Re: Sequence Access Methods, round two

On Thu, 18 Jan 2024, 16:06 Peter Eisentraut, <peter@eisentraut.org> wrote:
>
> On 01.12.23 06:00, Michael Paquier wrote:
> > Please find attached a patch set that aims at implementing sequence
> > access methods, with callbacks following a model close to table and
> > index AMs, with a few cases in mind:
> > - Global sequences (including range-allocation, local caching).
> > - Local custom computations (a-la-snowflake).
>
> That's a lot of code, but the use cases are summarized in two lines?!?
>
> I would like to see a lot more elaboration what these uses cases are (I
> recognize the words, but do we have the same interpretation of them?)
> and how they would be addressed by what you are proposing, and better
> yet an actual implementation of something useful, rather than just a
> dummy test module.

At $prevjob we had a use case for PRNG to generate small,
non-sequential "random" numbers without the birthday problem occurring
in sqrt(option space) because that'd increase the printed length of
the numbers beyond a set limit. The sequence API proposed here
would've been a great alternative to the solution we found, as it
would allow a sequence to be backed by an Linear Congruential
Generator directly, rather than the implementation of our own
transactional random_sequence table.

Kind regards,

Matthias van de Meent
Neon (https://neon.tech)