From: Antonin Houska <ah@cybertec.at>
To: Aleksandr Parfenov <asp437@gmail.com>
cc: a.bykov@postgrespro.ru, pgsql-hackers@lists.postgresql.org
Subject: Re: Optimze usage of immutable functions as relation
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Comments: In-reply-to Aleksandr Parfenov <asp437@gmail.com>
   message dated "Sat, 20 Oct 2018 01:31:04 +0700."
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Date: Thu, 08 Nov 2018 15:08:03 +0100
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Aleksandr Parfenov <asp437@gmail.com> wrote:

> I fixed a typo and some comments. Please find new version attached.

I've checked this verstion too.

* is_simple_stable_function()

instead of fetching HeapTuple from the syscache manually, you might want to
consider using functions from lsyscache.c (get_func_rettype, get_func_retse=
t,
etc.), or adding a function that returns (subset of) the fields you need in=
 a
single call.

* pull_up_simple_function():

As you assume that ret->functions is a single-item list

	Assert(list_length(rte->functions) =3D=3D 1);

the following iteration is not necessary:

	foreach(lc, functions_list)

Also, there seems to be a lot of copy & paste from pull_up_simple_values(),=
 so
some refactoring would make sense.


--=20
Antonin Houska
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