รบกวนขอตัวอย่างคำสั่ง sql การลบ 2 ตารางซึ่งมีข้อมูลสัมพันธ์กัน

$datadel = mysql_query("SELECT Id FROM Table1  WHERE field = '111' ");

$del1 = mysql_query("DELETE FROM Table1 WHERE field = '111' ");

$del2 = mysql_query("DELETE FROM Table2  WHERE field = '$datadel' ");

$del1 = mysql_query("DELETE FROM data_conf  WHERE id_conf = '1' ");

$del2 = mysql_query("DELETE FROM total_conf  WHERE id_conf  = '1' ");