同一表中多列的 SQL 连接 [英] SQL join on multiple columns in same tables

问题描述

我有 2 个子查询，但是我无法将同一个表中的列连接在一起.我试过了:

I have 2 subqueries, but I'm having trouble joining columns together from the same tables. I tried:

SELECT * FROM

(SELECT userid, listid 
FROM user_views_table
WHERE date='2013-05-15' AND view_type='lists') a

JOIN

(SELECT sourceid, destinationid
FROM actions_table
WHERE date='2013-05-15' AND payloadtype='lists_user' AND actiontype='delete') b

ON a.userid = b.sourceid
ON a.listid = b.destinationid;

如果我只是用 ON a.userid = b.sourceid 结束查询，它可以工作，但是我如何也将这些表加入另一列 ON a.listid = b.目的地id ??

If I simply end the query with ON a.userid = b.sourceid it works, but how can I also join these tables on another column also ON a.listid = b.destinationid ??

感谢任何帮助.

推荐答案

你需要用AND替换第二个ON，像这样:

You need to replace the second ON with AND, like this:

ON a.userid = b.sourceid AND a.listid = b.destinationid;

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