Unable to create a constant value - only primitive types

Question

Two simple queries - the exception occurs in :

matchings.Any(u => product.ProductId == u.ProductId)

What is wrong? If I write true

Answer 1

You can try the following. It has worked for me as my ProductId os of type nullable.

IQueryable data = db.matchings.Any(u => product.ProductId.Value == u.ProductId);

or this

IQueryable data = db.matchings.Any(u => product.ProductId.Value.Equals(u.ProductId));

This worked in my case as the target id is a nullable type as it points to a 1:0 -> * relationship.