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Date: Tue, 28 Oct 2025 11:49:35 +0100
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Subject: Re: SQL:2011 Application Time Update & Delete
To: Paul A Jungwirth <pj@illuminatedcomputing.com>,
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On 24.10.25 19:08, Paul A Jungwirth wrote:
> The first 3 doc patches all apply to features that we released in v18,
> so it would be nice to get those reviewed/merged soon if possible.

I have looked through the documentation patches 0001 through 0003.

I suggest making the Temporal Tables chapter a section instead.  It
doesn't feel big enough to be a top-level topic.  I think it would fit
well into the Data Definition chapter, perhaps after the "System
Columns" section (section 5.6).

And then the temporal update and delete material would go into the
Data Manipulation chapter.

The syntax examples for temporal primary keys would be better if they
used complete CREATE TABLE examples instead of ALTER TABLE on some
table that is presumed to exist.  (Or you could link to where in the
documentation the table is created.)

The PostgreSQL documentation is not really a place to describe
features that don't exist.  So while it's okay to mention system time
in the glossary because it contrasts with application time, it doesn't
seem appropriate to elaborate further on this in the main body of the
documentation, unless we actually implement it.  Similarly with
periods, we can document them when we have them, but before that it's
just a distraction.

The pictures are nice.  Again, it would be helpful if you showed the
full CREATE TABLE statement beforehand, so that it is easier to
picture when kind of table structure is being reflected.

Initially, I read $5, $8, etc. as parameter numbers, not as prices.
Perhaps possible confusion could be avoided if you notionally make the
price column of type numeric and show the prices like 5.00, 8.00, etc.

I also looked over the patch "Add UPDATE/DELETE FOR PORTION OF" a bit.
I think it has a good structure now.  I'll do a more detailed review
soon.