From: Alvaro Herrera <alvherre@2ndquadrant.com>
To: Justin Pryzby <pryzby@telsasoft.com>
Cc: Tom Lane <tgl@sss.pgh.pa.us>
Cc: Amit Langote <amitlangote09@gmail.com>
Cc: pgsql-hackers@lists.postgresql.org
Subject: Re: DETACH PARTITION and FOR EACH ROW triggers on partitioned tables
Date: Sun, 19 Apr 2020 15:13:29 -0400
Message-ID: <20200419191329.GA32288@alvherre.pgsql> (raw)
In-Reply-To: <20200419002206.GM26953@telsasoft.com>
On 2020-Apr-18, Justin Pryzby wrote:
> I haven't heard a compelling argument for or against either way.
>
> Maybe the worst behavior might be if, during ATTACH, we searched for a matching
> trigger, and "merged" it (marked it inherited) if it matched. That could be
> bad if someone *wanted* two triggers, which seems unlikely, but to each their
> own.
I think the simplicity argument trumps the other ones, so I agree to go
with your v3 patch proposed downthread.
What happens if you detach the parent? I mean, should the trigger
removal recurse to children?
> It occured to me that we don't currently distinguish between a trigger on a
> child table, and a trigger on a parent table which was recursively created on a
> child. That makes sense for indexes and constraints, since the objects persist
> if the table is detached, so it doesn't matter how it was defined.
>
> But if we remove trigger during DETACH, then it's *not* the same as a trigger
> that was defined on the child, and I suggest that in v13 we should make that
> visible.
Hmm, interesting point -- whether the trigger is partition or not is
important because it affects what happens on detach. I agree that we
should make it visible. Is the proposed single bit "PARTITION" good
enough, or should we indicate what's the ancestor table that defines the
partition?
--
Álvaro Herrera https://www.2ndQuadrant.com/
PostgreSQL Development, 24x7 Support, Remote DBA, Training & Services
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-hackers@postgresql.org
Cc: alvherre@2ndquadrant.com, pryzby@telsasoft.com, tgl@sss.pgh.pa.us, amitlangote09@gmail.com, pgsql-hackers@lists.postgresql.org
Subject: Re: DETACH PARTITION and FOR EACH ROW triggers on partitioned tables
In-Reply-To: <20200419191329.GA32288@alvherre.pgsql>
* 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