Re: Stability of queryid in minor versions

On Mon, 15 Apr 2024 at 14:09, Michael Paquier <michael@paquier.xyz> wrote:
>
> On Mon, Apr 15, 2024 at 01:31:47PM +1200, David Rowley wrote:
> > I'm unsure if "Rule of thumb" is the correct way to convey that. We
> > can't really write "We endeavour to", as who is "We".  Maybe something
> > like "Generally, it can be assumed that queryid is stable between all
> > minor versions of a major version of ..., providing that <other
> > reasons>".
>
> It sounds to me that the term "best-effort" is adapted here?  Like in
> "The compatibility of query IDs is preserved across minor versions on
> a best-effort basis.  It is possible that the post-parse-analysis tree
> changes across minor releases, impacting the value of queryid for the
> same query run across two different minor versions.".

I had another try and ended up pushing the logical / physical replica
details up to the paragraph above. It seems more relevant to mention
this in the section which details reasons why the queryid can be
unstable due to metadata variations.  I think keeping the 2nd
paragraph for reasons it's stable is a good separation of
responsibility.  I didn't include the "best-effort" word, but here's
what I did come up with.

David