Re: [HACKERS] Runtime Partition Pruning

David Rowley wrote:

> It's not exactly wrong but:
>
> + * are turned into a set of "pruning steps", which are then executed to
> + * produce a set of RTIs of partitions whose bounds satisfy the constraints in
> + * the step. Partitions not in the set are said to have been pruned.
>
> It's only prune_append_rel_partitions which is only used for the
> planner's pruning needs that converts the partition indexes to RTIs.
> Would it be better to mention that the output is partition indexes?
> Maybe:
>
> "which are then executed to produce a set of partition indexes whose
> bounds satisfy the constraints in the step. These partition indexes
> may then be translated into RTIs", or maybe even not mention the RTIs.

Amit had it as "indexes" also in his original. I wanted to avoid using
the "indexes" word alone, whose meaning is so overloaded. How about
this?

"... which are then executed to produce a set of partitions (as indexes
of resultRelInfo->part_rels array) that satisfy the constraints in the
step".

Maybe "the boundinfo array" instead of part_rels, which as I understand
also uses the same indexing as the other array, and partprune mostly
works based on boundinfo anyway?

Not mentioning RTIs seems fine.

--
Álvaro Herrera https://www.2ndQuadrant.com/
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