Re: BackendKeyData is mandatory?

On Monday, June 16, 2025, Tatsuo Ishii <ishii(at)postgresql(dot)org> wrote:

>
> My question is, BackendKeyData is mandatory or not. Currently
> Pgpool-II raises a fatal error if BackendKeyData is not sent before
> ReadyForQuery arrives. This is because without the message, frontend
> cannot send a CancelRequest message later on, as there's no secret
> key.

I wouldn’t expect a proxy to make a judgement here; but to simply forward
what does show up and otherwise stay silent. If there is proxy layer code
needed to deal with its absence ignoring the cancel attempt with a log
warning would be sufficient. Otherwise, the user has made their choices
and this is an optional feature in practice (though resorting to
pg_cancel_query make be required for truly hung processes).

David J.