select dp.id,dp.product_name,db.author,dcp.id,di.product_id,sum(di.product_num) from d_category_product dcp join d_product dp on (dcp.product_id=dp.id) join d_book db on (dp.id=db.id) left join d_item di on (dp.id=di.product_id) where dcp.cat_id=10 group by dp.id order by dp.id;
解决方案 »
免费领取超大流量手机卡,每月29元包185G流量+100分钟通话, 中国电信官方发货