select count(*) as topiccount, first(userid) from topictable where date between 2012-03-01 and 2012-03-31 group by userid order by topiccount

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 select top 10 userid from table where timecreate between time1 and time2 group by id  order by  COUNT(0)desc

------解决方案--------------------
group by userid

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select top 10 from table where datediff(week,endtime,getdate())=0

查询一周内的数据，可以动态给值