pg.ddx.io  pgsql-bugs@postgresql.org mailing list archive  

help / color / mirror / Atom feed
From: Tom Lane <tgl@sss.pgh.pa.us>
To: 德哥 <digoal@126.com>
Cc: David G. Johnston <david.g.johnston@gmail.com>
Cc: pgsql-bugs@lists.postgresql.org <pgsql-bugs@lists.postgresql.org>
Subject: Re: BUG #17036: generated column cann't modifyed auto when update
Date: Thu, 27 May 2021 09:45:57 -0400
Message-ID: <1709810.1622123157@sss.pgh.pa.us> (raw)
In-Reply-To: <d89a6f8.4d3a.179ad210afa.Coremail.digoal@126.com>
References: <17036-e4d41f4221873a17@postgresql.org>
	<CAKFQuwarr8b2=2j2J4GuSV-FwqAXq38ebFR_wTUY=Lg9_YLCJg@mail.gmail.com>
	<23824c32.12e8.179ab97fa8a.Coremail.digoal@126.com>
	<CAKFQuwbkoz3zmL_bEC2ndSX5G9_3xm_+AL2fd+3OTFFH0VePow@mail.gmail.com>
	<2e46e6b5.1930.179abb8b6c0.Coremail.digoal@126.com>
	<CAKFQuwbDwpPyf=q-LPUfhiLYHhM_2X_86vXL=tQ0vESivtcN7g@mail.gmail.com>
	<d89a6f8.4d3a.179ad210afa.Coremail.digoal@126.com>

=?GBK?B?tcK45w==?= <digoal@126.com> writes:
> If the value of the immutable function changes, the immutable function should be recalculated.

You misunderstand completely.  An immutable marking on a function is a
promise from you to the system that the function's value does NOT change.
Therefore, the predicate of your statement is vacuous, and we need not
discuss whether the conclusion is interesting.  If there's some behavior
that you don't like as a consequence of your lie, then stop lying.

			regards, tom lane





view thread (15+ messages)  latest in thread

Message-ID: <1709810.1622123157@sss.pgh.pa.us>
Permalink:  ../1709810.1622123157@sss.pgh.pa.us/
Also on:    postgresql.org/message-id/1709810.1622123157@sss.pgh.pa.us

 · 

reply
Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Reply to all the recipients using the --to and --cc options:
  reply via email

  To: pgsql-bugs@postgresql.org
  Cc: tgl@sss.pgh.pa.us, digoal@126.com, david.g.johnston@gmail.com, pgsql-bugs@lists.postgresql.org
  Subject: Re: BUG #17036: generated column cann't modifyed auto when update
  In-Reply-To: <1709810.1622123157@sss.pgh.pa.us>

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

This inbox is served by DDX for PostgreSQL; see mirroring instructions
for how to clone and mirror all data and code used for this inbox