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整理的一些数据库不容易想到的SQL语句实例一

2024-07-21 02:47:28
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整理的一些数据库不容易想到的SQL语句实例一

1、行转列SQL语句

SELECT  *FROM    ( SELECT    [FID] ,                    [Weeks] ,                    [Qty]          FROM      dbo.TempTable where Weeks is not null         ) p PIVOT( SUM([Qty]) FOR [Weeks] IN ([1],[2],[3],[4],[5],[6])) AS pvt

2、游标

declare P_PRoduct_Main CURSOR FAST_FORWARD FORSELECT PID FROM [表名] order by PID-- 打开游标.   OPEN P_Product_Main   --填充数据.   FETCH NEXT FROM P_Product_Main INTO @PID   --假如检索到了数据,才处理.   WHILE @@fetch_status = 0   begin      print @PID;      end   fetch next from P_Product_Main into @PID;   end   -- 关闭游标   CLOSE P_Product_Main   --释放游标.   DEALLOCATE P_Product_Main

3、查看当前进程,或死锁进程,并能自动杀掉死进程,因为是针对死的,所以如果有死锁进程,只能查看死锁进程,当然,你可以通过参数控制,不管有没有死锁,都只查看死锁进程

create proc [dbo].[sp_lock2]@kill_lock_spid bit=1,  --是否杀掉死锁的进程,1 杀掉, 0 仅显示@show_spid_if_nolock bit=1 --如果没有死锁的进程,是否显示正常进程信息,1 显示,0 不显示asdeclare @count int,@s nvarchar(1000),@i intselect id=identity(int,1,1),标志, 进程ID=spid,线程ID=kpid,块进程ID=blocked,数据库ID=dbid, 数据库名=db_name(dbid),用户ID=uid,用户名=loginame,累计CPU时间=cpu, 登陆时间=login_time,打开事务数=open_tran, 进程状态=status, 工作站名=hostname,应用程序名=program_name,工作站进程ID=hostprocess, 域名=nt_domain,网卡地址=net_addressinto #t from( select 标志='死锁的进程',  spid,kpid,a.blocked,dbid,uid,loginame,cpu,login_time,open_tran,  status,hostname,program_name,hostprocess,nt_domain,net_address,  s1=a.spid,s2=0 from master..sysprocesses a join (  select blocked from master..sysprocesses group by blocked  )b on a.spid=b.blocked where a.blocked=0 union all select '|_牺牲品_>',  spid,kpid,blocked,dbid,uid,loginame,cpu,login_time,open_tran,  status,hostname,program_name,hostprocess,nt_domain,net_address,  s1=blocked,s2=1 from master..sysprocesses a where blocked<>0)a order by s1,s2 select @count=@@rowcount,@i=1 if @count=0 and @show_spid_if_nolock=1begin insert #t select 标志='正常的进程',  spid,kpid,blocked,dbid,db_name(dbid),uid,loginame,cpu,login_time,  open_tran,status,hostname,program_name,hostprocess,nt_domain,net_address from master..sysprocesses set @count=@@rowcountend if @count>0begin create table #t1(id int identity(1,1),a nvarchar(30),b Int,EventInfo nvarchar(255)) if @kill_lock_spid=1 begin  declare @spid varchar(10),@标志 varchar(10)  while @i<=@count  begin   select @spid=进程ID,@标志=标志 from #t where id=@i   insert #t1 exec('dbcc inputbuffer('+@spid+')')   if @标志='死锁的进程' exec('kill '+@spid)   set @i=@i+1  end end else  while @i<=@count  begin   select @s='dbcc inputbuffer('+cast(进程ID as varchar)+')' from #t where id=@i   insert #t1 exec(@s)   set @i=@i+1  end select a.*,进程的SQL语句=b.EventInfo from #t a join #t1 b on a.id=b.idend
create Procedure [dbo].[sp_who_lock]asbegindeclare @spid int,@bl int,@intTransactionCountOnEntry int,        @intRowcount int,        @intCountProperties int,        @intCounter intset nocount oncreate table #tmp_lock_who (id int identity(1,1),spid smallint,bl smallint)IF @@ERROR<>0 RETURN @@ERRORinsert into #tmp_lock_who(spid,bl) select  0 ,blocked  from (select * from master.dbo.sysprocesses where  blocked>0 ) a   where not exists(select * from (select * from master.dbo.sysprocesses where  blocked>0 ) b   where a.blocked=spid)  union select spid,blocked from master.dbo.sysprocesses where  blocked>0 IF @@ERROR<>0 RETURN @@ERROR -- 找到临时表的记录数select @intCountProperties = Count(*),@intCounter = 1from #tmp_lock_whoIF @@ERROR<>0 RETURN @@ERRORif@intCountProperties=0select '现在没有阻塞和死锁信息' as message -- 循环开始while @intCounter <= @intCountPropertiesbegin-- 取第一条记录select @spid = spid,@bl = blfrom #tmp_lock_who where Id = @intCounter begin if @spid =0             select '引起数据库死锁的是: '+ CAST(@bl AS VARCHAR(10)) + '进程号,其执行的SQL语法如下' else            select '进程号SPID:'+ CAST(@spid AS VARCHAR(10))+ '被' + '进程号SPID:'+ CAST(@bl AS VARCHAR(10)) +'阻塞,其当前进程执行的SQL语法如下' DBCC INPUTBUFFER (@bl )end -- 循环指针下移set @intCounter = @intCounter + 1end  drop table #tmp_lock_whoset nocount offreturn 0end

4、 临时表

select top(100) *into #temp_tablefrom WOTable  as awhere StartTime=@startdate and not exists (select ID from temp_WOCode where ID=a.ID and Status=0) and [Status]=0 and CurrentStatus<>999update a set a.BurdeningStatus=20,a.BurdeningDateTime=GETDATE(),a.BurdeningPerson=@userid  from   WOTable    as a  where exists (select ID from  #temp_table where ID=a.ID and Status=0)

5、事务

begin tran  --开始事务BEGIN TRY        if @@trancount <>0beginprint 'has data, commit tran'commit tranendEND TRYBEGIN CATCHif @@trancount <>0beginrollback tranendEND CATCH

6、索引

//普通索引CREATE INDEX <索引的名字> ON tablename (列名);//唯一索引CREATE UNIQUE INDEX <索引的名字> ON tablename (列名);drop index <索引的名字>


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