',
nativeplace	nvarchar(20),	
class as substring(Sid,7,2)
)

create table C(
Cid	nchar(3) primary key,
cname nvarchar(20) Not null,
category nchar(4) Not null check(category in('考试','考查')) default '考试',
credit	int,
Tid	nchar(5) foreign key references T(Tid) on update cascade
)

create table SC(
Sid	nchar(10) foreign key references S(Sid) on update cascade on delete cascade,
Cid	nchar(3),
score int check(score between 0 and 100),
primary key(Sid,Cid),
foreign key(Cid) references C(Cid) on update cascade on delete cascade
)

INSERT [dbo].[T] ([Tid], [name], [sex], [workingtime], [plandscape], [degree], [title], [department], [tel]) VALUES (N'95011', N'赵西明       ', N'男 ', CAST(0x0000768300000000 AS DateTime), N'群众                  ', N'硕士        ', N'副教授', N'软件', N'13733152369')
INSERT [dbo].[T] ([Tid], [name], [sex], [workingtime], [plandscape], [degree], [title], [department], [tel]) VALUES (N'95012', N'李小平       ', N'男 ', CAST(0x0000775E00000000 AS DateTime), N'党员                  ', N'硕士        ', N'教授', N'计算机系', N'13733152370')
INSERT [dbo].[T] ([Tid], [name], [sex], [workingtime], [plandscape], [degree], [title], [department], [tel]) VALUES (N'95013', N'张爽        ', N'男 ', CAST(0x00007BC700000000 AS DateTime), N'群众                  ', N'本科        ', N'副教授', N'计算机系', N'13733152371')
INSERT [dbo].[T] ([Tid], [name], [sex], [workingtime], [plandscape], [degree], [title], [department], [tel]) VALUES (N'95014', N'李丽宁       ', N'女 ', CAST(0x00007BC700000000 AS DateTime), N'党员                  ', N'硕士        ', N'副教授', N'计算机系', N'13733152372')
INSERT [dbo].[T] ([Tid], [name], [sex], [workingtime], [plandscape], [degree], [title], [department], [tel]) VALUES (N'95015', N'张金明       ', N'男 ', CAST(0x0000812C00000000 AS DateTime), N'群众                  ', N'硕士        ', N'讲师', N'计算机系', N'13733152373')
INSERT [dbo].[T] ([Tid], [name], [sex], [workingtime], [plandscape], [degree], [title], [department], [tel]) VALUES (N'95016', N'李燕        ', N'女 ', CAST(0x000082C800000000 AS DateTime), N'党员                  ', N'硕士        ', N'讲师', N'计算机系', N'13733152374')
INSERT [dbo].[T] ([Tid], [name], [sex], [workingtime], [plandscape], [degree], [title], [department], [tel]) VALUES (N'95017', N'宛平        ', N'女 ', CAST(0x0000840B00000000 AS DateTime), N'群众                  ', N'博士        ', N'副教授', N'软件', N'13733152375')
INSERT [dbo].[T] ([Tid], [name], [sex], [workingtime], [plandscape], [degree], [title], [department], [tel]) VALUES (N'95018', N'陈江川       ', N'男 ', CAST(0x0000883900000000 AS DateTime), N'群众                  ', N'博士        ', N'讲师', N'软件', N'13733152376')
INSERT [dbo].[T] ([Tid], [name], [sex], [workingtime], [plandscape], [degree], [title], [department], [tel]) VALUES (N'95019', N'郭新        ', N'男 ', CAST(0x00008CAA00000000 AS DateTime), N'党员                  ', N'博士        ', N'讲师', N'软件', N'13733152377')
INSERT [dbo].[S] ([Sid], [sname], [sex], [birthday], [entrydate], [plandscape], [nativeplace]) VALUES (N'2017071101', N'张佳        ', N'女 ', CAST(0x3F1D0B00 AS Date), CAST(0x3C3D0B00 AS Date), N'团员        ', N'江西南昌')
INSERT [dbo].[S] ([Sid], [sname], [sex], [birthday], [entrydate], [plandscape], [nativeplace]) VALUES (N'2017071102', N'好生        ', N'男 ', CAST(0xCD1E0B00 AS Date), CAST(0x3C3D0B00 AS Date), N'团员        ', N'广州顺德')
INSERT [dbo].[S] ([Sid], [sname], [sex], [birthday], [entrydate], [plandscape], [nativeplace]) VALUES (N'2017071203', N'徐克        ', N'男 ', CAST(0xBF210B00 AS Date), CAST(0x3C3D0B00 AS Date), N'团员        ', N'江西南昌')
INSERT [dbo].[S] ([Sid], [sname], [sex], [birthday], [entrydate], [plandscape], [nativeplace]) VALUES (N'2017071204', N'叶飞        ', N'女 ', CAST(0xD1210B00 AS Date), CAST(0x3C3D0B00 AS Date), N'党员        ', N'上海')
INSERT [dbo].[S] ([Sid], [sname], [sex], [birthday], [entrydate], [plandscape], [nativeplace]) VALUES (N'2017071205', N'任伟        ', N'男 ', CAST(0x7B220B00 AS Date), CAST(0x3C3D0B00 AS Date), N'团员        ', N'北京顺义')
INSERT [dbo].[S] ([Sid], [sname], [sex], [birthday], [entrydate], [plandscape], [nativeplace]) VALUES (N'2017071206', N'江贺        ', N'男 ', CAST(0x02200B00 AS Date), CAST(0x3D3D0B00 AS Date), N'党员        ', N'福建厦门')
INSERT [dbo].[C] ([Cid], [cname], [category], [credit], [Tid]) VALUES (N'101', N'计算机基础', N'考试  ', 2, N'95011')
INSERT [dbo].[C] ([Cid], [cname], [category], [credit], [Tid]) VALUES (N'102', N'C语言', N'考试  ', 3, N'95012')
INSERT [dbo].[C] ([Cid], [cname], [category], [credit], [Tid]) VALUES (N'103', N'计算机组成原理', N'考试  ', 3, N'95012')
INSERT [dbo].[C] ([Cid], [cname], [category], [credit], [Tid]) VALUES (N'104', N'汇编语言', N'考试  ', 3, N'95014')
INSERT [dbo].[C] ([Cid], [cname], [category], [credit], [Tid]) VALUES (N'105', N'Java语言', N'考查  ', 2, N'95015')
INSERT [dbo].[C] ([Cid], [cname], [category], [credit], [Tid]) VALUES (N'106', N'操作系统', N'考试  ', 3, N'95016')
INSERT [dbo].[C] ([Cid], [cname], [category], [credit], [Tid]) VALUES (N'107', N'数据结构', N'考试  ', 3, N'95017')
INSERT [dbo].[C] ([Cid], [cname], [category], [credit], [Tid]) VALUES (N'108', N'编译原理', N'考试  ', 3, N'95017')
INSERT [dbo].[C] ([Cid], [cname], [category], [credit], [Tid]) VALUES (N'109', N'网络基础', N'考试  ', 3, N'95017')
INSERT [dbo].[C] ([Cid], [cname], [category], [credit], [Tid]) VALUES (N'110', N'数据库原理', N'考试  ', 3, N'95017')
INSERT [dbo].[C] ([Cid], [cname], [category], [credit], [Tid]) VALUES (N'120', N'SQLServer', N'考查  ', 2, N'95018')
INSERT [dbo].[SC] ([Sid], [Cid], [score]) VALUES (N'2017071101', N'101', 90)
INSERT [dbo].[SC] ([Sid], [Cid], [score]) VALUES (N'2017071101', N'102', 70)
INSERT [dbo].[SC] ([Sid], [Cid], [score]) VALUES (N'2017071101', N'103', 48)
INSERT [dbo].[SC] ([Sid], [Cid], [score]) VALUES (N'2017071101', N'105', 80)
INSERT [dbo].[SC] ([Sid], [Cid], [score]) VALUES (N'2017071102', N'102', 90)
INSERT [dbo].[SC] ([Sid], [Cid], [score]) VALUES (N'2017071102', N'104', 77)
INSERT [dbo].[SC] ([Sid], [Cid], [score]) VALUES (N'2017071102', N'106', 68)
INSERT [dbo].[SC] ([Sid], [Cid], [score]) VALUES (N'2017071102', N'107', 85)
INSERT [dbo].[SC] ([Sid], [Cid], [score]) VALUES (N'2017071102', N'109', 77)
INSERT [dbo].[SC] ([Sid], [Cid], [score]) VALUES (N'2017071102', N'110', 65)
INSERT [dbo].[SC] ([Sid], [Cid], [score]) VALUES (N'2017071102', N'120', 48)
INSERT [dbo].[SC] ([Sid], [Cid], [score]) VALUES (N'2017071203', N'102', 65)
INSERT [dbo].[SC] ([Sid], [Cid], [score]) VALUES (N'2017071203', N'104', 82)
INSERT [dbo].[SC] ([Sid], [Cid], [score]) VALUES (N'2017071203', N'105', 79)
INSERT [dbo].[SC] ([Sid], [Cid], [score]) VALUES (N'2017071203', N'107', 55)
INSERT [dbo].[SC] ([Sid], [Cid], [score]) VALUES (N'2017071203', N'110', 77)
INSERT [dbo].[SC] ([Sid], [Cid], [score]) VALUES (N'2017071203', N'120', 67)
INSERT [dbo].[SC] ([Sid], [Cid], [score]) VALUES (N'2017071204', N'101', 86)
INSERT [dbo].[SC] ([Sid], [Cid], [score]) VALUES (N'2017071204', N'102', 86)
INSERT [dbo].[SC] ([Sid], [Cid], [score]) VALUES (N'2017071204', N'104', 77)
INSERT [dbo].[SC] ([Sid], [Cid], [score]) VALUES (N'2017071204', N'105', 84)
INSERT [dbo].[SC] ([Sid], [Cid], [score]) VALUES (N'2017071204', N'106', 95)
INSERT [dbo].[SC] ([Sid], [Cid], [score]) VALUES (N'2017071204', N'108', 91)
INSERT [dbo].[SC] ([Sid], [Cid], [score]) VALUES (N'2017071204', N'110', 82)
INSERT [dbo].[SC] ([Sid], [Cid], [score]) VALUES (N'2017071205', N'101', 63)
INSERT [dbo].[SC] ([Sid], [Cid], [score]) VALUES (N'2017071205', N'102', 84)
INSERT [dbo].[SC] ([Sid], [Cid], [score]) VALUES (N'2017071205', N'103', 77)
INSERT [dbo].[SC] ([Sid], [Cid], [score]) VALUES (N'2017071206', N'107', 58)
INSERT [dbo].[SC] ([Sid], [Cid], [score]) VALUES (N'2017071206', N'108', 74)
INSERT [dbo].[SC] ([Sid], [Cid], [score]) VALUES (N'2017071206', N'109', 74)