Job queue as SQL table with multiple consumers (PostgreSQL)

Question

I have a typical producer-consumer problem:

Multiple producer applications write job requests to a job-table on a PostgreSQL database.

The job requests have

Answer 1

No need to do a whole table lock for this :\.

A row lock created with for update works just fine.

See https://gist.github.com/mackross/a49b72ad8d24f7cefc32 for the change I made to apinstein's answer and verified that it still works.

Final code is

update 
    tx_test_queue
set 
    status='running'
where
    job_id in (
        select
            job_id
        from
            tx_test_queue
        where
            status='queued'
        order by 
            job_id asc
        limit 1 for update
    )
returning job_id;