Subject: Re: Logical replication and multimaster
To: David Fetter <david@fetter.org>, Craig Ringer <craig@2ndquadrant.com>, Jon
 Erdman <jon@progressivepractice.com>
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CC: Robert Haas <robertmhaas@gmail.com>, Andres Freund <andres@anarazel.de>,
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From: Jim Nasby <Jim.Nasby@BlueTreble.com>
Message-ID: <5670DF24.7090101@BlueTreble.com>
Date: Tue, 15 Dec 2015 21:48:52 -0600
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On 12/13/15 7:37 AM, David Fetter wrote:
> As I understand it, pushing these into a library has been proposed but
> not rejected.  That it hasn't happened yet is mostly about the lack of
> tuits (the round ones) to rewrite the functionality as libraries and
> refactor pg_dump/pg_restore to use only calls to same.  As usual, it's
> less about writing the code and more about the enormous amount of
> testing any such a refactor would entail.

My understanding as well. IIRC Jon Erdman brought this question up a 
couple years ago and the response was "It'd probably be accepted, it's 
just that no one has done the work."

> I believe that refactoring much of pg_dump's functionality for the
> current version of the server into SQL-accessible functions and making
> pg_dump use only those functions is achievable with available
> resources.
>
> Such a refactor need not be all-or-nothing.  For example, the
> dependency resolution stuff is a first step that appears to be worth
> doing by itself even if the effort then pauses, possibly for some
> time.

If someone wanted to spend time on this, I suspect it'd be worth looking 
at how bad some of the backward compatibility issues would be if done in 
the server. Maybe they wouldn't be that bad. I suspect the audience for 
this code would be much larger if it was in the server as opposed to a C 
library.
-- 
Jim Nasby, Data Architect, Blue Treble Consulting, Austin TX
Experts in Analytics, Data Architecture and PostgreSQL
Data in Trouble? Get it in Treble! http://BlueTreble.com


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