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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