I would assume he means creating a foreign key relationship from the posts and users table. Doesn't rails or prisma have a SQL migration tool? (Upon looking it looks like it's Active Record)

So the equivalent of

`rails db:migrate` after doing what you suggested in the interview. You could write in SQL as..

``` ALTER TABLE posts ADD COLUMN user_id INT, ADD CONSTRAINT fk_user FOREIGN KEY (user_id) REFERENCES users(id); ```

I don't know if that's what he was after but that's what my mind jumped to immediately. I'd recommend learning a bit as sometimes I've found that orms can be a lot slower than writing plain SQL for some more complex data fetching.