Question

I have two tables named users and contacts. I would like to delete the records from two table at once. For that I am using the code below for now.

public function delete($userId, $contactId) {
    /* Since Values cannot be mixed (the Numbers) with control flow logic          
    (the commas) with prepared statements needs one placeholder per Value. */
    //As many question marks as array entries; the last one needs no comma
    $questionMarks = str_repeat("?,", count($userId)-1)."?";
    $sth = $this->dbh->prepare("DELETE FROM users WHERE id IN($questionMarks)");
    $sth->execute($userId);

    $questionMarks = str_repeat("?,", count($contactId)-1) . "?";
    $sth = $this->dbh->prepare("DELETE FROM contacts WHERE id IN($questionMarks)");
    $sth->execute($contactId);
}

Please note that $userId and $contactId will be an array and the count will always be equal.

How do I merge these two queries into one?

ANSWER :

The below query worked for me.

DELETE users,contacts FROM users INNER JOIN contacts WHERE users.id IN (2) AND contacts.id IN (2);

Answer 1

You need to find the way to join the tables together and use a query like

DELETE t1, t2 FROM t1 INNER JOIN t2 INNER JOIN t3
WHERE t1.id=t2.id AND t2.id=t3.id;