Re: proposal: psql: show current user in prompt

út 29. 8. 2023 v 14:11 odesílatel Jelte Fennema <postgres(at)jeltef(dot)nl> napsal:

> On Mon, 28 Aug 2023 at 15:00, Pavel Stehule <pavel(dot)stehule(at)gmail(dot)com>
> wrote:
> + minServerMajor = 1600;
> + serverMajor = PQserverVersion(pset.db) / 100;
>
> Instead of using the server version, we should instead use the
> protocol version negotiation that's provided by the
> NegotiateProtocolVersion message type. We should bump the requested
> protocol version from 3.0 to 3.1 and check that the server supports
> 3.1. Otherwise proxies or connection poolers might get this new
> message type, without knowing what to do with them.
>

I checked this part and this part of the code, and it looks like current
libpq doesn't allow optional requirements of higher protocol version number.

With the current state of NegotiateProtocolVersion handling I am not able
to connect to any older servers, because there is no fallback
implementation.

My personal feeling from this area is that the protocol design is done, but
it is not implemented on libpq level. My feelings can be wrong. The
protocol number is hardcoded in libpq, so I cannot change it from the
client side.

But maybe I don't see some possibility?

Regards

Pavel

>