getData method
Implementation
Map<String, dynamic>? getData() {
String collId = _collRef.id;
if (_memoryDb[collId] == null) return null;
Map<String, dynamic>? doc = _memoryDb[collId]!.cast().firstWhere(
(doc) => doc[DBRKeys.id] == _id,
orElse: () => null,
);
return doc;
}