多列MySQL子查詢

Question

經過一番研究，我現在明白我無法從子查詢中返回多列。我能做些什麼呢？

SELECT * FROM `users` WHERE `id` IN (SELECT `id1`, `id2` FROM `ids` WHERE `location` = 1) 

結果是#1241 - Operand should contain 1 column(s)

Answer 1

試試這個：

Select users.* 
    from users 
    join ids 
    on users.id IN(ids.id1, ids.id2) 
    and ids.location = 1;