I have a query below where I want to search a table to find the top row with 1 or 2 empty positions. But it never returns the correct "referral_id". If I remove the "ref_user_1" and "ref_user_2" conditions from the query, then of course it will return the correct referral id. But those conditions are important for me to have. Is having "AND" and "OR" conditions in the same query against the rules? If so what's the solution for this problem?
$find_sponsor = $db->prepare("SELECT * FROM referrals WHERE referred_by = :referred_by AND ref_user_1 = :ref_user_1 OR ref_user_2 = :ref_user_2 ORDER