MySQL Query Error select id,title,subtitle,class from dx_kskm_news where class='参考书' and ejxk_id in ('081200','081202','081203','081258','081276','081254','081253','081201','081271','081278','081280','081281','081265','081283','081284','081268','081259','081256','081255','081282','081251','081266','081270','081277','081261','081275','081279','081252','081257','081285','081264','081286','081288','081295','081294','081289','081290','081287','081291','081292','081296','081293','0812J1','081249','081248','0812J3','0812J6','81200','0812J2','81203','81202','81201','081297','0812Z1') order by kskm desc limit -2400,50 Warning: mysql_num_rows() expects parameter 1 to be resource, boolean given in D:\wwwroot\dddjyky\wwwroot\lanmu2.php on line 330