Question

向变量赋值的“SELECT”语句能不能与数据检索操作结合使用？

Answer 1

错误是因为检索的数据列没有全部赋值给变量

1、可以去掉count(RtID)来解决
select top 1 @RtID = RtID from bbsReply

2、可以多加一个变量保存count(RtID)
declare @RtID int, @cRtID int
select top 1 @RtID = RtID , @cRtID = count(RtID) from bbsReply group by RtID

3、如果你想保存RtID并检索数据，就只能分两步走了
select top 1 @RtID = RtID from bbsReply
select top 1 RtID , count(RtID) from bbsReply group by RtID