SELECTc.id,c.order_id,c.title,c.content,c.create_time,o.last_picFROM`orders`o,`case`cWHEREc.order_id=o.order_idORDERBYc.
SELECT c.id, c.order_id, c.title, c.content, c.create_time, o.last_pic FROM `orders` o , `case` c WHERE c.order_id = o.order_id ORDER BY c.id DESC LIMIT 15;
关于跨表提取字段的方法！
利用order_id相同字段，提取case中的id,order_id,title,content,create_time；orders表中的last_pic字段
MySql 跨表查询