Reply-To: jesper.pedersen@redhat.com
Subject: Re: Index Skip Scan
To: Stephen Frost <sfrost@snowman.net>
Cc: Thomas Munro <thomas.munro@enterprisedb.com>,
 Bhushan Uparkar <bhushan.uparkar@gmail.com>,
 pgsql-hackers <pgsql-hackers@postgresql.org>,
 Alexander Korotkov <a.korotkov@postgrespro.ru>
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 <20180816183602.GT3326@tamriel.snowman.net>
From: Jesper Pedersen <jesper.pedersen@redhat.com>
Organization: Red Hat
Message-ID: <c07bc929-26e2-27a9-adcb-ea12a735037a@redhat.com>
Date: Thu, 16 Aug 2018 14:50:34 -0400
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Hi Stephen,

On 08/16/2018 02:36 PM, Stephen Frost wrote:
>> Yeah, I'm hoping that a Committer can provide some feedback on the direction
>> that this patch needs to take.
> 
> Thomas is one these days. :)
>

I know :)  However, there are some open questions from Thomas' original 
submission that still needs to be ironed out.

> At least on first glance, that indexam seems to make sense to me, but
> I've not spent a lot of time thinking about it.  Might be interesting to
> ask Peter G about it though.
> 

Yes, or Anastasia who also have done a lot of work on nbtree/.

>> One thing to consider is the pluggable storage patch, which is a lot more
>> important than this patch. I don't want this patch to get in the way of that
>> work, so it may have to wait a bit in order to see any new potential
>> requirements.
> 
> Not sure where this came from, but I don't think it's particularly good
> to be suggesting that one feature is more important than another or that
> we need to have one wait for another as this seems to imply.  I'd
> certainly really like to see PG finally have skipping scans, for one
> thing, and it seems like with some effort that might be able to happen
> for v12.  I'm not convinced that we're going to get pluggable storage to
> happen in v12 and I don't really agree with recommending that people
> hold off on making improvements to things because it's coming.
> 

My point was that I know this patch needs work, so any feedback that get 
it closer to a solution will help.

Pluggable storage may / may not add new requirements, but it is up to 
the people working on that, some of which are Committers, to take time 
"off" to provide feedback for this patch in order steer me in right 
direction.

Work can happen in parallel, and I'm definitely not recommending that 
people hold off on any patches that they want to provide feedback for, 
or submit for a CommitFest.

Best regards,
  Jesper