Subject: Re: FOR EACH ROW triggers on partitioned tables
References: <20180214212624.hm7of76flesodamf@alvherre.pgsql>
From: Amit Langote <Langote_Amit_f8@lab.ntt.co.jp>
Message-ID: <77d52cfc-76d4-91ea-da90-ff2dc2db6f6b@lab.ntt.co.jp>
Date: Thu, 15 Feb 2018 16:25:54 +0900
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To: Alvaro Herrera <alvherre@alvh.no-ip.org>,
        Robert Haas <robertmhaas@gmail.com>
Cc: Peter Eisentraut <peter.eisentraut@2ndquadrant.com>,
        Pg Hackers <pgsql-hackers@postgresql.org>,
        Simon Riggs <simon@2ndquadrant.com>
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On 2018/02/15 6:26, Alvaro Herrera wrote:
> Another option is to rethink this feature from the ground up: instead of
> cloning catalog rows for each children, maybe we should have the trigger
> lookup code, when running DML on the child relation (the partition),
> obtain trigger entries not only for the child relation itself but also
> for its parents recursively -- so triggers defined in the parent are
> fired for the partitions, too.  I'm not sure what implications this has
> for constraint triggers.
>
> The behavior should be the same, except that you cannot modify the
> trigger (firing conditions, etc) on the partition individually -- it
> works at the level of the whole partitioned table instead.

Do you mean to fire these triggers only if the parent table (not a child
table/partition) is addressed in the DML, right?  If the table directly
addressed in the DML is a partition whose parent has a row-level trigger,
then that trigger should not get fired I suppose.

Thanks,
Amit