internal static IQueryable <IGrouping <TKey, T> > GroupBy <T, TKey>(this IQueryable <T> queryable, Expression <Func <T, TKey> > filter)
{
if (queryable is IMongoQueryable <T> mongoQueryable)
{
return(MongoQueryable.GroupBy(mongoQueryable, filter));
}
return(Queryable.GroupBy(queryable, filter));
}