presto-raptor-legacy/src/main/java/io/prestosql/plugin/raptor/legacy/RaptorConnector.java/RaptorConnector/finishDelete
class RaptorConnector:    private synchronized void finishDelete(UUID transactionId)
    {
        deletions.entries().stream()
                .filter(entry -> entry.getValue().equals(transactionId))
                .findFirst()
                .ifPresent(entry -> {
                    long tableId = entry.getKey();
                    deletions.remove(tableId, transactionId);
                    if (!deletions.containsKey(tableId)) {
                        unblockMaintenance(tableId);
                    }
                });
    }