MySQL Query Error select id,title,subtitle,class from dx_kskm_news where class='参考书' and ejxk_id in ('070901','070902','070903','070904','070920','070921','070900','070905','070927','070922','070923','070928','070929','070930','070931','070925','070926','070924','070935','070934') order by kskm desc limit -1600,50 Warning: mysql_num_rows() expects parameter 1 to be resource, boolean given in D:\wwwroot\dddjyky\wwwroot\lanmu2.php on line 330