C# 根据LINQ将组拆分为实体-复合查询

假设我有这样的东西：

... //Group By A
into anotherGroupByRangeVariable
...//Group By B
           Operation =  from item in anotherGroupByRangeVariable
                        group featureTitleGroupItem by
                        someKey into operationGrouping

                        select new Operation()
                        {
                            myProperty = operationGrouping.Key,
                            ...Other Attributes
                        });

private static IQueryable<Operation> GroupByFeatureTitle(IGrouping<string, GroupByAItem> featureTitleGrouping)
        {
            return from item in anotherGroupByRangeVariable
                        group featureTitleGroupItem by
                        someKey into operationGrouping

                        select new Operation()
                        {
                            myProperty = operationGrouping.Key,
                            ...Other Attributes
                        }).AsQueryable();
        }

为什么我不能通过提取第二个

组并将其用于如下方法：

... //Group By A
into anotherGroupByRangeVariable
...//Group By B
           Operation =  from item in anotherGroupByRangeVariable
                        group featureTitleGroupItem by
                        someKey into operationGrouping

                        select new Operation()
                        {
                            myProperty = operationGrouping.Key,
                            ...Other Attributes
                        });

private static IQueryable<Operation> GroupByFeatureTitle(IGrouping<string, GroupByAItem> featureTitleGrouping)
        {
            return from item in anotherGroupByRangeVariable
                        group featureTitleGroupItem by
                        someKey into operationGrouping

                        select new Operation()
                        {
                            myProperty = operationGrouping.Key,
                            ...Other Attributes
                        }).AsQueryable();
        }

当我尝试执行它时，我得到错误：

LINQ to Entities does not recognize the method 'System.Linq.IQueryable`1[Operation] GroupByFeatureTitle(System.Linq.IGrouping`2[NotificationChannelDao+ScopeChannelType])' method, and this method cannot be translated into a store expression.

在LINQ to实体中使用多个内部group by进行组合查询以使代码更具可读性的最佳方法是什么
 是独立运行的第二个查询否，则将另一个GroupByRange变量作为参数传递给第二个查询。