Date: Fri, 23 Nov 2018 17:39:14 +0100
From: David Fetter <david@fetter.org>
To: Petr Jelinek <petr.jelinek@2ndquadrant.com>
Cc: Euler Taveira <euler@timbira.com.br>,
	pgsql-hackers <pgsql-hackers@postgresql.org>,
	Suzuki Hironobu <hironobu@interdb.jp>
Subject: Re: row filtering for logical replication
Message-ID: <20181123163913.GK958@fetter.org>
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On Fri, Nov 23, 2018 at 12:03:27AM +0100, Petr Jelinek wrote:
> On 01/11/2018 01:29, Euler Taveira wrote:
> > Em qua, 28 de fev de 2018 às 20:03, Euler Taveira
> > <euler@timbira.com.br> escreveu:
> >> The attached patches add support for filtering rows in the publisher.
> >>
> > I rebased the patch. I added row filtering for initial
> > synchronization, pg_dump support and psql support. 0001 removes unused
> > code. 0002 reduces memory use. 0003 passes only structure member that
> > is used in create_estate_for_relation. 0004 reuses a parser node for
> > row filtering. 0005 is the feature. 0006 prints WHERE expression in
> > psql. 0007 adds pg_dump support. 0008 is only for debug purposes (I'm
> > not sure some of these messages will be part of the final patch).
> > 0001, 0002, 0003 and 0008 are not mandatory for this feature.
> 
> Hi,
> 
> I think there are two main topics that still need to be discussed about
> this patch.
> 
> Firstly, I am not sure if it's wise to allow UDFs in the filter clause
> for the table. The reason for that is that we can't record all necessary
> dependencies there because the functions are black box for parser.

Some UDFs are not a black box for the parser, namely ones written in
SQL. Would it make sense at least not to foreclose the non-(black box)
option?

Best,
David.
-- 
David Fetter <david(at)fetter(dot)org> http://fetter.org/
Phone: +1 415 235 3778

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