LINQ Include on a one-to-many with .Where() not working?

Question

I\'m trying to query Users including each user\'s Interests, but only where an Interest meets certain criteria:

  return db.Users.Include(u => u.Interest         


        

Answer 1

Try this:

return db.Users.Include("Interests").Where(u => u.Interests.Any(i => i.TenantId == tenantId));

This causes the users to be loaded, but only where the tenantId matches. The Interests related entities will be eager loaded for those users when the query executes.

Answer 2

To include only some of the interests you won't be able to use the Include method, as it doesn't support this. You'll need to manually join the Interests with the Users:

var query = from user in db.Users
    join interest in db.Interests.Where(s => s.TenantId == tenantId)
    on user.InterestId equals interest.Id //todo:  will need to be updated
    into interests;
    select new { user, interests};