* @note: this returns false for multi-source replication GTID sets
* @see https://mariadb.com/kb/en/mariadb/gtid
* @see https://dev.mysql.com/doc/refman/5.6/en/replication-gtids-concepts.html
- * @return array Map of (domain => integer position) or false
+ * @return array Map of (domain => integer position); possibly empty
*/
protected function getGtidCoordinates() {
$gtidInfos = [];