Re: [PATCH] Introduce array_shuffle() and array_sample()

From: Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us>
To: Martin Kalcher <martin(dot)kalcher(at)aboutsource(dot)net>
Cc: Andres Freund <andres(at)anarazel(dot)de>, Fabien COELHO <coelho(at)cri(dot)ensmp(dot)fr>, Dean Rasheed <dean(dot)a(dot)rasheed(at)gmail(dot)com>, Robert Haas <robertmhaas(at)gmail(dot)com>, Andrew Dunstan <andrew(at)dunslane(dot)net>, John Naylor <john(dot)naylor(at)enterprisedb(dot)com>, Thomas Munro <thomas(dot)munro(at)gmail(dot)com>, PostgreSQL Hackers <pgsql-hackers(at)lists(dot)postgresql(dot)org>
Subject: Re: [PATCH] Introduce array_shuffle() and array_sample()
Date: 2022-09-26 20:16:25
Message-ID: 3502301.1664223385@sss.pgh.pa.us
Views: Raw Message | Whole Thread | Download mbox | Resend email
Thread:
Lists: pgsql-general pgsql-hackers

Martin Kalcher <martin(dot)kalcher(at)aboutsource(dot)net> writes:
> [ v4-0001-Introduce-array_shuffle-and-array_sample.patch ]

I think this idea of exporting drandom()'s PRNG for all and sundry
to use is completely misguided. If we go down that path we'll
be right back in the swamp that we were in when we used random(3),
namely that (a) it's not clear what affects what, and (b) to the
extent that there are such interferences, it could be bad, maybe
even a security problem. We very intentionally decoupled drandom()
from the rest of the world at commit 6645ad6bd, and I'm not ready
to unlearn that lesson.

With our current PRNG infrastructure it doesn't cost much to have
a separate PRNG for every purpose. I don't object to having
array_shuffle() and array_sample() share one PRNG, but I don't
think it should go much further than that.

regards, tom lane

In response to

Responses

Browse pgsql-general by date

  From Date Subject
Next Message Laurenz Albe 2022-09-27 04:25:13 Re: Findout long unused tables in database
Previous Message Bryn Llewellyn 2022-09-26 18:18:34 Limiting the operations that client-side code can perform upon its database backend's artifacts

Browse pgsql-hackers by date

  From Date Subject
Next Message Robert Haas 2022-09-26 20:24:06 Re: has_privs_of_role vs. is_member_of_role, redux
Previous Message Nathan Bossart 2022-09-26 20:11:13 Re: identifying the backend that owns a temporary schema