ORDER BY NOT EXIST 在另一个表的两列中。 是否可以？

Question

I have a query ended with ORDER BY NOT EXISTS .
I am having an issue with NOT EXISTS to look at two columns from another table. The query works with col1 , but not with col2

FROM
    t1
    JOIN t2 ON t1.id = t2.id
    ...
ORDER BY NOT EXISTS
    (SELECT col1, col2
        FROM t1
    WHERE t1.id2 = t2.id2
        AND MONTH(t1.date) = MONTH(CURDATE())
    ) DESC

Answer 1

Ok, Just testing it and found out the solution, that if i use

WHERE t1.id = t2.id

and instead of

WHERE t1.id2 = t2.id2

it worked. I told them to look at the current table id PK column and not the another table id FK and it worked.