sorting via PHP or MySQL?

(I've cross posted at the MySQL list as well) Here's an example with a simple table: describe collection; +------------------+---------------------+------+-----+---------------------+----------------+

| Field            | Type                | Null | Key | Default             | Extra          |
+------------------+---------------------+------+-----+---------------------+----------------+
| id               | bigint(20) unsigned |      | PRI | NULL                | auto_increment |
| receiver_id      | bigint(20) unsigned |      | MUL | 0                   |                |
| set_type_id      | int(2) unsigned     |      |     | 0                   |                |
| card_id          | int(3) unsigned     |      |     | 0                   |                |
| completed_set_id | bigint(20) unsigned |      |     | 0                   |                |
| created_on_gmt   | datetime            |      |     | 0000-00-00 00:00:00 |                |
+------------------+---------------------+------+-----+---------------------+----------------+

I want to end up with two PHP arrays. One for set_type_id = 22 and one for set_type_id=21. (1) one query method: SELECT * from collection WHERE set_type_id=22 OR set_type_id=21; ...do query... while( $row = $this->db->fetch_array_row() ){ if ($row['set_type_id'] == 21){ $array_a[] = $row; } else { $array_b[] = $row; } } (2) two query method: SELECT * from collection WHERE set_type_id=22; ...do query... while( $row = $this->db->fetch_array_row() ){ $array_a[] = $row; } SELECT * from collection WHERE set_type_id=21; ...do query... while( $row = $this->db->fetch_array_row() ){ $array_b[] = $row; } Which method is better? Take a hit using MySQL or take a hit using PHP? -James