Joining two tables using the LIKE operator

Question

I'm trying to join two tables based on two values being alike. I have this so far but I'm getting a SQL error as soon as I use the %.

SELECT downloads.d_key, payer_email
FROM    paypal_log
INNER JOIN
        downloads
ON      downloads.d_key LIKE "%" + paypal_log.custom + "%"

The downloads.d_key will be within the paypal_log.custom.

I don't think `LIKE` was intended to be used in this way. It should be used in the `WHERE` clause. — Bernard, Oct 08 '12 at 16:44
This appears to have already been asked here http://stackoverflow.com/questions/1930809/mysql-join-query-using-like — James Piggot, Oct 08 '12 at 16:46
is there a way to parse the key out of `paypal_log.custom`? If d_key were 11, it could potentially find other keys of 111, 1111, etc... it's not a good way to join. — msmucker0527, Oct 08 '12 at 16:47
@JamesPiggot thanks for that link to the question it worked perfectly. Maybe posting it here again will help? Other options? — Abs, Oct 08 '12 at 16:50
Possible duplicate of [mysql join query using like?](https://stackoverflow.com/questions/1930809/mysql-join-query-using-like) — Braiam, Apr 03 '18 at 15:13

score 0 · Answer 1 · answered Oct 08 '12 at 16:46

0

Try

SELECT 'one' + 'two' FROM DUAL

and see what you get. You'll want to use

LIKE concat('%', paypal_log.custom, '%')

answered Oct 08 '12 at 16:46

dispake

score 0 · Answer 2 · answered Oct 08 '12 at 16:46

0

MySQL concatenation operator is ||. You can also use the CONCAT() function:

SELECT downloads.d_key, payer_email
FROM    paypal_log
INNER JOIN
        downloads
ON      downloads.d_key LIKE '%' || paypal_log.custom || '%' ;

As others pointed, you are probably doing something very, very wrong.

answered Oct 08 '12 at 16:46

ypercubeᵀᴹ

1

Very, very, very, very wrong. But it *should* run (and run, and run, and run. . .) – Larry Lustig Oct 08 '12 at 16:49

2 Answers2