Mysql 同一表中的两个不同数据

Mysql 同一表中的两个不同数据,mysql,sql,Mysql,Sql,我在MySQL中的表如下所示: 如何创建一个选择,将显示:买家的姓名,他对购买物品的评论和卖家的姓名 到目前为止,我只掌握了一半: SELECT User.name, User.surname, Realization.comment FROM User, Realization, Auction, Offer WHERE Realization.id_vote = Auction.id_voice AND Auction.id_buyer = User.id_user AND Offer.

我在MySQL中的表如下所示:

如何创建一个选择,将显示:买家的姓名,他对购买物品的评论和卖家的姓名

到目前为止,我只掌握了一半:

SELECT User.name, User.surname, Realization.comment 
FROM User, Realization, Auction, Offer 
WHERE Realization.id_vote = Auction.id_voice AND Auction.id_buyer = User.id_user AND Offer.id_offer=Auction.id_offer;

您可以尝试使用内部联接

select a.name as buyer_name, a.surname  as buyer_surname, c.comment
    e.name as seller_name, e.surname as seller_surname  
from User as a 
Inner Join Auction as b on b.id_buyer = a.id_user
inner join Realization as c on c.id_voice = b.id_voice
inner join Offer as d on d.id_offer = b.id_offer 
inner join User as e on d.id_seller = e.id_user;

编辑你的问题并把它放在那里。顺便说一句,为了获得所需的关系,您需要特定的联接而不是自动联接。除非您的数据库一次只存储一个拍卖,否则您的拍卖表需要一个拍卖ID。除非这是报价表的目的。报价表包含所有报价,否则拍卖会显示对报价产品感兴趣的人(以及他们准备支付的价格-图中未显示)。实现仅包含卖方“选择”的命题。我知道拍卖表可能比现在更好,但我认为它是简化的ebay.com数据库。好的,但如何在买家姓和卖家名之间添加一些东西呢?在这种情况下:买方写的评论?