Re: WIP: generalized index constraints

Simon Riggs <simon@2ndquadrant.com>

From: Simon Riggs <simon@2ndQuadrant.com>
To: Jeff Davis <pgsql@j-davis.com>
Cc: pgsql-hackers@postgresql.org
Date: 2009-07-06T10:56:41Z
Lists: pgsql-hackers
On Sun, 2009-07-05 at 17:28 -0700, Jeff Davis wrote:
> This is a follow up to my old proposal here:
> 
> http://archives.postgresql.org/pgsql-hackers/2008-06/msg00404.php
> 

> Any input is appreciated (design problems, implementation, language
> ideas, or anything else). I'd like to get it into shape for the July
> 15 commitfest if no major problems are found.

I was concerned that your definition of concurrently inserted didn't
seem to match the size of the shared memory array required.

How will you cope with a large COPY? Surely there can be more than one
concurrent insert from any backend?


It would be useful to see a real example of what this can be used for.


I think it will be useful to separate the concepts of a constraint from
the concept of an index. It seems possible to have a UNIQUE constraint
that doesn't help at all in locating rows, just in proving that the rows
are unique.

-- 
 Simon Riggs           www.2ndQuadrant.com
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