如何在MySQL中使用外键选择一行表? [英] How to select a row of table using foreign key in MySQL?

问题描述

我有两张表(第一个是账户，第二个是朋友)帐户在哪里

I have two tables (first is account and second is friend) where account looks like

//平板账户

id | name
1  | bob
2  | robin
3  | chan
4  | jack

//id 是主键

//桌友

id | user_id | frn_id
1  | 2       | 4
2  | 1       | 2
3  | 1       | 3

//user_id 和 frn_id 是账户主键的外键

// user_id and frn_id are foregin key from primary key of account

选择结果应该是这样的

id | user_id | frn_id
1  | robin   | jack
2  | bob     | robin
3  | bob     | chan

那么如何以这种方式从表朋友中选择，而不是显示user_id和frn_id，我想显示表帐户中的名称.

then how to select from table friend in a such a way so that instead of showing user_id and frn_id, I want to show name from table account.

推荐答案

我做了一些内连接查询，它对我有用

I have done some inner join query and it works for me

select f.id, a1.name as 'user', a2.name as 'friend'
from friend f
INNER join account a1 on a1.id = f.user_id
INNER join account a2 on a2.id = f.frn_id
ORDER BY f.id

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