Re: Internal error XX000 with enable_partition_pruning=on, pg 11 beta1 on Debian

Hi,

Consider the below case:

CREATE TABLE pt (a INT, b INT, c INT) PARTITION BY RANGE(a);
CREATE TABLE pt_p1 PARTITION OF pt FOR VALUES FROM (1) to (6) PARTITION BY
RANGE (b);
CREATE TABLE pt_p1_p1 PARTITION OF pt_p1 FOR VALUES FROM (11) to (44);
CREATE TABLE pt_p1_p2 PARTITION OF pt_p1 FOR VALUES FROM (44) to (66);
INSERT INTO pt (a,b,c) VALUES
(1,11,111),(2,22,222),(3,33,333),(4,44,444),(5,55,555);

-- rule on root partition to first level child,
CREATE RULE pt_rule_ptp1 AS ON UPDATE TO pt DO INSTEAD UPDATE pt_p1 SET a =
new.a WHERE a = old.a;

-- Below command end up with error
UPDATE pt SET a = 3 WHERE a = 2;
ERROR: child rel 1 not found in append_rel_array

Here update on the partition table fail, if it has rule which is define on
partition table - to redirect record on the child table.

While looking further, I found the test started failing with below commit:

commit 1b54e91faabf3764b6786915881e514e42dccf89
Author: Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us>
Date: Wed Aug 1 19:42:46 2018 -0400

Fix run-time partition pruning for appends with multiple source rels.

Error coming from below code, where its try to adjust the appendrel
attribute and end up with error from find_appinfos_by_relids().

/*
* The prunequal is presented to us as a qual for 'parentrel'.
* Frequently this rel is the same as targetpart, so we can skip
* an adjust_appendrel_attrs step. But it might not be, and
then
* we have to translate. We update the prunequal parameter
here,
* because in later iterations of the loop for child partitions,
* we want to translate from parent to child variables.
*/
if (parentrel != subpart)
{
int nappinfos;
AppendRelInfo **appinfos = find_appinfos_by_relids(root,

subpart->relids,

&nappinfos);

prunequal = (List *) adjust_appendrel_attrs(root, (Node *)
prunequal,
nappinfos,
appinfos);

pfree(appinfos);
}

Regards,

On Thu, Aug 2, 2018 at 8:36 PM, Alvaro Herrera <alvherre(at)2ndquadrant(dot)com>
wrote:

> On 2018-Aug-01, Tom Lane wrote:
>
> > David Rowley <david(dot)rowley(at)2ndquadrant(dot)com> writes:
> > > On 20 July 2018 at 01:03, David Rowley <david(dot)rowley(at)2ndquadrant(dot)com>
> wrote:
> > >> I've attached a patch intended for master which is just v2 based on
> > >> post 5220bb7533.
> >
> > I've pushed the v3 patch with a lot of editorial work (e.g. cleaning
> > up comments you hadn't).
>
> Thanks Tom, much appreciated.
>
> --
> Álvaro Herrera https://www.2ndQuadrant.com/
> PostgreSQL Development, 24x7 Support, Remote DBA, Training & Services
>
>

--
Rushabh Lathia
www.EnterpriseDB.com