Re: Catalog version access

Vik Fearing <vik(at)postgresfriends(dot)org> writes:
> On 2/22/21 12:48 AM, Andres Freund wrote:
>> Seems roughly reasonable. Although I wonder if we rather should make it
>> something more generic than just catversion? E.g. a wal page magic bump
>> will also require a dump/restore or pg_upgrade, but won't be detected by
>> just doing this. So perhaps we should instead add a pg_config option
>> showing all the different versions that influence on-disk compatibility?

> Do you mean one single thing somehow lumped together, or one for each
> version number?

FWIW, I think asking pg_config about this is a guaranteed way of having
version-skew-like bugs. If we're going to bother with providing a way
to get this info, we should make it possible to ask the running server.

(That would open up some security questions: do we want to let
unprivileged users know this info? I guess if version() is not
protected then this needn't be either.)

regards, tom lane