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* Re: [COMMITTERS] pgsql: If we expect a hash join to be performed in multiple batches,
@ 2009-04-02 17:11 Simon Riggs <simon@2ndQuadrant.com>
2009-04-02 19:49 ` Re: [COMMITTERS] pgsql: If we expect a hash join to be performed in multiple batches, Tom Lane <tgl@sss.pgh.pa.us>
0 siblings, 1 reply; 4+ messages in thread
From: Simon Riggs @ 2009-04-02 17:11 UTC (permalink / raw)
To: Tom Lane <tgl@postgresql.org>; +Cc: pgsql-hackers@postgresql.org
On Thu, 2009-03-26 at 17:15 +0000, Tom Lane wrote:
> Log Message:
> -----------
> If we expect a hash join to be performed in multiple batches, suppress
> "physical tlist" optimization on the outer relation (ie, force a projection
> step to occur in its scan). This avoids storing useless column values when
> the outer relation's tuples are written to temporary batch files.
Can we add "batches=N" to the EXPLAIN output for Hash and/or Hash Join?
--
Simon Riggs www.2ndQuadrant.com
PostgreSQL Training, Services and Support
^ permalink raw reply [nested|flat] 4+ messages in thread
* Re: [COMMITTERS] pgsql: If we expect a hash join to be performed in multiple batches,
2009-04-02 17:11 Re: [COMMITTERS] pgsql: If we expect a hash join to be performed in multiple batches, Simon Riggs <simon@2ndQuadrant.com>
@ 2009-04-02 19:49 ` Tom Lane <tgl@sss.pgh.pa.us>
2009-04-02 20:32 ` Re: [COMMITTERS] pgsql: If we expect a hash join to be performed in multiple batches, Simon Riggs <simon@2ndQuadrant.com>
0 siblings, 1 reply; 4+ messages in thread
From: Tom Lane @ 2009-04-02 19:49 UTC (permalink / raw)
To: Simon Riggs <simon@2ndquadrant.com>; +Cc: pgsql-hackers@postgresql.org
Simon Riggs <simon@2ndquadrant.com> writes:
> Can we add "batches=N" to the EXPLAIN output for Hash and/or Hash Join?
Are you talking about expected batches, or actual batches? If the
former, would it be sufficient to distinguish "1" from "more than 1"?
If so, maybe changing the node title to "Batched Hash" would do.
regards, tom lane
^ permalink raw reply [nested|flat] 4+ messages in thread
* Re: [COMMITTERS] pgsql: If we expect a hash join to be performed in multiple batches,
2009-04-02 17:11 Re: [COMMITTERS] pgsql: If we expect a hash join to be performed in multiple batches, Simon Riggs <simon@2ndQuadrant.com>
2009-04-02 19:49 ` Re: [COMMITTERS] pgsql: If we expect a hash join to be performed in multiple batches, Tom Lane <tgl@sss.pgh.pa.us>
@ 2009-04-02 20:32 ` Simon Riggs <simon@2ndQuadrant.com>
0 siblings, 0 replies; 4+ messages in thread
From: Simon Riggs @ 2009-04-02 20:32 UTC (permalink / raw)
To: Tom Lane <tgl@sss.pgh.pa.us>; +Cc: pgsql-hackers@postgresql.org
On Thu, 2009-04-02 at 15:49 -0400, Tom Lane wrote:
> Simon Riggs <simon@2ndquadrant.com> writes:
> > Can we add "batches=N" to the EXPLAIN output for Hash and/or Hash Join?
>
> Are you talking about expected batches, or actual batches?
Expected batches for EXPLAIN, both for EXPLAIN ANALYZE.
> If the
> former, would it be sufficient to distinguish "1" from "more than 1"?
> If so, maybe changing the node title to "Batched Hash" would do.
Hmmm, knowing the number of batches is beneficial since it helps you to
calculate the required memory to get best performance.
--
Simon Riggs www.2ndQuadrant.com
PostgreSQL Training, Services and Support
^ permalink raw reply [nested|flat] 4+ messages in thread
* pgsql: Inline basic UTF-8 functions.
@ 2024-03-20 16:47 Jeff Davis <jdavis@postgresql.org>
0 siblings, 0 replies; 4+ messages in thread
From: Jeff Davis @ 2024-03-20 16:47 UTC (permalink / raw)
To: pgsql-committers@lists.postgresql.org
Inline basic UTF-8 functions.
Shows a measurable speedup when processing UTF-8 data, such as with
the new builtin collation provider.
Discussion: https://postgr.es/m/163f4e2190cdf67f67016044e503c5004547e5a9.camel@j-davis.com
Reviewed-by: Peter Eisentraut
Branch
------
master
Details
-------
https://git.postgresql.org/pg/commitdiff/9acae56ce0b0812f3e940cf1f87e73e8d5784e78
Modified Files
--------------
src/common/wchar.c | 61 -----------------------------------------------
src/include/mb/pg_wchar.h | 61 +++++++++++++++++++++++++++++++++++++++++++++++
2 files changed, 61 insertions(+), 61 deletions(-)
^ permalink raw reply [nested|flat] 4+ messages in thread
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2009-04-02 17:11 Re: [COMMITTERS] pgsql: If we expect a hash join to be performed in multiple batches, Simon Riggs <simon@2ndQuadrant.com>
2009-04-02 19:49 ` Tom Lane <tgl@sss.pgh.pa.us>
2009-04-02 20:32 ` Simon Riggs <simon@2ndQuadrant.com>
2024-03-20 16:47 pgsql: Inline basic UTF-8 functions. Jeff Davis <jdavis@postgresql.org>
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