SQL Error: select * from (
select id,classid,titleurl,filename,title,newstime,titlepic,schoolid from ***_ecms_tiaojian where schoolid= union
select id,classid,titleurl,filename,title,newstime,titlepic,schoolid from ***_ecms_feiyong where schoolid= union
select id,classid,titleurl,filename,title,newstime,titlepic,schoolid from ***_ecms_sinfo where schoolid= union
select id,classid,titleurl,filename,title,newstime,titlepic,schoolid from ***_ecms_zhinan where schoolid=
) a order by newstime desc limit 6