Content-Type: multipart/alternative;
 boundary="------------xYES7cLx39hSKna6R1RTLLN8"
Message-ID: <c0c63979-43c2-4424-8fe8-56949934c9d8@gmail.com>
Date: Tue, 14 Apr 2026 21:00:01 +0300
MIME-Version: 1.0
User-Agent: Mozilla Thunderbird
Subject: Re: pg_plan_advice
To: Robert Haas <robertmhaas@gmail.com>,
 Melanie Plageman <melanieplageman@gmail.com>
Cc: Nathan Bossart <nathandbossart@gmail.com>, Tom Lane <tgl@sss.pgh.pa.us>,
 Lukas Fittl <lukas@fittl.com>,
 PostgreSQL Hackers <pgsql-hackers@lists.postgresql.org>,
 "heikki.linnakangas" <heikki.linnakangas@iki.fi>
References: 
 <CA+TgmoYuWmN-00Ec5pY7zAcpSFQUQLbgAdVWGR9kOR-HM-fHrA@mail.gmail.com>
 <CAP53Pkzn_wZ-R-cPdD9XSQ9+myPUUsPMMqVBPNG3XWXhgfm1-Q@mail.gmail.com>
 <CA+Tgmobxbju8PrY_NULtPr7b7UShp4+Jqibm2Bou8TVS69gObQ@mail.gmail.com>
 <3683430.1775173413@sss.pgh.pa.us>
 <CA+Tgmoad!kuOMJjvYe2h6aznHFeePprGEQ8CgUpRK=47sB6DMAg@mail.gmail.com>
 <3817825.1775240432@sss.pgh.pa.us>
 <CA+TgmoY+g1u-fN=3igXG-8u0Ho3V4u-ooWXCj-FQ9DA=uGek9g@mail.gmail.com>
 <3877210.1775272486@sss.pgh.pa.us>
 <CA+TgmobOOmmXSJz3e+cjTY-bA1+W0dqVDqzxUBEvGtW62whYGg@mail.gmail.com>
 <2672940.1775599547@sss.pgh.pa.us> <adZq3Rlxq3v916aG@nathan>
 <CAAKRu_Yaarv2+SJ8qoNfMG4FCLve6KrewX_KFe1vRzk2+4d9bg@mail.gmail.com>
 <CA+TgmoaEk5nBCHCWa8epb1Fff4BwroLkdYLfqisKk49qdHGVYw@mail.gmail.com>
Content-Language: en-US
From: Alexander Lakhin <exclusion@gmail.com>
In-Reply-To: 
 <CA+TgmoaEk5nBCHCWa8epb1Fff4BwroLkdYLfqisKk49qdHGVYw@mail.gmail.com>
Archived-At: 
 <https://www.postgresql.org/message-id/c0c63979-43c2-4424-8fe8-56949934c9d8%40gmail.com>
Precedence: bulk

This is a multi-part message in MIME format.
--------------xYES7cLx39hSKna6R1RTLLN8
Content-Type: text/plain; charset=UTF-8; format=flowed
Content-Transfer-Encoding: 8bit

13.04.2026 19:01, Robert Haas wrote:
> Sounds like we have a consensus. I have committed the three bug-fix
> patches (unrelated to the retry-loop stuff) ...

Thanks again for committing these fixes, Robert! With all the fixes in
place, I and SQLsmith have reached another error:
CREATE TABLE t1(a int);
CREATE TABLE t2(b int);

SELECT 1 FROM t1 WHERE EXISTS
   (SELECT 1 FROM
     (SELECT 1 FROM
       (SELECT 1) LEFT JOIN t2 ON true),
     t2 WHERE a = b);

ERROR:  XX000: unique semijoin found for relids (b 3 5 7) but not observed during planning
LOCATION:  pgpa_plan_walker, pgpa_walker.c:153

Could you please have a look?

Best regards,
Alexander
--------------xYES7cLx39hSKna6R1RTLLN8
Content-Type: text/html; charset=UTF-8
Content-Transfer-Encoding: 8bit

<!DOCTYPE html>
<html>
  <head>
    <meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
  </head>
  <body>
    <div class="moz-cite-prefix">13.04.2026 19:01, Robert Haas wrote:<br>
    </div>
    <blockquote type="cite"
cite="mid:CA+TgmoaEk5nBCHCWa8epb1Fff4BwroLkdYLfqisKk49qdHGVYw@mail.gmail.com">
      <pre wrap="" class="moz-quote-pre">Sounds like we have a consensus. I have committed the three bug-fix
patches (unrelated to the retry-loop stuff) ...
</pre>
    </blockquote>
    <br>
    Thanks again for committing these fixes, Robert! With all the fixes
    in<br>
    place, I and SQLsmith have reached another error:<br>
    CREATE TABLE t1(a int);<br>
    CREATE TABLE t2(b int);<br>
    <br>
    SELECT 1 FROM t1 WHERE EXISTS<br>
      (SELECT 1 FROM<br>
        (SELECT 1 FROM<br>
          (SELECT 1) LEFT JOIN t2 ON true),<br>
        t2 WHERE a = b);<br>
    <br>
    ERROR:  XX000: unique semijoin found for relids (b 3 5 7) but not
    observed during planning<br>
    LOCATION:  pgpa_plan_walker, pgpa_walker.c:153<br>
    <br>
    Could you please have a look?<br>
    <br>
    Best regards,<br>
    Alexander<br>
  </body>
</html>

--------------xYES7cLx39hSKna6R1RTLLN8--