Horton

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

Phil Florent <philflorent@hotmail.com>

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From: Phil Florent <philflorent@hotmail.com>
To: David Rowley <david.rowley@2ndquadrant.com>
Cc: Tom Lane <tgl@sss.pgh.pa.us>, Robert Haas <robertmhaas@gmail.com>, "Amit Langote" <Langote_Amit_f8@lab.ntt.co.jp>, PostgreSQL Hackers <pgsql-hackers@postgresql.org>
Date: 2018-07-16T08:03:51Z
Lists: pgsql-hackers

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Same data as JSON: GET /api/v1/messages/:b64id/commits the thread's linked commits as JSON, with link sources. API reference →

  1. Match RelOptInfos by relids not pointer equality.

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

I get it. Thank you for this precision.

Regards

Phil

________________________________
De : David Rowley <david.rowley@2ndquadrant.com>
Envoyé : lundi 16 juillet 2018 07:48
À : Phil Florent
Cc : Tom Lane; Robert Haas; Amit Langote; PostgreSQL Hackers
Objet : Re: Internal error XX000 with enable_partition_pruning=on, pg 11 beta1 on Debian

On 16 July 2018 at 16:56, Phil Florent <philflorent@hotmail.com<mailto:philflorent@hotmail.com>> wrote:

I should post that in the general section but I am confused by the sentence "A parent partition is always going to have a lower relid than its children"

It's a little confusing since RelOptInfo has a relid field and so does RangeTblEntry. They both have completely different meanings.  RelOptInfo's relid is a number starting at 1 and continues in a gapless sequence increasing by 1 with each RelOptInfo.  These relids are completely internal to the server and don't appear in the system catalog tables.  RangeTblEntry's relid is what's in pg_class.oid.

I was talking about RelOptInfo's relid.

Using relids starting at 1 is quite convenient for allowing direct array lookups in various data structures in the planner. However it's also required to uniquely identify a relation as a single table may appear many times in a query, so trying to identify them by their oid could be ambiguous.  Also, some RTEKinds don't have storage, e.g a VALUES() clause.

--
 David Rowley                   http://www.2ndQuadrant.com/
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