Horton

Re: Proposal to introduce a shuffle function to intarray extension

Martin Kalcher <martin.kalcher@aboutsource.net>

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From: Martin Kalcher <martin.kalcher@aboutsource.net>
To: Tom Lane <tgl@sss.pgh.pa.us>
Cc: Thomas Munro <thomas.munro@gmail.com>, PostgreSQL Hackers <pgsql-hackers@lists.postgresql.org>
Date: 2022-07-17T09:16:28Z
Lists: pgsql-hackers, pgsql-general 
Am 17.07.22 um 05:37 schrieb Tom Lane:
> 
> Actually ... is there a reason to bother with an intarray version
> at all, rather than going straight for an in-core anyarray function?
> It's not obvious to me that an int4-only version would have
> major performance advantages.
> 
> 			regards, tom lane

Hi Tom,

thank you for your thoughts. There are two reasons for choosing an 
int4-only version. I am not familiar with postgres development (yet) and 
i was not sure how open you are about such changes to core and if the 
proposed feature is considered valuable enough to go into core. The 
second reason was ease of implementation. The intarray extension does 
not allow any NULL elements in arrays and treats multidimensional arrays 
as though they were linear. Which makes the implementation straight 
forward, because there are fewer cases to consider.

However, i will take a look at an implementation for anyarray in core.

Martin

Commits

  1. Add array_sample() and array_shuffle() functions.

  2. Use a separate random seed for SQL random()/setseed() functions.