Is Aggregate fatally flawed because each into clause is executed separately?

Question

Is VB.NET\'s Aggregate query fatally flawed when used as the first (outer) clause of a Linq expression with multiple Into clauses because each

Answer 1

Although it doesn't use the Aggregate keyword, you can do multiple functions in a single query using the following syntax:

Dim query = From book In books _
    Group By key = book.Subject Into Group _
    Select id = key, _
        BookCount = Group.Count, _
        TotalPrice = Group.Sum(Function(_book) _book.Price), _
        LowPrice = Group.Min(Function(_book) _book.Price), _
        HighPrice = Group.Max(Function(_book) _book.Price), _
        AveragePrice = Group.Average(Function(_book) _book.Price)

There does appear to be an issue with the Aggregate clause implementation though. Consider the following query from Northwind:

Aggregate o in Orders
into Sum(o.Freight),
Average(o.Freight),
Max(o.Freight)

This issues 3 database requests. The first two perform separate aggregate clauses. The third pulls the entire table back to the client and performs the Max on the client through Linq to Objects.