Sub elements are not retrieved correctly inside a query

[mouk]

Here is a failing Test:

[Fact]
public void Sub_Elements() {
var countAfterRetrieving = _db.Orders.Where(o => o.OrderID == 10537).Single().OrderDetails.Count();
var countBeforeRetrieving = _db.Orders
.Select(o => new {o.OrderID, Count = o.OrderDetails.Count()})
.Where(o => o.OrderID == 10537)
.Single()
.Count;

    Assert.Equal(countAfterRetrieving, countBeforRetrieving);

}

countBeforeRetrieving is usually the count of ALL OrderDetails

[mouk]

I'm not really sure where is the bug. It looks like if it jumps over the OrderDetails propety and queries the data base directly.

Looking at the generated SQL its clear. It generates:

SELECT [t0].[OrderID], [t0].[c0]
FROM (
  SELECT [t1].[OrderID], (
    SELECT COUNT(*)
    FROM [dbo].[Order Details] AS t2
    ) AS c0
  FROM [dbo].[Orders] AS t1
  ) AS t0
WHERE ([t0].[OrderID] = 10537)

Instead of:

SELECT [t0].[OrderID], [t0].[c0]
FROM (
  SELECT [t1].[OrderID], (
    SELECT COUNT(*)
    FROM [dbo].[Order Details] AS t2
    WHERE t2.OrderID = [t1].[OrderID] -- only rows belong to this order
    ) AS c0
  FROM [dbo].[Orders] AS t1
  ) AS t0
WHERE ([t0].[OrderID] = 10537)

I just don't know where to fix this :-)

[robconery]

Neither do I :)