docFields method

@override Future<Map<String, Map<String, Object?>>> docFields(String table, Iterable<String> docIds)

One indexed lookup per chunk of ids (doc_id IN (...)), never a table scan.

Implementation

@override
Future<Map<String, Map<String, Object?>>> docFields(
    String table, Iterable<String> docIds) async {
  if (_db == null) return {};
  final out = <String, Map<String, Object?>>{};
  final ids = docIds.toList();
  // Stay under SQLite's bound-parameter limit.
  const chunkSize = 400;
  for (var start = 0; start < ids.length; start += chunkSize) {
    final chunk = ids.sublist(start,
        start + chunkSize > ids.length ? ids.length : start + chunkSize);
    final rows = _open.select(
      'SELECT doc_id, field_path, value FROM crdt_records '
      'WHERE collection = ? AND is_deleted = 0 AND field_path IS NOT NULL '
      'AND doc_id IN (${List.filled(chunk.length, '?').join(', ')})',
      [table, ...chunk],
    );
    for (final r in rows) {
      (out[r['doc_id'] as String] ??= {})[r['field_path'] as String] =
          jsonDecode(r['value'] as String);
    }
  }
  return out;
}