实体框架TPC复制的主键

Question

I am aware that when using table per concrete type inheritance all derived classes share the same identity. What I would like to do is to have a seperate identity for Guest and AccountOwner.

After hours of googling I found two solutions. One is to use different seeds for derived classes, (I know how to implement this, but I dont like it), and the second one is to use different identity increments.

Base class:

public abstract class User
{
    [Key]
    [DatabaseGenerated(DatabaseGeneratedOption.Identity)]
    public int UserID { get; set; }
}

Derived class:

public class Guest : User
{
    //Other properties here
}

Derived class:

public class AccountOwner: User
{
    //Other properties here
}

If I were to use different identity increments, primary keys of Guest would look something like: 1, 3, 5, 6 and AccountOwner 2, 4, 6, 8.

The question now is,

How do I implement different primary keys auto increments?

Have I missed something? Do you have a better solution?

I dont want to change my db structure.

Answer 1

You can't implement different auto increments.

I have decided to go with Table per Hierarchy instead of Table per Hierarchy even tho I didn't want to change my structure.

Instead of three different tables I have now one, Accounts, and I'm using a Descriminator for the different types. Because I only have one table they all share the same auto increment.