compact method

@override Future<int> compact(String table, { required Duration horizon, })

Permanently removes tombstoned records whose wall-clock time is older than horizon and returns the number of reclaimed records.

Defaults to throwing UnsupportedError. Override for engines that support in-place compaction.

Implementation

@override
Future<int> compact(String table, {required Duration horizon}) async {
  final cutoff = Hlc(DateTime.now().toUtc().subtract(horizon), 0, _nodeId);
  _open.execute(
    'DELETE FROM crdt_records '
    'WHERE collection = ? AND is_deleted = 1 AND hlc_key < ?',
    [table, _hlcKey(cutoff)],
  );
  final removed = _open.updatedRows;
  if (removed > 0) _emit(table);
  return removed;
}