Updating a user role when a class (group) is flagged as finished

function mymodule_training_class_node_form_submit($form, &$form_state) {

  if ($form_state['input']['field_class_is_finished']['und'] == 1) {
    $nid = $form_state['values']['nid'];  
                
    $query = db_select('og_membership', 'ogm')
      ->condition('ogm.gid', $nid, '=')
      ->fields('ogm', array('etid'));                           
    $result = $query->execute();
                
    foreach ($result as $record) {
      $uid = $record->etid;
      _mymodule_training_class_assign_alumni_role($uid);
    }   
  }
}

function _mymodule_training_class_assign_alumni_role($uid){

  $rid = db_select("users_roles", "ur")
    ->fields("ur", array("rid"))
    ->condition('ur.uid', $uid, '=')
    ->execute()
    ->fetchField();
  
  if (empty($rid)) {  
    db_insert('users_roles')
    ->fields(array(
      'uid' => $uid,
      'rid' => ALUMNI,
    ))
    ->execute();
  }     
}

mysql> describe field_data_field_class_is_finished
    -> ;
+-------------------------------+------------------+------+-----+---------+-------+
| Field                         | Type             | Null | Key | Default | Extra |
+-------------------------------+------------------+------+-----+---------+-------+
| entity_type                   | varchar(128)     | NO   | PRI |         |       |
| bundle                        | varchar(128)     | NO   | MUL |         |       |
| deleted                       | tinyint(4)       | NO   | PRI | 0       |       |
| entity_id                     | int(10) unsigned | NO   | PRI | NULL    |       |
| revision_id                   | int(10) unsigned | YES  | MUL | NULL    |       |
| language                      | varchar(32)      | NO   | PRI |         |       |
| delta                         | int(10) unsigned | NO   | PRI | NULL    |       |
| field_class_is_finished_value | int(11)          | YES  | MUL | NULL    |       |
+-------------------------------+------------------+------+-----+---------+-------+
8 rows in set (0.00 sec)

mysql> mysql> describe og_membership;
+-------------+------------------+------+-----+---------+----------------+
| Field       | Type             | Null | Key | Default | Extra          |
+-------------+------------------+------+-----+---------+----------------+
| id          | int(10) unsigned | NO   | PRI | NULL    | auto_increment |
| type        | varchar(255)     | NO   |     |         |                |
| etid        | int(10) unsigned | NO   | MUL | 0       |                |
| entity_type | varchar(32)      | NO   |     |         |                |
| gid         | int(11)          | NO   | MUL | NULL    |                |
| group_type  | varchar(32)      | NO   | MUL |         |                |
| state       | varchar(255)     | YES  |     |         |                |
| created     | int(11)          | NO   |     | 0       |                |
| field_name  | varchar(255)     | NO   |     |         |                |
| language    | varchar(12)      | NO   |     |         |                |
+-------------+------------------+------+-----+---------+----------------+
10 rows in set (0.00 sec)


mysql> select * from og_membership where gid=1304;
+------+----------------------------+-------+-------------+------+------------+-------+------------+--------------+----------+
| id   | type                       | etid  | entity_type | gid  | group_type | state | created    | field_name   | language |
+------+----------------------------+-------+-------------+------+------------+-------+------------+--------------+----------+
| 8275 | og_membership_type_default |     1 | user        | 1304 | node       | 1     | 1402485115 | og_user_node | en       |
| 8276 | og_membership_type_default | 10106 | user        | 1304 | node       | 1     | 1402485280 | og_user_node | en       |
| 8277 | og_membership_type_default | 10113 | user        | 1304 | node       | 1     | 1402485286 | og_user_node | en       |
| 8278 | og_membership_type_default | 10114 | user        | 1304 | node       | 1     | 1402485292 | og_user_node | en       |
+------+----------------------------+-------+-------------+------+------------+-------+------------+--------------+----------+
4 rows in set (0.00 sec)

mysql> describe users;
+------------------+------------------+------+-----+---------+-------+
| Field            | Type             | Null | Key | Default | Extra |
+------------------+------------------+------+-----+---------+-------+
| uid              | int(10) unsigned | NO   | PRI | 0       |       |
| name             | varchar(60)      | NO   | UNI |         |       |
| pass             | varchar(128)     | NO   |     |         |       |
| mail             | varchar(254)     | YES  | MUL |         |       |
| theme            | varchar(255)     | NO   |     |         |       |
| signature        | varchar(255)     | NO   |     |         |       |
| signature_format | varchar(255)     | YES  |     | NULL    |       |
| created          | int(11)          | NO   | MUL | 0       |       |
| access           | int(11)          | NO   | MUL | 0       |       |
| login            | int(11)          | NO   |     | 0       |       |
| status           | tinyint(4)       | NO   |     | 0       |       |
| timezone         | varchar(32)      | YES  |     | NULL    |       |
| language         | varchar(12)      | NO   |     |         |       |
| picture          | int(11)          | NO   | MUL | 0       |       |
| init             | varchar(254)     | YES  |     |         |       |
| data             | longblob         | YES  |     | NULL    |       |
+------------------+------------------+------+-----+---------+-------+
16 rows in set (0.01 sec)

mysql> select * from users where uid=10106;
+-------+----------------------+---------------------------------------------------------+------------------------------------------------+-------+-----------+------------------+------------+------------+-------+--------+------------------+----------+---------+------------------------------------------------+------+
| uid   | name                 | pass                                                    | mail                                           | theme | signature | signature_format | created    | access     | login | status | timezone         | language | picture | init                                           | data |
+-------+----------------------+---------------------------------------------------------+------------------------------------------------+-------+-----------+------------------+------------+------------+-------+--------+------------------+----------+---------+------------------------------------------------+------+
| 10106 | user_authenticated_1 | $S$DBGDqh770IDr09aztKD8Ey8aNGxwx8iiCaYo/rGCcBpa5XzNKnDF | [email protected] |       |           | full_html        | 1401792983 | 1401794533 |     0 |      1 | America/New_York |          |       0 | [email protected] | NULL |
+-------+----------------------+---------------------------------------------------------+------------------------------------------------+-------+-----------+------------------+------------+------------+-------+--------+------------------+----------+---------+------------------------------------------------+------+
1 row in set (0.00 sec)

mysql> select * from users where uid=10113;
+-------+----------------------+---------------------------------------------------------+------------------------------------------------+-------+-----------+------------------+------------+--------+-------+--------+------------------+----------+---------+------------------------------------------------+------+
| uid   | name                 | pass                                                    | mail                                           | theme | signature | signature_format | created    | access | login | status | timezone         | language | picture | init                                           | data |
+-------+----------------------+---------------------------------------------------------+------------------------------------------------+-------+-----------+------------------+------------+--------+-------+--------+------------------+----------+---------+------------------------------------------------+------+
| 10113 | user_authenticated_2 | $S$DeG84e0QP/H2h2rGv6cw93krL3CDoQ6CZOzhiSQCZa4OpZOAeP21 | [email protected] |       |           | full_html        | 1402485227 |      0 |     0 |      1 | America/New_York |          |       0 | [email protected] | NULL |
+-------+----------------------+---------------------------------------------------------+------------------------------------------------+-------+-----------+------------------+------------+--------+-------+--------+------------------+----------+---------+------------------------------------------------+------+
1 row in set (0.00 sec)

mysql> select * from users where uid=10114;
+-------+----------------------+---------------------------------------------------------+------------------------------------------------+-------+-----------+------------------+------------+--------+-------+--------+------------------+----------+---------+------------------------------------------------+------+
| uid   | name                 | pass                                                    | mail                                           | theme | signature | signature_format | created    | access | login | status | timezone         | language | picture | init                                           | data |
+-------+----------------------+---------------------------------------------------------+------------------------------------------------+-------+-----------+------------------+------------+--------+-------+--------+------------------+----------+---------+------------------------------------------------+------+
| 10114 | user_authenticated_3 | $S$D4xWR53hWUcyoZmIuZOLv7K8oasOsPCmqWaQGT.kpMQiX9k7XpfD | [email protected] |       |           | full_html        | 1402485256 |      0 |     0 |      1 | America/New_York |          |       0 | [email protected] | NULL |
+-------+----------------------+---------------------------------------------------------+------------------------------------------------+-------+-----------+------------------+------------+--------+-------+--------+------------------+----------+---------+------------------------------------------------+------+
1 row in set (0.00 sec)



mysql> select rid from users_roles where uid=10106;
+-----+
| rid |
+-----+
|   7 |
+-----+
1 row in set (0.00 sec)