Re: Is it possible to stop sessions killing eachother when they all authorize as the same role?

Le mer. 14 sept. 2022 à 00:35, Bryn Llewellyn <bryn(at)yugabyte(dot)com> a écrit :

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> *guillaume(at)lelarge(dot)info <guillaume(at)lelarge(dot)info> wrote:*
> This won't answer your question
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> It has been answered now. See my "case closed" email here:
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> www.postgresql.org/message-id/B33C40D9-2B79-44C7-B527-86E672BEA71A%40yugabyte.com
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> …but still… I usually really like your scripts, it's nicely written, but
> this part seems really weird to me:
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> *bryn(at)yugabyte(dot)com <bryn(at)yugabyte(dot)com> wrote:*
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> *-- No errordo $body$declare p int not null := 0;begin for p in (
> select pid from pg_stat_activity where backend_type = 'client
> backend' and pid <> pg_backend_pid()) loop perform
> pg_terminate_backend(p); end loop;end;$body$;*
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> While your script works great, I'm wondering why you don't write it this
> way:
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> SELECT pg_terminate_backend(pid) FROM pg_stat_activity
> WHERE backend_type = 'client backend' AND pid <> pg_backend_pid();
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> As it is less code, it's quicker to understand what it does.
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> Well, yes… I have often been accused of being anally fixated on
> details—and of verbosity. This is just the old chestnut that a "select"
> statement shouldn't have side effects.
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Oh, OK, looks like a good reason to me. I will probably still do the quick
SELECT, but I understand your view on it.

> "pg_terminate_backend(p)" ought, by the book, to be a procedure. But I
> suppose that it dates from the time when PG had only user-defined functions
> (and no shipped procedures). And "perform" makes a function feel to me to
> be a bit more like a procedure than just selecting it feels. Others might
> well disagree…
>

--
Guillaume.