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| 技术资料  > ASP技术 > 数据库相关 : SQL Server对select语句返回多条记录给变量赋值时的处 |  
SQL Server对select语句返回多条记录给变量赋值时的处 March 25,2004 |  
declare @user nvarchar(20) 
select @user='user1' 
use countme 
/*判断用户是否存在*/ 
declare @userweek int 
select @userweek=[week] from base where userid=@user 
select @@rowcount 
if @@rowcount=0 
return 
select @userweek 
 
最后的@userweek打印出来的结果就是记录用户名为user1的week字段的值 
 
而当我们用下面的语句选择所有记录时(没有where限制) 
declare @user nvarchar(20) 
select @user='user1' 
use countme 
/*判断用户是否存在*/ 
declare @userweek int 
select @userweek=[week] from base 
select @@rowcount 
if @@rowcount=0 
return 
select @userweek 
 
最后@userweek打印出来的值是返回的所有记录中排名最后一条记录的week字段值 
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