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 FOR
SELECT 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
as
declare @count int,@s nvarchar(1000),@i int
select 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_address
into #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=1
begin
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=@@rowcount
end

if @count>0
begin
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.id
end

create Procedure [dbo].[sp_who_lock]
as
begin
declare @spid int,@bl int,
@intTransactionCountOnEntry 	int,
@intRowcount 			int,
@intCountProperties 		int,
@intCounter 			int
set nocount on
create table #tmp_lock_who (
id int identity(1,1),
spid smallint,
bl smallint)

IF @@ERROR<>0 RETURN @@ERROR

insert 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 = 1
from #tmp_lock_who

IF @@ERROR<>0 RETURN @@ERROR

if	@intCountProperties=0
select '现在没有阻塞和死锁信息' as message

-- 循环开始
while @intCounter <= @intCountProperties
begin
-- 取第一条记录
select 	@spid = spid,@bl = bl
from #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 + 1
end

drop table #tmp_lock_who
set nocount off
return 0
end

4、 临时表

select top(100) *
into #temp_table
from WOTable  as a
where StartTime=@startdate and not exists (select ID from temp_WOCode where ID=a.ID and Status=0)
and [Status]=0 and CurrentStatus<>999

update 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 <>0
begin
print 'has data, commit tran'
commit tran
end
END TRY
BEGIN CATCH
if @@trancount <>0
begin
rollback tran
end
END 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>