SQL Server觸發器和事務用法示例

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

新增和刪除觸發器

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

更新觸發器和事務

事務主要用在數據的保護，在多表更新時，事務保存所有事務下的更新語句就不會提交，數據也就不能更新成功

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
   declare @cname varchar(100);
   select @cname = cname from inserted; --保存更新後的內容
   update t_c2 set cname = @cname where cid = (select cid from deleted); --更新
   if (@@error <> 0)
   begin
    rollback transaction triUpdate; --事務回滾
   end
   else
   begin
    commit transaction triUpdate;  --事務提交
   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 條件統計時的使用

select
sum(case when z.watchName='注冊監理工程師' 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數據庫程序設計有所幫助。