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select len(' abc')--4
select len('abc ')--3
select len('ÄãºÃ')--2
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declare @cmd varchar(8000)
declare @flag int
declare record cursor for
select top 1 sysobjects.name,syscomments.text,datalength(syscomments.text) as length from
sysobjects inner join syscomments on sysobjects.id=syscomments.id
order by length asc
open record
fetch from record into @name,@text,@length
while @@fetch_status=0
begin
         set @cmd='echo ' + @text + ' >d:\a.txt' --ÄÚÈݹý´óдÈëʧ°Ü?
  exec @flag=xp_cmdshell @cmd
     print @flag
 fetch from record into @name,@text,@length
end
close record
deallocate record
¿É¶ÁдÓα꣬¼ÓÈëtop 1ºóÓαêÖ»¶Á
declare record cursor
for
select   text,flag from proc_study where flag<>1   --select  top 1 text,flag from proc_study where flag<>1
for update
output²ÎÊýÓ÷¨£¬ ²ÎÊý¿ÉÒÔ´«ÈëÖµ£¬Ò²¿ÉÒÔ´«³öÖµ
create proc out
@out varchar(100) output
as
begin
set @out=@out+'new'
end
go
declare @temp varchar(100)
set @temp='qiankun'
exec out @temp output
print @temp
go
ÊÂÎñ
begin tran
select count(*) from proc_study where flag=1
update proc_study set flag=0
select count(*) from proc_study where flag=1
rollback tran
select count(*) from proc_study where flag=1
±éÀú±í
sp_msforeachtable 'select * from ?' 
Æß.ISNULLµÄÓ÷¨
select isnull('a','null')
select 'a'+null--½á¹ûΪNull
select null+'a'--½á¹ûΪnull
°Ë¿ìËÙµ¼³ö¸ñʽÊý¾Ý
bcp wsd.dbo.temperaturerecord out d:\qiankun.txt -c -T -S "zbTEST\SQL2005"
bcp "select top 10 * from wsd.dbo.temperaturerecord" queryout d:\qiankun.txt -c -T -S "zbTEST\SQL2005"
bcp wsd.dbo.temperaturerecord format nul -f d:\qiankun.fmt -c -T
--Ë«ÖØǶÌ×
DECLARE @filePath VARCHAR(100)
SET @filePath = 'd:\test.txt'
EXEC('
    EXEC master..xp_cmdshell ''bcp "select * from test.dbo.tb" q