123/www/wwwroot/xunxuetang.cn/include/db_mysqli.class.phpSELECT userid,username,company,linkurl,thumb,catid,areaid,vip,groupid,validated,business,mode FROM xxt_company WHERE groupid>5 AND catids<>'' AND areaid=34 order by userid desc LIMIT -20,20You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near '-20,20' at line 1