本文介绍了在 SQL 中加入来自同一个表的两个外键的处理方法，对大家解决问题具有一定的参考价值，需要的朋友们下面随着小编来一起学习吧！
问题描述
不太清楚如何问这个问题，所以如果有人想编辑以更好地表达，请.但是我想加入一个用户表，但是该行有两个来自用户表的 FK
Not quite sure how to ask this question so if someone wants to edit to better articulate please. However I want to join on a user table however the row has two FKs from the user table
item_tbl
id | ownerId | lastModifiedById | itemName
------------------------------------------
1 | 1 | 2 | "Blog Post"
user_tbl
id | username
-------------
1 | John
2 | Sally
期望的输出(或类似的东西)
Desired output (or something like it)
Owner Username | last modified by | item
----------------------------------------------
John | Sally | "Blog Post"
目前我正在执行两个查询来获取此信息.有没有更好(阅读:更有效)的方法?
currently i'm doing two queries to get this information. Is there a better (read: more efficient) way?
推荐答案
SELECT user_tbl.username Owner, a.username Modifier, item_tbl.itemName
FROM item_tbl
JOIN user_tbl
ON item_tbl.ownerId = user_tbl.id
JOIN user_tbl a
ON item_tbl.lastModifiedById = a.id;
为那些好奇的人工作，正如 Drew 在评论中暗示的那样
worked for those curious as hinted at by Drew in comments
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