Re: Squash constant lists in query jumbling by default - Mailing list pgsql-hackers

From Dmitry Dolgov
Subject Re: Squash constant lists in query jumbling by default
Date
Msg-id CA+q6zcU+MF8veyyXeh3m1+y2Ti7ggtK8gsN_NpHzN-ctF_xXEg@mail.gmail.com
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In response to Re: Squash constant lists in query jumbling by default  (Dmitry Dolgov <9erthalion6@gmail.com>)
List pgsql-hackers
On Tue, Mar 25, 2025, 7:40 PM Dmitry Dolgov <9erthalion6@gmail.com> wrote:

On Tue, Mar 25, 2025, 6:28 PM Álvaro Herrera <alvherre@alvh.no-ip.org> wrote:
On 2025-Mar-25, Tom Lane wrote:
> If this GUC sticks around, it should be at least PGC_SUSET (on
> the analogy of compute_query_id) to make it harder to break
> pg_stat_statements that way.

I have no problem making it superuser-only, and I can see making "on" be
the default.  I am not opposed to removing it completely either, if we
really think that the current behavior is no longer useful for anybody.

I'm in favor of removing the GUC of course, but if memory serves there
were some folks in the patch discussion thread, who claimed they would
need to be able to keep non-squashed behavior. I don't recall if there were
particular arguments to support that, will try to find those messages again.

Nevermind, I've checked it out -- I think the case I had in mind [1] in fact
supports GUC removal:

> If anyone subtly changes jumbling logic when the extension is
active, the instance could get huge performance issues.

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