How to work around Entity Framework date time type bug?

Question

I want to get the all the monthly expired products, here is the query for that:

_customerProductsRepository
    .Where(
        d =>
        !d.ReleaseDate.HasValue &&
        EntityFunctions.AddMonths(d.RenewalDate ?? d.AcquireDate, 1) < now)
    .ToArray();

AcquireDate is the first purchase of the product and RenewalDate is the last renewal of the product.

For some reason it translates to this SQL:

SELECT
[Extent1].[CustomerDidId] AS [CustomerDidId],
[Extent1].[DidNumber] AS [DidNumber],
[Extent1].[CountryId] AS [CountryId],
[Extent1].[CustomerId] AS [CustomerId],
[Extent1].[AcquireDate] AS [AcquireDate],
[Extent1].[ReleaseDate] AS [ReleaseDate],
[Extent1].[RenewalDate] AS [RenewalDate],
[Extent1].[RenewalNotificationDate] AS [RenewalNotificationDate]
FROM [dbo].[CustomerDids] AS [Extent1]
WHERE ([Extent1].[ReleaseDate] IS NULL) AND ((DATEADD (month, 1, [Extent1].[Rene
walDate])) < @p__linq__0)

There should be a case statement referring to the '??' sign, instead - it completely removed AcquireDate column.

How can I walk-around it?

Answer 1

You have configured the property RenewalDate as required. Hence EF will optimize the query by evaluating the result of the "if" condition.