select a.news_tit,a.news_content ,b.news_class,c.city,
d.username,d.useremail
from news_info a,news_class b,city_info c,user_info d
where a.city_id=c.id and b.user_id=d.id and a.id=b.news_class_fid
你看一下这样可不可以
SELECT AA.NEWS_TIT,AA.NEWS_CONTENT,BB.NEWS_CLASS,CC.CITY,DD.USERNAME,
DD.USEREMAIL
FROM NEWS_INFO AA,NEWS_CLASS BB,CITY_INFO CC,USER_INFO DD