Re: Multi-column distinctness. - Mailing list pgsql-hackers

From Simon Riggs
Subject Re: Multi-column distinctness.
Date
Msg-id CANP8+j+E5V3PEtkGJ=LFVpE10nVY8+7nC86JGThX7vgRwX47vw@mail.gmail.com
Whole thread Raw
In response to Re: Multi-column distinctness.  (Tomas Vondra <tomas.vondra@2ndquadrant.com>)
Responses Re: Multi-column distinctness.  (Tomas Vondra <tomas.vondra@2ndquadrant.com>)
List pgsql-hackers
On 19 October 2015 at 20:16, Tomas Vondra <tomas.vondra@2ndquadrant.com> wrote:
Hello Kyotaro-san,

On 09/11/2015 06:58 PM, Tomas Vondra wrote:
>
Maybe the best solution is to abandon the ALTER TABLE approach
entirely, and instead invent a new set of commands

   CREATE STATISTICS
   DROP STATISTICS

(ALTER STATISTICS seems a bit excessive at this point).

Another thing is that perhaps we should add names for statistics,
just like we do for constraints, for example. Otherwise the DROP
STATISTICS handling is rather awkward - for example if the user
creates stats twice by mistake, he's unable to drop just one of them.

Do you think this modified syntax makes sense? I'll have time to hack on this over the next few days.

Koyotaro's changes to force COLUMN to be required won't get through.

ISTM that we could use COLLECT STATISTICS instead of ADD STATISTICS, and use REMOVE STATISTICS instead of DROP STATISTICS. That way we can use ALTER TABLE rather than inventing a new command. 5 minute change...

Unless there is some better reason for a whole new command? 

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

pgsql-hackers by date:

Previous
From: Beena Emerson
Date:
Subject: Re: Support for N synchronous standby servers - take 2
Next
From: Alexander Korotkov
Date:
Subject: Re: PoC: Partial sort