Re: BackendKeyData is mandatory?

On 17.06.25 03:10, Tatsuo Ishii 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 think that's fine, if the server does not want to support query 
cancellation.  The current protocol description certainly does not 
support the idea that it is a hard error *not* to send BackendKeyData.

It's also worth thinking about the new protocol 3.2 longer key data.  A 
paranoid server might choose to send key data only if protocol >=3.2 is 
chosen and not if a lower, notionally less secure version is chosen.