public virtual void TestGroupBySumMinMaxAvg()
{
var list =
db.Orders.Where(o => o.CustomerID == "ALFKI").GroupBy(o => o.CustomerID).Select(g =>
new
{
Sum = g.Sum(o => (o.CustomerID == "ALFKI" ? 1 : 1)),
Min = g.Min(o => o.OrderID),
Max = g.Max(o => o.OrderID),
Avg = g.Average(o => o.OrderID)
}).ToList();
AssertValue(1, list.Count);
AssertValue(6, list[0].Sum);
}