Re: Aggregate not using BRIN index on timestamp - Mailing list pgsql-general

From Alvaro Herrera
Subject Re: Aggregate not using BRIN index on timestamp
Date
Msg-id 20190805172717.GA10185@alvherre.pgsql
Whole thread Raw
In response to Re: Aggregate not using BRIN index on timestamp  (Tom Lane <tgl@sss.pgh.pa.us>)
List pgsql-general
On 2019-Aug-05, Tom Lane wrote:

> FWIW, I suspect the hard part would be dealing with cases where the
> extremal ranges (according to the index) contain no live tuples
> (according to the query's snapshot).  The btree case handles the
> invisible-tuples problem by continuing a scan started at the index
> endpoint until it finds a visible tuple --- which, in the worst case,
> can take a long time.  It's not obvious to me what you'd do with
> BRIN.

Hmm, yeah, that's a tough problem -- hadn't thought about that.

-- 
Álvaro Herrera                https://www.2ndQuadrant.com/
PostgreSQL Development, 24x7 Support, Remote DBA, Training & Services



pgsql-general by date:

Previous
From: Tom Lane
Date:
Subject: Re: Aggregate not using BRIN index on timestamp
Next
From: Michael Lewis
Date:
Subject: Re: How to check if a field exists in NEW in trigger