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sql编程的几个常识

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Jun 07, 2016 pm 05:56 PM

sql编程的几个常识

1、@@ROWCOUNT可以判断上一行查询操作得到的列数；
2、给变量赋值用SET @Pr_id = 13;
3、察看是否有符合条件的记录IF EXISTS (Select name FROM sysobjects Where name = 'reminder' AND type = 'TR');

说明特别是第一个,感觉在写Proce的时候,可以好好的运用
Create Proc Add
@n char(10)
as
Select a from Table1 where a = @n
if(@@RowCount0)
Begin
Update ....
End
Else
Begin
Insert ..........
End

Statement

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