MySQL Query Error select id,title,subtitle,class from dx_kskm_news where class='参考书' and ejxk_id in ('081902','081901','081955','081952','081900','081962','081903','081960','081958','081959','081956','081957','081950','081961','081954','081963','0819J4','0819J2','0819J3') 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