MySQL Query Error select id,title,subtitle,class from dx_kskm_news where class='参考书' and ejxk_id in ('050102','050105','050106','050101','050103','050104','050107','050108','050138','050154','050158','050180','050100','050139','050168','050194','050171','050134','050177','050147','050183','050130','050181','050188','050189','050176','050191','050169','050178','050187','050144','050162','050152','050145','050179','050142','050192','050161','050193','050146','050166','050159','050148','050157','050165','050143','050186','050131','050155','050170','050132','050141','050156','050149','050136','050175','050197','050196','050195','050174','050163','050198','050199','050120','050121','050140','050150','050135','050153','050172','050126','050127','050190','050125','050123','050124','050128','0501J2','0501J3','050151','0501J9','050119','0501J1','050129','0501J4','050117','050118','50145','50106','50101','50103','50104','50105','50168','50102','50108','050300','50100','50134','050116','50107','0501J5') order by kskm desc limit -1250,50 Warning: mysql_num_rows() expects parameter 1 to be resource, boolean given in D:\wwwroot\dddjyky\wwwroot\lanmu2.php on line 330