public function get_names( $type, $site_id = 0 ) {
$site_id = $this->prepare_site_id( $site_id );
$cbs = array(
self::TABLES_NETWORK_CORE => 'get_core_network_tables',
self::TABLES_SITE_ALL => 'get_all_site_tables',
self::TABLES_SITE_CORE => 'get_core_site_tables',
self::TABLES_SITE_CUSTOM => 'get_custom_site_tables',
);
return in_array( $site_id, array_keys( $cbs ), TRUE )
? $this->$cbs[$site_id]
: array();
}