Date: Thu, 15 Oct 2020 19:50:19 -0400
From: Bruce Momjian <bruce@momjian.us>
To: "Daniel Westermann (DWE)" <daniel.westermann@dbi-services.com>
Cc: Tom Lane <tgl@sss.pgh.pa.us>,
	PostgreSQL Hackers <pgsql-hackers@lists.postgresql.org>
Subject: Re: Wrong example in the bloom documentation
Message-ID: <20201015235019.GH3797@momjian.us>
References: 
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 <20201008162310.GA13054@momjian.us>
 <GVAP278MB010226D15C90933B3C2D198BD20B0@GVAP278MB0102.CHEP278.PROD.OUTLOOK.COM>
 <2622731.1602186212@sss.pgh.pa.us>
 <20201008195352.GA5062@momjian.us>
 <GVAP278MB01026C00EA4E25E35062483FD2080@GVAP278MB0102.CHEP278.PROD.OUTLOOK.COM>
 <20201009150832.GB1459@momjian.us>
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On Fri, Oct  9, 2020 at 11:08:32AM -0400, Bruce Momjian wrote:
> On Fri, Oct  9, 2020 at 05:44:57AM +0000, Daniel Westermann (DWE) wrote:
> > Hi Bruce, Tom,
> > 
> > On Thu, Oct  8, 2020 at 03:43:32PM -0400, Tom Lane wrote:
> > >> "Daniel Westermann (DWE)" <daniel.westermann@dbi-services.com> writes:
> > >> >> I was hoping someone more experienced with this would comment, but
> > >> >> seeing none, I will apply it in a day or two to all supported versions?
> > >> >> Have you tested this output back to 9.5?
> > >> 
> > >> > I hoped that as well. No, I tested down to 9.6 because the change happened in 10.
> > >> 
> > >> The patch assumes that parallel query is enabled, which is not true by
> > >> default before v10, so it should certainly not be applied before v10
> > >> (at least not without significant revisions).
> > 
> > Yes, the behavior change was in 10. Before 10 the example is fine, I would not apply that to any prior version, otherwise the whole example needs to be rewritten.
> 
> Agreed.

This is not applying to PG 12 or earlier because the patch mentions JIT,
which was only mentioned in the PG bloom docs in PG 13+.

-- 
  Bruce Momjian  <bruce@momjian.us>        https://momjian.us
  EnterpriseDB                             https://enterprisedb.com

  The usefulness of a cup is in its emptiness, Bruce Lee