SQL Error: select * from (
select id,classid,titleurl,filename,title,newstime,smalltext,titlepic,onclick from ***_ecms_news where newstime union
select id,classid,titleurl,filename,title,newstime,smalltext,titlepic,onclick from ***_ecms_article where newstime union
select id,classid,titleurl,filename,title,newstime,smalltext,titlepic,onclick from ***_ecms_xianlu where newstime) a order by newstime desc limit 4
