conference_id links $q1 = mysql_query("SELECT year, id FROM conferences WHERE year > 0"); // add the conferences_id field to each table while($r = mysql_fetch_assoc($q1)){ foreach($tables as $tableName){ $query = "UPDATE `$tableName` SET `conferences_id` = {$r['id']} WHERE `year` = {$r['year']}"; mysql_query($query); echo $query . ";\n"; } } // a one-off update unique to the award_prizes table $query = "UPDATE award_prizes SET conferences_id = -1 WHERE year = -1"; mysql_query($query); echo $query . ";\n"; } ?>