Postgres Pro
Downloads
Home   >   mailing lists

Re: short circuit suggestion in find_hash_columns() - Mailing list pgsql-hackers

From David Rowley
Subject Re: short circuit suggestion in find_hash_columns()
Date
Msg-id CAApHDvqSCvJrc0XQcuqkBFkTue=oKVeDCqBib3DOwd6FguyCcA@mail.gmail.com
Whole thread Raw
In response to short circuit suggestion in find_hash_columns()  (Zhihong Yu <zyu@yugabyte.com>)
Responses Re: short circuit suggestion in find_hash_columns()  (Zhihong Yu <zyu@yugabyte.com>)
List pgsql-hackers
Tree view 
On Sat, 10 Jul 2021 at 03:15, Zhihong Yu <zyu@yugabyte.com> wrote:
> I was looking at find_hash_columns() in nodeAgg.c
>
> It seems the first loop tries to determine the max column number needed, along with whether all columns are needed.
>
> The loop can be re-written as shown in the patch.

This runs during ExecInitAgg().  Do you have a test case where you're
seeing any performance gains from this change?

David

pgsql-hackers by date:

Previous
From: David Rowley
Date:
Subject: Re: Record a Bitmapset of non-pruned partitions
Next
From: David Rowley
Date:
Subject: Re: enable_resultcache confusion