public function getDatabases()
    {
        $cmd = array(
            'mysql' => 'SHOW DATABASES',
            'pgsql' => 'SELECT datname FROM pg_catalog.pg_database',
            'mssql|sybase|dblib|sqlsrv|odbc' => 'EXEC SP_HELPDB',
        );
        $query = $this->findQuery($cmd);
        if (!$query) return false;
        $result = $this->db->exec($query);
        if (!is_array($result)) return false;
        foreach($result as &$db)
            if (is_array($db)) $db = array_shift($db);
        return $result;
    }