title: Postgres: violates foreign key constraint
body: <p>I used a COPY command to load a bunch of data in the database and then created the primary keys and foreign keys afterwards.</p>
  
  <p>When I created one of the foreign keys, I got the error message: <code>violates foreign key constraint "some_fkey"</code> . Is there a way that I can raise the log level so that I can see on which row this violation happened so that I can go back and debug/check the data?</p>