高手求救！！！！！

[tongki]

以下代码，为何@_ywyxmdm变量取不出数？

--declare @_ywyxmdm varchar(5)
declare @_ywydm varchar(3)
declare @_mystr varchar(100)

set @_ywydm='017'


set @_mystr='declare @_ywyxmdm varchar(5) set @_ywyxmdm=(select xmdm from gl_xmzl where xmdm like '+''''+'%'+@_ywydm+''''+')'

exec (@_mystr)

print @_ywyxmdm

[tongki]

老是提示"必须声明变量 '@_ywyxmdm'。"

在线求救。。。

[愉快的登山者]

declare @_ywyxmdm varchar(5)
declare @_ywydm varchar(3)
declare @_mystr varchar(100)
set @_ywydm='017'
create table #temp(dm varchar(10))

set @_mystr='select xmdm from gl_xmzl where xmdm like '+''''+'%'+@_ywydm+''''+')'

insert into #temp exec (@_mystr)
set @_ywyxmdm = (select top 1 dm from #temp)
print @_ywyxmdm

[tongki]

虽然麻烦但能解决问题，多谢。接分。