在 ASP.NET Identity Core 中，我可以更改 UserToken 主键吗

Question

Identity generates UserToken table for me (code first). I don't like that it uses 3-part primary key and there is no specified UserTokenId column.

CREATE TABLE [UserToken] (
    [UserId] int NOT NULL,
    [LoginProvider] nvarchar(450) NOT NULL,
    [Name] nvarchar(450) NOT NULL,
    [Value] nvarchar(max),
    CONSTRAINT [PK_UserToken] PRIMARY KEY ([UserId], [LoginProvider], [Name])
);

Is it possible to change (in my C# project code) the table to use only one id column as primary key? Or is it actually even a good practice in this case?

I have read many instructions on how to change the id data type in the user table but it's a bit different case.

Answer 1

You might change the table structure manually by creating an IDENTITY column and by creating a UNIQUE index on the three columns in question...

But for what reason?

The identify framework will always look up data based on the three value tuple and not on a artificial primary key which does not reflect any real data.

An identity column might make sense in case this value is used as a reference on another table, in this case there might be a reason to have a simple foreign key instead of the three value tuple.

If you are still not convinced to leave the table as it is :-) :

If you want to customize your table/database layout that is used by ASP.NET Identity, this post might be a good starting point (Beware that this post is based on ASP.NET core identity).

Background: ASP.NET is based on a layered approach where the storage used to persist information about the ASP.NET identity information is a separate module inside the ASP.NET identity framework.

You might use this as a starting point to create your own persistence layer with your own database model.