I have 2 subqueries, but I'm having trouble joining columns together from the same tables. I tried:
我有两个子查询，但是我无法将来自相同表的列连接在一起。我试着:
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;
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 ??
如果我用a结束查询。用户id = b。sourceid它是可以工作的，但是我如何才能在a的另一列中加入这些表呢?listid = b.destinationid ? ?
Any help appreciated.
任何帮助表示赞赏。
2 个解决方案
#1
116
Join like this:
加入这样的:
ON a.userid = b.sourceid AND a.listid = b.destinationid;
#2
39
You want to join on condition 1 AND condition 2, so simply use the AND keyword as below
您希望在条件1和条件2上加入，因此只需如下所示使用AND关键字
ON a.userid = b.sourceid AND a.listid = b.destinationid;
#1
116
Join like this:
加入这样的:
ON a.userid = b.sourceid AND a.listid = b.destinationid;
#2
39
You want to join on condition 1 AND condition 2, so simply use the AND keyword as below
您希望在条件1和条件2上加入，因此只需如下所示使用AND关键字
ON a.userid = b.sourceid AND a.listid = b.destinationid;