SQL Server觸發(fā)器和事務(wù)用法示例

更新時間：2016年07月25日 15:11:18 作者：ajunfly

這篇文章主要介紹了SQL Server觸發(fā)器和事務(wù)用法,結(jié)合實例形式分析了SQL Server觸發(fā)器、事務(wù)、存儲過程、游標、視圖等的相關(guān)定義與使用方法,需要的朋友可以參考下

本文實例講述了SQL Server觸發(fā)器和事務(wù)用法。分享給大家供大家參考，具體如下：

新增和刪除觸發(fā)器

alter trigger tri_TC on t_c
  for INSERT,delete
as
begin
  set XACT_ABORT ON
  declare @INSERTCOUNT int;
  declare @DELETECOUNT int;
  declare @UPDATECOUNT int;
  set @INSERTCOUNT = (select COUNT(*) from inserted);
  set @DELETECOUNT = (select COUNT(*) from deleted);
  set @UPDATECOUNT = ()
  if(@INSERTCOUNT > 0)
  begin
   insert into t_c2 select * from inserted;
  end
  else if(@DELETECOUNT > 0)
  begin
   delete t_c2 where exists(select temp.cid from deleted temp where temp.cid=t_c2.cid);
  end
end

更新觸發(fā)器和事務(wù)

事務(wù)主要用在數(shù)據(jù)的保護，在多表更新時，事務(wù)保存所有事務(wù)下的更新語句就不會提交，數(shù)據(jù)也就不能更新成功

alter trigger tri_TC_Update on t_c
  for update
as
begin
  declare @delcount int;
  set @delcount = (select count(*) from deleted);
  if(@delcount > 0)
  begin
   begin transaction triUpdate --定義事務(wù)
   declare @cname varchar(100);
   select @cname = cname from inserted; --保存更新后的內(nèi)容
   update t_c2 set cname = @cname where cid = (select cid from deleted); --更新
   if (@@error <> 0)
   begin
    rollback transaction triUpdate; --事務(wù)回滾
   end
   else
   begin
    commit transaction triUpdate;  --事務(wù)提交
   end
  end
end

存儲過程

if(exists(select name from sysobjects s where s.name='pro_fun' and s.type='p'))
  drop procedure pro_fun
go
  create procedure pro_fun
as
  select * from table
go
exec pro_fun

游標

declare @qybh varchar(10)
declare cur cursor for
  select distinct qybh from PJ_EnterpriseInput
open cur
fetch next from cur into @qybh
while @@fetch_status = 0
 begin
  print(@qybh)
  fetch next from cur into @qybh
 end
close cur
deallocate cur

視圖

alter view CreateView
as
 select qybh from CreateView
go

定義方法

alter function funName(@str1 varchar(10),@str2 varchar(10))
returns varchar(10)
as
begin
  declare @returnStr varchar(10)
  set @returnStr = 'false'
  if(@str1 > @str2)
    set @returnStr = 'true'
  return @returnStr
end
select dbo.funName(... , ...)

定義表變量

declare @qybhTable table (id varchar(32),qybh varchar(30))
insert into @qybhTable
select id,qybh from PJ_EnterpriseInput
select * from @qybhTable

case when then 條件統(tǒng)計時的使用

select
sum(case when z.watchName='注冊監(jiān)理工程師' then 1 else 0 end),
sum(case when z.watchName='xinza' then 1 else 0 end),
sum(case when z.watchName='監(jiān)理員' then 1 else 0 end)
from zu_corjl z
right join zu_corjltemp t on t.corID=z.corID

希望本文所述對大家SQL Server數(shù)據(jù)庫程序設(shè)計有所幫助。

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