Re: Should we warn against using too many partitions?

part_doc_pg10_v5.patch :
+ query planning and execution. The query planner is generally able to
+ handle partition hierarchies up a few hundred partition. Planning times

"up TO a few hundred partition*S*" ?

part_doc_master_v5.patch:
+ Choosing the target number of partitions into which the table should be
+ divided by is also a critical decision to make.

"into which ... should be divided by" seems like a copy-editing
mistake. Did you mean to remove either the "into which" or the "by"?
I think "the target number of partitions THAT the table should be
divided into" is simple and sensible; I'm not sure I trust the version
with "into which" instead of "that", and the role of "by" is not clear
to me ("divide by" implies a divisor, but here we're talking about the
resulting chunks and not the divisor).

In this phrase (all versions):
+ That's because each partition requires its own metadata that must be
+ loaded into the local memory of each session that touches it.

I would replace "requires its own metadata that must be loaded" with
"requires its metadata to be loaded".

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