Rails association in concerns

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I am using concerns for my rails application. I've different kind of
users so I have made a "loggable.rb" concern.

In my concern I have
´´´
included do
        has_one :auth_info
    end
´´´

because every of my user that will include the concern will have an
association with auth_info table.

The problem is, what foreign keys I need to put in my auth_info table?

E.G

I've 3 kind of users:

customer
seller
visitor
If I had only customer, in my table scheme I would have put the field

"id_customer"
but in my case?

Maybe this can help you https://robots.thoughtbot.com/whats-the-deal-with-rails-polymorphic-associations

search google about polymorphic associations