SQL存储过程之变量使用（通过变量给SQL语句添加查询条件）
CREATE   PROCEDURE   treeforsearch   (@current   varchar(20),@name   varchar(20),@sex   varchar(20),@tel   varchar(20))   as
.....
select   id,name   from   Addresslist　where     1=1   order   by   name
//这里如何通过变量@name等的值是否是为空，来改变上面的查询条件啊？
//如：if(@name!= " ")
//{
//   select   id,name   from   Addresslist　where   1=1   and   name=@name   order   by   name     //变成这样的语句
//}
GO

------解决方案--------------------
CREATE PROCEDURE treeforsearch (@current varchar(20),@name varchar(20),@sex varchar(20),@tel varchar(20)) as

declare @sql varchar(8000)
set @sql= 'select id,name from Addresslist　where 1=1 '
if @name is not null
set @sql=@sql+ ' name= ' ' '+@name+ ' ' ' '
if @sex is not null
set @sql=@sql+ ' sex= ' ' '+@sex+ ' ' ' '
...
set @sql=@sql+ ' order by name '
exec (@sql)
go