liveKeys method

@override Set<String> liveKeys(String table, String prefix)

All live (non-tombstoned) keys in table whose key starts with prefix.

Like liveFields but without values — returns only metadata so operations such as Collection.length can avoid I/O. Must be safe to call synchronously after init.

Implementation

@override
Set<String> liveKeys(String table, String prefix) {
  if (_db == null) return const {};
  final rows = prefix.isEmpty
      ? _open.select(
          'SELECT key FROM crdt_records '
          'WHERE collection = ? AND is_deleted = 0',
          [table],
        )
      : _open.select(
          'SELECT key FROM crdt_records '
          'WHERE collection = ? AND is_deleted = 0 AND substr(key, 1, ?) = ?',
          [table, prefix.length, prefix],
        );
  return {for (final r in rows) r['key'] as String};
}