From: Tom Lane <tgl@sss.pgh.pa.us>
To: Daniel Gustafsson <daniel@yesql.se>
cc: Maxim Yablokov <m.yablokov@postgrespro.ru>,
        pgsql-docs@lists.postgresql.org
Subject: Re: Example 43.6. A PL/pgSQL Trigger Function for Maintaining a
 Summary Table
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Comments: In-reply-to Daniel Gustafsson <daniel@yesql.se>
	message dated "Fri, 27 Oct 2023 15:15:12 +0200"
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Date: Fri, 27 Oct 2023 22:16:54 -0400
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Daniel Gustafsson <daniel@yesql.se> writes:
> Thanks, I'll await pushing and backpatching if Tom who committed it has
> insights into whether it was missed or if it indeed serves a purpose.

Hey, I just pushed that for somebody else, I don't claim authorship ;-)

It seems clear that the example intends to show a star-schema database
where the fact table refers to various dimension tables.  But it's
incomplete --- there's no foreign-key constraint on time_key, and
even less infrastructure for product_key or store_key.  I don't
have the cited book either, so I don't know how complete the original
example was.  Perhaps the bit in the trigger function about forbidding
updates to time_key has something to do with that model.

Anyway, I don't see any reason to object to this patch.  The extra
table isn't adding much.  My only thought is would it make sense to
change time_key to be a timestamp or timestamptz value?

			regards, tom lane