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前端时间,室友拿来一道关于mysql查询的问题:
有3张表:
1,zd_product 产品表 zp_id主键(产品id) inputtime(产品发布时间)
2,zd_order订单表 zp_id外键(产品id)zo_id主键(订单id) zo_voer_time( 订单完成时间)
3,zd_ord_pro产品订单表 zo_id外键(订单id)zp_id(产品id)
问:通过这3张表查找从产品发布到“一个月内““没有”被卖出过的产品?
在这里我也不说我们是如何讨论的了,直接上思路:
1,先查找在这一月内被卖出去的产品id,查找出来的数据:data(所查表zd_order)
2,通过第一步查找出来的数据继续查询zd_order表,不过要加个not in (data)
3,通过前两步,你已经查找出来没被卖出的产品id了,接下来你想查什么就查什么。
语句:
select * from zd_product a1 left join zd_ord_pro a3 on a1.zp_id=a3.zp_id where a1.zp_id in (select zp_id from zd_order where a1.zp_id not in (select zp_id from zd_order a2 where a2.zo_voer_time>a1.inputtime and a2.zo_voer_time
该语句未验证,如有错误,请自行修改。
提示:时间相加需转换为时间戳。bitsCN.com

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