Re: Small run-time pruning doc fix

From: Peter Eisentraut <peter(dot)eisentraut(at)2ndquadrant(dot)com>
To: David Rowley <david(dot)rowley(at)2ndquadrant(dot)com>, PostgreSQL Hackers <pgsql-hackers(at)lists(dot)postgresql(dot)org>
Subject: Re: Small run-time pruning doc fix
Date: 2018-11-02 07:30:24
Message-ID: 9e0a4103-883e-b327-c2fb-20c98061dcff@2ndquadrant.com
Views: Raw Message | Whole Thread | Download mbox | Resend email
Thread:
Lists: pgsql-hackers

On 08/10/2018 10:22, David Rowley wrote:
> Before 5220bb7533f a note in ddl.sgml used to mention that run-time
> pruning was only implemented for Append. When we got MergeAppend
> support the commit updated this to mention MergeAppend is supported
> too. This is slightly weird as it's not all that obvious what exactly
> isn't supported when we mention:
>
> <para>
> Both of these behaviors are likely to be changed in a future release
> of <productname>PostgreSQL</productname>.
> </para>
>
> The attached patch updates this to mention that ModifyTable is
> unsupported which I think makes the above fragment make sense again.

<para>
- Execution-time partition pruning currently occurs for the
+ Execution-time partition pruning currently only occurs for the
<literal>Append</literal> and <literal>MergeAppend</literal> node
types.
+ It is not yet implemented for the <literal>ModifyTable</literal> node
+ type.
</para>

Isn't this implied by the preceding paragraph

Currently, pruning of partitions during the planning of an UPDATE or
DELETE command is implemented using the constraint exclusion method

?

Also, could there be other node types that could benefit from partition
pruning that are not implemented yet? Not sure we want to mention all
of them.

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

In response to

Responses

Browse pgsql-hackers by date

  From Date Subject
Next Message Fabien COELHO 2018-11-02 07:35:29 Re: pgbench doc fix
Previous Message Fabien COELHO 2018-11-02 07:17:51 Re: CF app feature request