Re: [POC]Enable tuple change partition caused by BEFORE TRIGGER

On 2020-Aug-27, Ashutosh Bapat wrote:

> On Wed, 26 Aug 2020 at 22:47, Alvaro Herrera <alvherre(at)2ndquadrant(dot)com>
> wrote:

> > But I'm not 100% about running the BEFORE triggers. Maybe
> > one way to address this is to check whether the BEFORE triggers in the
> > new target partition are clones; if so then they would have run in the
> > original target partition and so must not be run, but otherwise they
> > have to.
>
> This will work as long as the two BEFORE ROW triggers have the same effect.
> Consider two situations resulting in inserting identical rows 1. row that
> the before row trigger has redirected to a new partition, say part2 2. a
> row inserted directly into the part2 - if both these rows are identical
> before the BEFORE ROW triggers have been applied, they should remain
> identical while inserting into part2. Any divergence might be problematic
> for the application.

Well, that's why I talk about the trigger being "clones" -- with that
term, I mean that their definitions have been inherited from a
definition in some ancestor partitioned table, and so they must be
identical in the partitions.

--
Álvaro Herrera https://www.2ndQuadrant.com/
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