<feed xmlns='http://www.w3.org/2005/Atom'>
<title>delta/postgresql.git/src/backend/optimizer, branch master</title>
<subtitle>git.postgresql.org: git/postgresql.git
</subtitle>
<link rel='alternate' type='text/html' href='http://91.123.203.49/cgit/delta/postgresql.git/'/>
<entry>
<title>Track tlist_vinfo.varnullingrels even in non-Assert builds.</title>
<updated>2023-05-17T15:46:15+00:00</updated>
<author>
<name>Tom Lane</name>
<email>tgl@sss.pgh.pa.us</email>
</author>
<published>2023-05-17T15:46:15+00:00</published>
<link rel='alternate' type='text/html' href='http://91.123.203.49/cgit/delta/postgresql.git/commit/?id=69c430626b5eb44825a12e8bc90a59a90c4f5a03'/>
<id>69c430626b5eb44825a12e8bc90a59a90c4f5a03</id>
<content type='text'>
Oversight in commit 867be9c07 (which should get reverted
along with that, if we ever do revert it).  Per buildfarm.
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Oversight in commit 867be9c07 (which should get reverted
along with that, if we ever do revert it).  Per buildfarm.
</pre>
</div>
</content>
</entry>
<entry>
<title>Fix some issues with improper placement of outer join clauses.</title>
<updated>2023-05-17T15:14:04+00:00</updated>
<author>
<name>Tom Lane</name>
<email>tgl@sss.pgh.pa.us</email>
</author>
<published>2023-05-17T15:13:52+00:00</published>
<link rel='alternate' type='text/html' href='http://91.123.203.49/cgit/delta/postgresql.git/commit/?id=9df8f903eb6758be5a19e66cdf77e922e9329c31'/>
<id>9df8f903eb6758be5a19e66cdf77e922e9329c31</id>
<content type='text'>
After applying outer-join identity 3 in the forward direction,
it was possible for the planner to mistakenly apply a qual clause
from above the two outer joins at the now-lower join level.
This can give the wrong answer, since a value that would get nulled
by the now-upper join might not yet be null.

To fix, when we perform such a transformation, consider that the
now-lower join hasn't really completed the outer join it's nominally
responsible for and thus its relid set should not include that OJ's
relid (nor should its output Vars have that nullingrel bit set).
Instead we add those bits when the now-upper join is performed.
The existing rules for qual placement then suffice to prevent
higher qual clauses from dropping below the now-upper join.
There are a few complications from needing to consider transitive
closures in case multiple pushdowns have happened, but all in all
it's not a very complex patch.

This is all new logic (from 2489d76c4) so no need to back-patch.
The added test cases all have the same results as in v15.

Tom Lane and Richard Guo

Discussion: https://postgr.es/m/0b819232-4b50-f245-1c7d-c8c61bf41827@postgrespro.ru
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
After applying outer-join identity 3 in the forward direction,
it was possible for the planner to mistakenly apply a qual clause
from above the two outer joins at the now-lower join level.
This can give the wrong answer, since a value that would get nulled
by the now-upper join might not yet be null.

To fix, when we perform such a transformation, consider that the
now-lower join hasn't really completed the outer join it's nominally
responsible for and thus its relid set should not include that OJ's
relid (nor should its output Vars have that nullingrel bit set).
Instead we add those bits when the now-upper join is performed.
The existing rules for qual placement then suffice to prevent
higher qual clauses from dropping below the now-upper join.
There are a few complications from needing to consider transitive
closures in case multiple pushdowns have happened, but all in all
it's not a very complex patch.

This is all new logic (from 2489d76c4) so no need to back-patch.
The added test cases all have the same results as in v15.

Tom Lane and Richard Guo

Discussion: https://postgr.es/m/0b819232-4b50-f245-1c7d-c8c61bf41827@postgrespro.ru
</pre>
</div>
</content>
</entry>
<entry>
<title>Convert nullingrels match checks from Asserts to test-and-elog.</title>
<updated>2023-05-17T15:14:04+00:00</updated>
<author>
<name>Tom Lane</name>
<email>tgl@sss.pgh.pa.us</email>
</author>
<published>2023-05-17T14:50:35+00:00</published>
<link rel='alternate' type='text/html' href='http://91.123.203.49/cgit/delta/postgresql.git/commit/?id=867be9c0738bef591544d39985f886b7d8e99bf0'/>
<id>867be9c0738bef591544d39985f886b7d8e99bf0</id>
<content type='text'>
It seems like the code that these checks are backstopping may have
a few bugs left in it.  Use a test-and-elog so that the tests are
performed even in non-assert builds, and so that we get something
more informative than "server closed the connection" on failure.

Committed separately with the idea that eventually we'll revert
this.  It might be awhile though.

Discussion: https://postgr.es/m/3014965.1684293045@sss.pgh.pa.us
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
It seems like the code that these checks are backstopping may have
a few bugs left in it.  Use a test-and-elog so that the tests are
performed even in non-assert builds, and so that we get something
more informative than "server closed the connection" on failure.

Committed separately with the idea that eventually we'll revert
this.  It might be awhile though.

Discussion: https://postgr.es/m/3014965.1684293045@sss.pgh.pa.us
</pre>
</div>
</content>
</entry>
<entry>
<title>Add back SQLValueFunction for SQL keywords</title>
<updated>2023-05-17T01:19:17+00:00</updated>
<author>
<name>Michael Paquier</name>
<email>michael@paquier.xyz</email>
</author>
<published>2023-05-17T01:19:17+00:00</published>
<link rel='alternate' type='text/html' href='http://91.123.203.49/cgit/delta/postgresql.git/commit/?id=d8c3106bb60e4f87be595f241e173ba3c2b7aa2c'/>
<id>d8c3106bb60e4f87be595f241e173ba3c2b7aa2c</id>
<content type='text'>
This is equivalent to a revert of f193883 and fb32748, with the addition
that the declaration of the SQLValueFunction node needs to gain a couple
of node_attr for query jumbling.  The performance impact of removing the
function call inlining is proving to be too huge for some workloads
where these are used.  A worst-case test case of involving only simple
SELECT queries with a SQL keyword is proving to lead to a reduction of
10% in TPS via pgbench and prepared queries on a high-end machine.

None of the tests I ran back for this set of changes saw such a huge
gap, but Alexander Lakhin and Andres Freund have found that this can be
noticeable.  Keeping the older performance would mean to do more
inlining in the executor when using COERCE_SQL_SYNTAX for a function
expression, similarly to what SQLValueFunction does.  This requires more
redesign work and there is little time until 16beta1 is released, so for
now reverting the change is the best way forward, bringing back the
previous performance.

Bump catalog version.

Reported-by: Alexander Lakhin
Discussion: https://postgr.es/m/b32bed1b-0746-9b20-1472-4bdc9ca66d52@gmail.com
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
This is equivalent to a revert of f193883 and fb32748, with the addition
that the declaration of the SQLValueFunction node needs to gain a couple
of node_attr for query jumbling.  The performance impact of removing the
function call inlining is proving to be too huge for some workloads
where these are used.  A worst-case test case of involving only simple
SELECT queries with a SQL keyword is proving to lead to a reduction of
10% in TPS via pgbench and prepared queries on a high-end machine.

None of the tests I ran back for this set of changes saw such a huge
gap, but Alexander Lakhin and Andres Freund have found that this can be
noticeable.  Keeping the older performance would mean to do more
inlining in the executor when using COERCE_SQL_SYNTAX for a function
expression, similarly to what SQLValueFunction does.  This requires more
redesign work and there is little time until 16beta1 is released, so for
now reverting the change is the best way forward, bringing back the
previous performance.

Bump catalog version.

Reported-by: Alexander Lakhin
Discussion: https://postgr.es/m/b32bed1b-0746-9b20-1472-4bdc9ca66d52@gmail.com
</pre>
</div>
</content>
</entry>
<entry>
<title>Undo faulty attempt at not relying on RINFO_IS_PUSHED_DOWN.</title>
<updated>2023-05-11T17:44:25+00:00</updated>
<author>
<name>Tom Lane</name>
<email>tgl@sss.pgh.pa.us</email>
</author>
<published>2023-05-11T17:44:25+00:00</published>
<link rel='alternate' type='text/html' href='http://91.123.203.49/cgit/delta/postgresql.git/commit/?id=c8b881d21fd8e0214bc43280d6231cc2c6ef55ef'/>
<id>c8b881d21fd8e0214bc43280d6231cc2c6ef55ef</id>
<content type='text'>
I've had a bee in my bonnet for some time about getting rid of
RestrictInfo.is_pushed_down, because it's squishily defined and
requires not-inexpensive extra tests to use (cf RINFO_IS_PUSHED_DOWN).
In commit 2489d76c4, I tried to make remove_rel_from_query() not
depend on that macro; but the replacement test is buggy,
as exposed by a report from Rushabh Lathia and Robert Haas.
That change was pretty incidental to the main goal of 2489d76c4,
so let's just revert it for now.  (Getting rid of is_pushed_down
is still far away, anyway.)

Discussion: https://postgr.es/m/CA+TgmoYco=hmg+iX1CW9Y1_CzNoSL81J03wUG-d2_3=rue+L2A@mail.gmail.com
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
I've had a bee in my bonnet for some time about getting rid of
RestrictInfo.is_pushed_down, because it's squishily defined and
requires not-inexpensive extra tests to use (cf RINFO_IS_PUSHED_DOWN).
In commit 2489d76c4, I tried to make remove_rel_from_query() not
depend on that macro; but the replacement test is buggy,
as exposed by a report from Rushabh Lathia and Robert Haas.
That change was pretty incidental to the main goal of 2489d76c4,
so let's just revert it for now.  (Getting rid of is_pushed_down
is still far away, anyway.)

Discussion: https://postgr.es/m/CA+TgmoYco=hmg+iX1CW9Y1_CzNoSL81J03wUG-d2_3=rue+L2A@mail.gmail.com
</pre>
</div>
</content>
</entry>
<entry>
<title>Handle RLS dependencies in inlined set-returning functions properly.</title>
<updated>2023-05-08T14:12:44+00:00</updated>
<author>
<name>Tom Lane</name>
<email>tgl@sss.pgh.pa.us</email>
</author>
<published>2023-05-08T14:12:44+00:00</published>
<link rel='alternate' type='text/html' href='http://91.123.203.49/cgit/delta/postgresql.git/commit/?id=ca73753b090c33bc69ce299b4d7fff891a77b8ad'/>
<id>ca73753b090c33bc69ce299b4d7fff891a77b8ad</id>
<content type='text'>
If an SRF in the FROM clause references a table having row-level
security policies, and we inline that SRF into the calling query,
we neglected to mark the plan as potentially dependent on which
role is executing it.  This could lead to later executions in the
same session returning or hiding rows that should have been hidden
or returned instead.

Our thanks to Wolfgang Walther for reporting this problem.

Stephen Frost and Tom Lane

Security: CVE-2023-2455
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
If an SRF in the FROM clause references a table having row-level
security policies, and we inline that SRF into the calling query,
we neglected to mark the plan as potentially dependent on which
role is executing it.  This could lead to later executions in the
same session returning or hiding rows that should have been hidden
or returned instead.

Our thanks to Wolfgang Walther for reporting this problem.

Stephen Frost and Tom Lane

Security: CVE-2023-2455
</pre>
</div>
</content>
</entry>
<entry>
<title>Revert "Move PartitionPruneInfo out of plan nodes into PlannedStmt"</title>
<updated>2023-05-04T10:09:59+00:00</updated>
<author>
<name>Alvaro Herrera</name>
<email>alvherre@alvh.no-ip.org</email>
</author>
<published>2023-05-04T10:09:59+00:00</published>
<link rel='alternate' type='text/html' href='http://91.123.203.49/cgit/delta/postgresql.git/commit/?id=5472743d9e8583638a897b47558066167cc14583'/>
<id>5472743d9e8583638a897b47558066167cc14583</id>
<content type='text'>
This reverts commit ec386948948c and its fixup 589bb816499e.

This change was intended to support query planning avoiding acquisition
of locks on partitions that were going to be pruned; however, the
overall project took a different direction at [1] and this bit is no
longer needed.  Put things back the way they were as agreed in [2], to
avoid unnecessary complexity.

Discussion: [1] https://postgr.es/m/4191508.1674157166@sss.pgh.pa.us
Discussion: [2] https://postgr.es/m/20230502175409.kcoirxczpdha26wt@alvherre.pgsql
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
This reverts commit ec386948948c and its fixup 589bb816499e.

This change was intended to support query planning avoiding acquisition
of locks on partitions that were going to be pruned; however, the
overall project took a different direction at [1] and this bit is no
longer needed.  Put things back the way they were as agreed in [2], to
avoid unnecessary complexity.

Discussion: [1] https://postgr.es/m/4191508.1674157166@sss.pgh.pa.us
Discussion: [2] https://postgr.es/m/20230502175409.kcoirxczpdha26wt@alvherre.pgsql
</pre>
</div>
</content>
</entry>
<entry>
<title>Fix typos in comments</title>
<updated>2023-05-02T03:23:08+00:00</updated>
<author>
<name>Michael Paquier</name>
<email>michael@paquier.xyz</email>
</author>
<published>2023-05-02T03:23:08+00:00</published>
<link rel='alternate' type='text/html' href='http://91.123.203.49/cgit/delta/postgresql.git/commit/?id=8961cb9a0315fa23458587b3df547ca8d8e00f85'/>
<id>8961cb9a0315fa23458587b3df547ca8d8e00f85</id>
<content type='text'>
The changes done in this commit impact comments with no direct
user-visible changes, with fixes for incorrect function, variable or
structure names.

Author: Alexander Lakhin
Discussion: https://postgr.es/m/e8c38840-596a-83d6-bd8d-cebc51111572@gmail.com
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
The changes done in this commit impact comments with no direct
user-visible changes, with fixes for incorrect function, variable or
structure names.

Author: Alexander Lakhin
Discussion: https://postgr.es/m/e8c38840-596a-83d6-bd8d-cebc51111572@gmail.com
</pre>
</div>
</content>
</entry>
<entry>
<title>Fix various typos and incorrect/outdated name references</title>
<updated>2023-04-19T01:50:33+00:00</updated>
<author>
<name>David Rowley</name>
<email>drowley@postgresql.org</email>
</author>
<published>2023-04-19T01:50:33+00:00</published>
<link rel='alternate' type='text/html' href='http://91.123.203.49/cgit/delta/postgresql.git/commit/?id=3f58a4e2960a9509036b7d94beab64a747dc59dc'/>
<id>3f58a4e2960a9509036b7d94beab64a747dc59dc</id>
<content type='text'>
Author: Alexander Lakhin
Discussion: https://postgr.es/m/699beab4-a6ca-92c9-f152-f559caf6dc25@gmail.com
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Author: Alexander Lakhin
Discussion: https://postgr.es/m/699beab4-a6ca-92c9-f152-f559caf6dc25@gmail.com
</pre>
</div>
</content>
</entry>
<entry>
<title>Fix some typos and some incorrectly duplicated words</title>
<updated>2023-04-18T02:03:49+00:00</updated>
<author>
<name>David Rowley</name>
<email>drowley@postgresql.org</email>
</author>
<published>2023-04-18T02:03:30+00:00</published>
<link rel='alternate' type='text/html' href='http://91.123.203.49/cgit/delta/postgresql.git/commit/?id=eef231e8161eb8031a928fe48134ef25ab81fe5e'/>
<id>eef231e8161eb8031a928fe48134ef25ab81fe5e</id>
<content type='text'>
Author: Justin Pryzby
Reviewed-by: David Rowley
Discussion: https://postgr.es/m/ZD3D1QxoccnN8A1V@telsasoft.com
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Author: Justin Pryzby
Reviewed-by: David Rowley
Discussion: https://postgr.es/m/ZD3D1QxoccnN8A1V@telsasoft.com
</pre>
</div>
</content>
</entry>
</feed>
