w23j

Fun fact: A query like this will, once in a blue moon, return more than limit (here 1) row, since the inner query is executed multiple times and returns different ids, which is surprising for a lot of people. If your code does not expect that, it may cause problems. (The article seems to, since it uses a list and iteration to handle the result.)

  delete from task
  where task_id in
  ( select task_id
    from task
    order by random() -- use tablesample for better performance
    for update
    skip locked
    limit 1
  )
  returning task_id, task_type, params::jsonb as params