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

I get it. Thank you for this precision.

Regards

Phil

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De : David Rowley <david(dot)rowley(at)2ndquadrant(dot)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(at)hotmail(dot)com<mailto:philflorent(at)hotmail(dot)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.

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