update wedonet_user set user_atime=GetDate() where id=0 update wedonet_user set isonline=0 where isonline=1 and datediff(n,user_atime,GetDate())>20 select count(*) from [wedonet_doc] where cid=108 and isdel=0 and ispass=1 and classid in (833) select top 20 id,classid,title from [wedonet_doc] where cid=108 and isdel=0 and ispass=1 and classid in (833) order by istop desc,cls asc,id desc select top 10 id,title from [wedonet_keyword] order by mycount desc