Can we have table without primary key in entity framework?

Question

I was just practicing code first new database entity framework from msdn, I wanna know whether a table without primary key can be created in code first new database EF?

Answer 1

Sometimes adding PK is not possible because it can be read-only, super protected database of a client which you have to use. EF throws exception even on SELECT operations. When I faced that issue I was able to solve it like this (names are artificial):

[Table( "WeirdTable", Schema = "SomeSchema" )]
public class WeirdTable
{
    [Column( "ID1" )]
    public int Id1 { get; set; }

    [Column( "ID2" )]
    public int Id2 { get; set; }
}

In the code file of context:

protected override void OnModelCreating( DbModelBuilder model_builder )
{
    base.OnModelCreating( model_builder );
    model_builder.Entity().HasKey(
        t => new { t.Id1, t.Id2 }
    );
}

So basically you just need to specify which columns can be primary key.