asp.net 入门篇判断注册用户名是否存在

时间：2010-09-01 来源：蔚蓝的大海

asp教程.net 入门篇判断注册用户名是否存在
create procedure [dbo].[yk_marketclient_existsid]
@id int
as
declare @str varchar(6)
set @str=''
if exists(select * from dbo.yk_marketclient where id = @id)
set @str='存在'
else
set @str='不存在'
select @str
go
/*
在dal层读出存储过程选出的表的第一行第一列
根据表中的数据判断是否存在该id

select count(*) from tb where username=@username

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