2013-11-28-sql语句

1.查询表里加一列自动编号.例如下面的rowid

2.查询A表列+B表一聚合列。例如下面的sumnum

demo:

SELECT

 ROW_NUMBER() OVER(ORDER BY u.ID DESC) AS Rowid,

u.ID,u.UserName,u.TrueName,u.JoinNum,
(SELECT COUNT(1) FROM erp_MeetingAttendance) AS sumnum 
FROM ERPUser u

3.查询SqlServer端口号

--查询端口号exec sys.sp_readerrorlog 0, 1, 'listening'

4.操作语句回滚

begin tran
delete from order_info where ordercode=''
rollback tran

这只是预删除，真正删除不需要begin tran  ...........rollback tran