WP_Site_Query::parse_orderby( string $orderby )

	protected function parse_orderby( $orderby ) {
		global $wpdb;

		$parsed = false;

		switch ( $orderby ) {
			case 'site__in':
				$site__in = implode( ',', array_map( 'absint', $this->query_vars['site__in'] ) );
				$parsed = "FIELD( {$wpdb->blogs}.blog_id, $site__in )";
				break;
			case 'network__in':
				$network__in = implode( ',', array_map( 'absint', $this->query_vars['network__in'] ) );
				$parsed = "FIELD( {$wpdb->blogs}.site_id, $network__in )";
				break;
			case 'domain':
			case 'last_updated':
			case 'path':
			case 'registered':
				$parsed = $orderby;
				break;
			case 'network_id':
				$parsed = 'site_id';
				break;
			case 'domain_length':
				$parsed = 'CHAR_LENGTH(domain)';
				break;
			case 'path_length':
				$parsed = 'CHAR_LENGTH(path)';
				break;
			case 'id':
				$parsed = 'blog_id';
				break;
		}

		return $parsed;
	}