Re: [HACKERS] BRIN de-summarize ranges - Mailing list pgsql-hackers

From Simon Riggs
Subject Re: [HACKERS] BRIN de-summarize ranges
Date
Msg-id CANP8+jK9+yPZOdzxh6D4xEViyeVTZxuGMfCx8YLjzHzh2POAfw@mail.gmail.com
Whole thread Raw
In response to [HACKERS] BRIN de-summarize ranges  (Alvaro Herrera <alvherre@2ndquadrant.com>)
Responses Re: [HACKERS] BRIN de-summarize ranges  ("Seki, Eiji" <seki.eiji@jp.fujitsu.com>)
List pgsql-hackers
On 28 February 2017 at 12:56, Alvaro Herrera <alvherre@2ndquadrant.com> wrote:

> Here's a small patch to make a BRIN page range unsummarized.  This is
> useful if data has been deleted, and the heap pages are now used for
> completely different data.

We currently have a manual interface for summarize new values, so it
makes sense to include a manual interface for desummarize also. Since
this adds desummarize_range it would make sense to expose
summarize_range also.

I'd prefer if we had a way to know when the summary is no longer
useful and to do this automatically, but we'd need more info and
research to work out how to do that, so we can only do it this way at
present.

Other than that the patch looks fairly straightforward, so adding a
few tests will be all we need here.

Plus function docs. I'm on the hook to write brin docs anyway, so no
more needed here.

-- 
Simon Riggs                http://www.2ndQuadrant.com/
PostgreSQL Development, 24x7 Support, Remote DBA, Training & Services



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