// Just a version of the 'raw' sql (which may or may not be up
// to date with what's in the sql.js file) for manual testing etc.
WITH RECURSIVE candidate_job AS (
  SELECT (j).*, pg_try_advisory_xact_lock((j).id) AS locked
  FROM (
    SELECT j
    FROM job_snapshots AS j
    WHERE process_at <= now()
    ORDER BY process_at, id
    LIMIT 1
  ) AS t1
  UNION ALL (
    SELECT (j).*, pg_try_advisory_xact_lock((j).id) AS locked
    FROM (
      SELECT (
        SELECT j
        FROM job_snapshots AS j
        WHERE process_at <= now()
        AND (process_at, id) > (candidate_job.process_at, candidate_job.id)
        ORDER BY process_at, id
        LIMIT 1
      ) AS j
      FROM candidate_job
      WHERE NOT candidate_job.locked
      LIMIT 1
    ) AS t1
  )
)
SELECT * FROM candidate_job where locked;