title: Is Postgres ON CONFLICT DO NOTHING performant on tables without auto-incrementing IDs?
body: <p>I'm aware that failed upserts will cause an increment in auto-incrementing fields, but are there any other considerations to keep in mind when using <code>ON CONFLICT DO NOTHING</code> when inserting millions of rows continuously?</p>
  <p>Will it cause any other type of bloat on the tables if they are lacking any auto-incrementing field?</p>
  <p>Is it considered a non-performant technique for large bulk upserts/inserts?</p>