Re: [HACKERS] [COMMITTERS] pgsql: Simplify plpgsql's check for simple expressions. - Mailing list pgsql-hackers

From Robert Haas
Subject Re: [HACKERS] [COMMITTERS] pgsql: Simplify plpgsql's check for simple expressions.
Date
Msg-id CA+TgmobV+=2NiD99Z08VAXik7txRRxKMLNVkjZhiJ48ZAp2rfQ@mail.gmail.com
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In response to Re: [HACKERS] [COMMITTERS] pgsql: Simplify plpgsql's check for simple expressions.  (Tom Lane <tgl@sss.pgh.pa.us>)
Responses Re: [HACKERS] [COMMITTERS] pgsql: Simplify plpgsql's check for simple expressions.  (Tom Lane <tgl@sss.pgh.pa.us>)
List pgsql-hackers
On Wed, Aug 16, 2017 at 12:49 PM, Tom Lane <tgl@sss.pgh.pa.us> wrote:
> Robert Haas <robertmhaas@gmail.com> writes:
>> On Wed, Aug 16, 2017 at 11:56 AM, Tom Lane <tgl@sss.pgh.pa.us> wrote:
>>> I can get on board with that statement.  Can you draft a better wording?
>
>> Here is an attempt.  Feel free to edit.
>
> I think s/plan/query/ in the last bit would be better.  Perhaps
>
> +        * However, if force_parallel_mode = on or force_parallel_mode = regress,
> +        * then we impose parallel mode whenever it's safe to do so, even if the
> +        * final plan doesn't use parallelism.  It's not safe to do so if the query
> +        * contains anything parallel-unsafe; parallelModeOK will be false in that
> +        * case.  Otherwise, everything in the query is either parallel-safe or
> +        * parallel-restricted, and in either case it should be OK to impose
> +        * parallel-mode restrictions.  If that ends up breaking something, then
> +        * either some function the user included in the query is incorrectly
> +        * labelled as parallel-safe or parallel-restricted when in reality it's
> +        * parallel-unsafe, or else the query planner itself has a bug.
>          */

Works for me.  I'm happy to phrase this in any way that makes it clear
to you, 'cuz it's already clear to me.  :-)

You want to push something, or should I do it?

-- 
Robert Haas
EnterpriseDB: http://www.enterprisedb.com
The Enterprise PostgreSQL Company



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