gistfile1.txt

/**
 * Make sure that we have no duplicate emails on user creation by updating schema for mail field in users table.
 */
function apci_user_update_6003() {
  $ret = array();
  $unique_mail = array();
  $duplicates = db_query('SELECT DISTINCT a.uid, a.mail, a.name FROM users a INNER JOIN users b ON a.mail = b.mail WHERE a.uid <> b.uid ORDER BY a.uid');
  while($duplicate = db_fetch_object($duplicates)) {
    if(array_key_exists(strtolower($duplicate->mail), $unique_mail)) {
      list($mail_1, $mail_2) = split('@', $duplicate->mail);
      $unique_mail[strtolower($duplicate->mail)]['count'] +=1;
      db_query('UPDATE users SET mail="'.$mail_1.'_'.$unique_mail[strtolower($duplicate->mail)]['count'].'_'.$mail_2.'@allplayers.net" WHERE uid="'.$duplicate->uid.'"');
      watchdog('duplicates', 'Successfully changed email of duplicated account: %dup from %oldmail to %newmail', 
          array('%dup' => $duplicate->name, '%oldmail' => $duplicate->mail, '%newmail' => $mail_1.'_'.$unique_mail[strtolower($duplicate->mail)]['count'].'_'.$mail_2.'@allplayers.net'));
    } else{
      $unique_mail[strtolower($duplicate->mail)]['count'] = 0;
      $unique_mail[strtolower($duplicate->mail)]['uid'] = $duplicate->uid;
    }
  }
  db_drop_index($ret, 'users', 'mail');
  db_add_unique_key($ret, 'users', 'mail', array('mail'));
  return $ret;
}