Question

Here’s my query

SELECT * FROM wp_postmeta WHERE meta_value LIKE '".$_POST['username']."' AND meta_value LIKE '".$_POST['password']."'

The thing is that the meta_value username and the meta_value password are in 2 different rows. I need to make a query that will look for both and tell me if the vars that I look for are in those rows. So I would like the result to return 1 with a simple

mysql_num_rows();

I know this is silly and should be on the same rows with different columns but I need to work with that stupid wordpress plugins who’s doing it like it want.

Answer 1

You can use the HAVING clause in conjunction with GROUP BY to retrieve rows satisfying ALL conditions that happen across multiple rows rather than columns:

SELECT
    *
FROM
    wp_postmeta
WHERE
    meta_value IN ('$filtered_username','$filtered_password')
GROUP BY
    meta_id
HAVING
    COUNT(*) = 2

Do not insert $_POST values into the query directly, that is an open call for SQL injection attacks. Because you are using the deprecated mysql_* functions: at the bare minimum, run your $_POST variables through mysql_real_escape_string(). But best to use PDO and its support for prepared statements.