use tablename -- 要操作的資料庫名
select @logicalfilename = 'tablename_log', -- 日誌檔名
@maxminutes = 10, -- limit on time allowed to wrap log.
@newsize = 1 -- 你想設定的日誌檔案的大小(m)
-- setup / initialize
declare @originalsize int
select @originalsize = size
from sysfiles
where name = @logicalfilename
select 'original size of ' + db_name() + ' log is ' +
convert(varchar(30),@originalsize) + ' 8k pages or ' +
convert(varchar(30),(@originalsize*8/1024)) + 'mb'
from sysfiles
where name = @logicalfilename
create table dummytrans
(dummycolumn char (8000) not null)
declare @counter int,
@starttime datetime,
@trunclog varchar(255)
select @starttime = getdate(),
@trunclog = 'backup log ' + db_name() + ' with truncate_only'
dbcc shrinkfile (@logicalfilename, @newsize)
exec (@trunclog)
-- wrap the log if necessary.
while @maxminutes > datediff (mi, @starttime, getdate()) -- time has not expired
and @originalsize = (select size from sysfiles where name = @logicalfilename)
and (@originalsize * 8 /1024) > @newsize
begin -- outer loop.
select @counter = 0
while ((@counter < @originalsize / 16) and (@counter < 50000))
begin -- update
insert dummytrans values ('fill log')
delete dummytrans
select @counter = @counter + 1
end
exec (@trunclog)
end
select 'final size of ' + db_name() + ' log is ' +
convert(varchar(30),size) + ' 8k pages or ' +
convert(varchar(30),(size*8/1024)) + 'mb'
from sysfiles
where name = @logicalfilename
drop table dummytrans
set nocount off
8、說明：更改某個表
exec sp_changeobjectowner 'tablename','dbo'
9、儲存更改全部表
create procedure dbo.user_changeobjectownerbatch
@oldowner as nvarchar(128),
@newowner as nvarchar(128)
asdeclare @name as nvarchar(128)
declare @owner as nvarchar(128)
declare @ownername as nvarchar(128)
declare curobject cursor for
select 'name' = name,
'owner' = user_name(uid)
from sysobjects
where user_name(uid)=@oldowner
order by name
open curobject
fetch next from curobject into @name, @owner
while(@@fetch_status=0)
begin
if @owner=@oldowner
begin
set @ownername = @oldowner + '.' + rtrim(@name)
exec sp_changeobjectowner @ownername, @newowner
end-- select @name,@newowner,@oldowner
fetch next from curobject into @name, @owner
endclose curobject
deallocate curobject
go10、sql server中直接迴圈寫入資料
declare @i int
set @i=1
while @i<30
begin
insert into test (userid) values(@i)
set @i=@i+1
end小記儲存過程中經常用到的本週，本月，本年函式
dateadd(wk,datediff(wk,0,getdate()),-1)
dateadd(wk,datediff(wk,0,getdate()),6)
dateadd(mm,datediff(mm,0,getdate()),0)
dateadd(ms,-3,dateadd(mm,datediff(m,0,getdate())+1,0))
dateadd(yy,datediff(yy,0,getdate()),0)
dateadd(ms,-3,dateadd(yy, datediff(yy,0,getdate())+1, 0))
上面的sql**只是乙個時間段
dateadd(wk,datediff(wk,0,getdate()),-1)
dateadd(wk,datediff(wk,0,getdate()),6)
就是表示本週時間段.
下面的sql的條件部分,就是查詢時間段在本週範圍內的:
where time between dateadd(wk,datediff(wk,0,getdate()),-1) and dateadd(wk,datediff(wk,0,getdate()),6)
而在儲存過程中
select @begintime = dateadd(wk,datediff(wk,0,getdate()),-1)
select @endtime = dateadd(wk,datediff(wk,0,getdate()),6)
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