MySQL Query Error select id,title,subtitle,class from dx_kskm_news where class='参考书' and ejxk_id in ('100700','100706','100702','100701','100703','100704','100740','100705','100723','100729','100722','100721','100724','100726','100731','100734','100732','100730','100733','100739','100738','100727','100745','100737','100736','100735','100743','100742','100720','100725','100746','100744','100728','100741','100753','100747','100748','100749','100754','100751','100752','1007J2','100755','1007J1','1007J3','1007J4') order by kskm desc limit -450,50 Warning: mysql_num_rows() expects parameter 1 to be resource, boolean given in D:\wwwroot\dddjyky\wwwroot\lanmu2.php on line 330