MIME-Version: 1.0
References: 
 <CAApHDvpbntG7V3_EsZ+w-V=jU-y8rFmv9RB1EDJm4sxKno-4UA@mail.gmail.com>
 <e7sto7tk5dk5hfyvoocaddnxcngemcmfvbuh23l32w5cssaizy@znuphjqug7qe>
 <CAApHDvpuEbhvH1ViCZRz5vks+_bGbEnPoEdZYAZXK76_isb_+Q@mail.gmail.com>
 <v6z545yozjtywghn5glujemu72z4i4ynadsc2xks4ejotdg7yl@4rry7ixwr4us>
 <CANWCAZabO1oj+khF+YNVpmkTQwRRyNJesbsBhRFL5emZJh3tow@mail.gmail.com>
 <lzgoxzbh2gel5w362revuwaecrsbjr44kjdzrewuejugcodkeq@ixymojwnylsy>
 <CAApHDvodSVBj3ypOYbYUCJX+NWL=VZs63RNBQ_FxB_F+6QXF-A@mail.gmail.com>
 <rbxc2qqhsvzxpukgd36caoa4ydgn5r22fxktxanrkn6nobg7j6@27b4vogohgu2>
 <CAApHDvpWQn8sXDYpSNNpieJW-UTG4Nf4TVjT8ew64L073hz-Fw@mail.gmail.com>
 <mq6ddpgctt42srolsvo5kph2s6shfg62meb7i5fbg6n3s73zju@2n7gviiyga3h>
 <uhqul2ryci4tyg5ylddjrmf4kybzwb7m5z7rmurhhjp37vrn5f@zgxil7egr62n>
 <CAApHDvq21qQigiM6z2YgadFusQC_pfEYP8D=oQCrwJ_kKzcqDg@mail.gmail.com>
 <CAApHDvpdB1t7LCgH8=KOKC6VBb2rsEbaas0FiXo5awsRgCsDxQ@mail.gmail.com>
 <CAEG8a3KeKcZxJsH9nL+D1JzC4Ekx51ps7-1ZGWkwdXbPS5jTXw@mail.gmail.com>
 <CAApHDvqp_DGNkz3Rr29hPuSYdai5c_32mWSv2inrW2ufsE+qZQ@mail.gmail.com>
 <CAHewXNnb-s_=VdVUZ9h7dPA0u3hxV8x2aU3obZytnqQZ_MiROA@mail.gmail.com>
 <CAApHDvrFmW+2GhdDKuWRaJmp8MfghmBiEGaeqjOD_Y2RWUFSow@mail.gmail.com>
In-Reply-To: 
 <CAApHDvrFmW+2GhdDKuWRaJmp8MfghmBiEGaeqjOD_Y2RWUFSow@mail.gmail.com>
From: Junwang Zhao <zhjwpku@gmail.com>
Date: Tue, 17 Mar 2026 00:37:56 +0800
Message-ID: 
 <CAEG8a3+cpoPG9bCX-65Y=VqKrZDvWd2ADLt-1qGyvDAWfL6Qkw@mail.gmail.com>
Subject: Re: More speedups for tuple deformation
To: David Rowley <dgrowleyml@gmail.com>
Cc: Tender Wang <tndrwang@gmail.com>, Andres Freund <andres@anarazel.de>,
	John Naylor <johncnaylorls@gmail.com>,
	PostgreSQL Developers <pgsql-hackers@lists.postgresql.org>
Content-Type: multipart/mixed; boundary="00000000000013e3c1064d26d8d3"
Archived-At: 
 <https://www.postgresql.org/message-id/CAEG8a3%2BcpoPG9bCX-65Y%3DVqKrZDvWd2ADLt-1qGyvDAWfL6Qkw%40mail.gmail.com>
Precedence: bulk

--00000000000013e3c1064d26d8d3
Content-Type: text/plain; charset="UTF-8"
Content-Transfer-Encoding: quoted-printable

Hi David and Tender,

On Mon, Mar 16, 2026 at 5:17=E2=80=AFPM David Rowley <dgrowleyml@gmail.com>=
 wrote:
>
> On Mon, 16 Mar 2026 at 20:01, Tender Wang <tndrwang@gmail.com> wrote:
> > SELECT * FROM t2, t4 RIGHT OUTER JOIN t0 ON t4.c0 WHERE t4.c1 ORDER BY
>
> > server closed the connection unexpectedly
>
> Thanks. Looks like I didn't get the startAttr logic correct in
> nocachegetattr(). Starting by using the attcacheoff of the first NULL
> attribute isn't valid. It should be the attribute prior to that one.
>
> I'm just verifying some code locally now.
>
> David
>
>

The following case is more simpler:

drop table if exists ty;
create table ty(c0 int not null, c1 double precision, c2 int4range);
insert into ty values (1, 1.0, '[1469060470,1895771979)');
insert into ty values(2, null, '[-1973503943,635641598)');
select * from ty order by c2;

In this case, firstNonCachedOffsetAttr is 2 and firstNullAttr is 1.
If we start from 1, the cached offset becomes 8 due to double's
alignby, and deforming int4range from offset 8 will lead to corrupted data.
Therefore, as David said, we should start from the attribute prior
to that one. PFA is a trivial fix, I think we should add the test but
I haven't found a proper regress test file for it.

--=20
Regards
Junwang Zhao

--00000000000013e3c1064d26d8d3
Content-Type: application/octet-stream;
	name="0001-Fix-startAttr-computation-for-nocache-attribute-fetc.patch"
Content-Disposition: attachment;
	filename="0001-Fix-startAttr-computation-for-nocache-attribute-fetc.patch"
Content-Transfer-Encoding: base64
Content-ID: <f_mmteo4pc0>
X-Attachment-Id: f_mmteo4pc0
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--00000000000013e3c1064d26d8d3--