Re: Physical append-only tables

On Thu, Nov 24, 2016 at 10:13:30AM +0100, Magnus Hagander wrote:
> On Thu, Nov 24, 2016 at 2:26 AM, Bruce Momjian <bruce@momjian.us> wrote:
> 
>     On Mon, Nov 14, 2016 at 08:43:12PM +0000, Greg Stark wrote:
>     > That said, I don't think the "maintain clustering a bit better using
>     > BRIN" is a bad idea. It's just the bit about turning a table
>     > append-only to deal with update-once data that I think is overreach.
> 
>     What if we used BRIN to find heap pages where the new row was in the
>     page BRIN min/max range, and the heap page had free space.  Only if that
>     fails do we put is somewhere else in the heap.
> 
> 
> That would certainly be useful. You'd have to figure out what to do in the case
> of multiple conflicting BRIN indexes (which you shouldn't have in the first
> place, but that won't keep people from having them), but other than that it
> would be quite good I think. 

This idea is only possible because the BRIN index is so small and easy
to scan, i.e. this wouldn't work for a btree index.

--  Bruce Momjian  <bruce@momjian.us>        http://momjian.us EnterpriseDB
http://enterprisedb.com

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