query with where crashes on sum, where removed and everything is happy

O hello!

Linq that borks:

            var wtf = (from h in Repository.FindAll<Domain.InventoryBatchHistory>() where h.NewQuantity > h.OldQuantity select h).Sum(h => h.NewQuantity);

Linq that does not bork:

            var wtf = (from h in Repository.FindAll<Domain.InventoryBatchHistory>() select h).Sum(h => h.NewQuantity);

SQL generated from borked linq:

SELECT
  SUM(NewQuantity)
FROM
  [InventoryBatchHistory]
WHERE
  ((([InventoryBatchHistory].[ArticleId] = 19 AND [InventoryBatchHistory].[MutationDate] >= '10-9-2012 0:00:00') AND [InventoryBatchHistory].[MutationDate] < '11-9-2012 0:00:00') AND [InventoryBatchHistory].[NewQuantity] > [InventoryBatchHistory].[OldQuantity])

Exception:

Operation is not valid due to the current state of the object.

   at Mindscape.LightSpeed.Linq.Plan.LinqQueryPlanExpression.ConvertType(Object obj, Type resultType)
   at Mindscape.LightSpeed.Linq.Plan.SingleQueryPlan.ExecuteImmediate(IUnitOfWork unitOfWork, Type returnType)
   at Mindscape.LightSpeed.Linq.LinqQueryProvider.Execute(Expression expression)
   at Mindscape.LightSpeed.Linq.LinqQueryProvider.System.Linq.IQueryProvider.Execute[S](Expression expression)
   at System.Linq.Queryable.Sum[TSource](IQueryable`1 source, Expression`1 selector)

Disregard, the resulting set gave NULL on the SUM which is correct. My mistake!