NoSuchMethodError: Class 'GeneratedColumn<int>' has no instance method 'count'. about drift

[simolus3]

Most methods in the query builder are built with extensions. This is so that Expression<int> and Expression<String> can have different methods on them. Extension members are resolved statically though, and so if you cast to dynamic they won't be available.

If you want to be able to re-use some columns in different tables, the approach described in #2866 may be a useful resource. But even without special setup, you can fix your code:

  Future<int> queryCount<T extends Table, D extends DataClass>({
    required TableInfo<T, D> tableInfo,
    required Expression<bool> whereExpr,
  }) async {
    final count = ((tableInfo as dynamic).id as Expression<int>).count();

Or, without any dynamic thanks to runtime schema introspection:

  final count = (tableInfo.columnsByName['id'] as Expression<int>).count();