I wrote:
> Andrew Gierth writes:
>> So what I think we need to do here is to forbid inlining if (a) the
>> refcount is greater than 1 and (b) the CTE in question contains,
>> recursively anywhere inside its rtable or the rtables of any of its
>> nested CTEs, a "self_reference" RTE.
> That's kind
> On 2018-08-08 16:55:22 +1200, Thomas Munro wrote:
>> On Fri, Jul 27, 2018 at 8:10 PM, David Fetter wrote:
>> > On Fri, Jul 27, 2018 at 02:55:26PM +1200, Thomas Munro wrote:
>> >> On Thu, Jul 26, 2018 at 7:14 AM, David Fetter wrote:
>> >> > Please find attached the next version, which passes 'ma
> "Tom" == Tom Lane writes:
>> I also thought about that. But what I thought about it on reflection
>> was: if the user explicitly wrote NOT MATERIALIZED, then we should
>> assume they mean it.
Tom> Ah, but the example I gave also had MATERIALIZED on the inner WITH.
Tom> Why should the
Andrew Gierth writes:
> "Tom" == Tom Lane writes:
> Tom> Also, I thought of a somewhat-related scenario that the code isn't
> Tom> accounting for: you can break the restrictions about single
> Tom> evaluation with nested WITHs, like
> I also thought about that. But what I thought about it on
> "Tom" == Tom Lane writes:
Tom> Also, I thought of a somewhat-related scenario that the code isn't
Tom> accounting for: you can break the restrictions about single
Tom> evaluation with nested WITHs, like
I also thought about that. But what I thought about it on reflection
was: if the use
Andrew Gierth writes:
> Here, uncommenting that NOT actually changes the result, from 22 rows to
> 4 rows, because we end up generating multiple worktable scans and the
> recursion logic is not set up to handle that.
Ugh.
> So what I think we need to do here is to forbid inlining if (a) the
> re
So it turns out there's another case we have to check for, as reported
on IRC by Yaroslav Schekin (though I've simplified his query a little):
WITH RECURSIVE
x(a) AS ((VALUES ('a'),('b'))
UNION ALL
(WITH
z AS /*NOT*/ MATERIALIZED (SELECT a FROM x)
On 16/02/2019 22.14, Tom Lane wrote:
I was expecting more controversy ... pushed that way.
Thanks! And thanks to everyone else who worked on this patch!
Andreas
On 2/16/19 10:14 PM, Tom Lane wrote:
> Tomas Vondra writes:
>> On 2/14/19 8:22 PM, Merlin Moncure wrote:
>>> On Thu, Feb 14, 2019 at 10:02 AM Alvaro Herrera
>>> wrote:
On 2019-Feb-14, Peter Eisentraut wrote:
> If we're not really planning to add any more options, I'd register a
>
On 2/16/19 4:14 PM, Tom Lane wrote:
> Tomas Vondra writes:
>> On 2/14/19 8:22 PM, Merlin Moncure wrote:
>>> On Thu, Feb 14, 2019 at 10:02 AM Alvaro Herrera
>>> wrote:
On 2019-Feb-14, Peter Eisentraut wrote:
> If we're not really planning to add any more options, I'd register a
> ligh
Tomas Vondra writes:
> On 2/14/19 8:22 PM, Merlin Moncure wrote:
>> On Thu, Feb 14, 2019 at 10:02 AM Alvaro Herrera
>> wrote:
>>> On 2019-Feb-14, Peter Eisentraut wrote:
If we're not really planning to add any more options, I'd register a
light vote for MATERIALIZED. It reads easier, s
On 2/14/19 8:22 PM, Merlin Moncure wrote:
> On Thu, Feb 14, 2019 at 10:02 AM Alvaro Herrera
> wrote:
>>
>> On 2019-Feb-14, Peter Eisentraut wrote:
>>
>>> On 14/02/2019 16:11, Tom Lane wrote:
... so, have we beaten this topic to death yet? Can we make a decision?
Personally, I'd be
On 14/02/2019 16.11, Tom Lane wrote:
... so, have we beaten this topic to death yet? Can we make a decision?
Personally, I'd be happy with either of the last two patch versions
I posted (that is, either AS [[NOT] MATERIALIZED] or
AS [MATERIALIZE [ON|OFF]] syntax). But we gotta pick something.
On Thu, Feb 14, 2019 at 04:25:27PM +0100, Peter Eisentraut wrote:
> On 06/02/2019 10:00, Bruce Momjian wrote:
> > I think "materialize" is the right word since "materialized" would be
> > past tense.
>
> It's an adjective. The sentence is, "with foo as the materialized
> $query, do the $main_quer
On Thu, Feb 14, 2019 at 10:02 AM Alvaro Herrera
wrote:
>
> On 2019-Feb-14, Peter Eisentraut wrote:
>
> > On 14/02/2019 16:11, Tom Lane wrote:
> > > ... so, have we beaten this topic to death yet? Can we make a decision?
> > >
> > > Personally, I'd be happy with either of the last two patch versio
On 2019-Feb-14, Peter Eisentraut wrote:
> On 14/02/2019 16:11, Tom Lane wrote:
> > ... so, have we beaten this topic to death yet? Can we make a decision?
> >
> > Personally, I'd be happy with either of the last two patch versions
> > I posted (that is, either AS [[NOT] MATERIALIZED] or
> > AS [
On 06/02/2019 10:00, Bruce Momjian wrote:
> I think "materialize" is the right word since "materialized" would be
> past tense.
It's an adjective. The sentence is, "with foo as the materialized
$query, do the $main_query".
It's the same as "materialized view".
--
Peter Eisentraut
On 14/02/2019 16:11, Tom Lane wrote:
> ... so, have we beaten this topic to death yet? Can we make a decision?
>
> Personally, I'd be happy with either of the last two patch versions
> I posted (that is, either AS [[NOT] MATERIALIZED] or
> AS [MATERIALIZE [ON|OFF]] syntax). But we gotta pick som
... so, have we beaten this topic to death yet? Can we make a decision?
Personally, I'd be happy with either of the last two patch versions
I posted (that is, either AS [[NOT] MATERIALIZED] or
AS [MATERIALIZE [ON|OFF]] syntax). But we gotta pick something.
regards, tom l
Andrew Gierth writes:
> "Tom" == Tom Lane writes:
> Tom> After further reflection I really don't like Andrew's suggestion
> Tom> that we not document the rule that multiply-referenced CTEs won't
> Tom> be inlined by default. That would be giving up the principle that
> Tom> WITH calculations
On Sat, Feb 2, 2019 at 02:01:01PM -0500, Tom Lane wrote:
> I wrote:
> > I propose that we implement and document this as
> > WITH ctename AS [ MATERIALIZE { ON | OFF } ] ( query )
> > which is maybe a bit clunky but not awful, and it would leave room
> > to generalize it to "AS [ optionname op
Vik Fearing writes:
> On 28/01/2019 23:05, Tom Lane wrote:
>> Peter Eisentraut writes:
>>> Or put it at the end?
>>> WITH ctename AS ( query ) MATERIALIZED
>> Yeah, I thought about that too, but it doesn't seem like an improvement.
>> If the query is very long (which isn't unlikely) I think peop
On 28/01/2019 23:05, Tom Lane wrote:
> Peter Eisentraut writes:
>> On 28/01/2019 21:35, Tom Lane wrote:
>>> Conceivably we could make it work without the parens:
>>> ...
>
>> Or put it at the end?
>> WITH ctename AS ( query ) MATERIALIZED
>
> Yeah, I thought about that too, but it doesn't se
> "Tom" == Tom Lane writes:
Tom> After further reflection I really don't like Andrew's suggestion
Tom> that we not document the rule that multiply-referenced CTEs won't
Tom> be inlined by default. That would be giving up the principle that
Tom> WITH calculations are not done multiple time
På lørdag 02. februar 2019 kl. 20:01:01, skrev Tom Lane mailto:t...@sss.pgh.pa.us>>: [snip]
There's nothing particularly stopping us from accepting
"materialized" with a D in this syntax, instead of or in addition
to "materialize"; though I hesitate to mention it for fear of
another round of bi
I wrote:
> I propose that we implement and document this as
> WITH ctename AS [ MATERIALIZE { ON | OFF } ] ( query )
> which is maybe a bit clunky but not awful, and it would leave room
> to generalize it to "AS [ optionname optionvalue [ , ... ] ]" if we
> ever need to. Looking at the prece
On Tuesday, January 29, 2019, Tom Lane wrote:
> Merlin Moncure writes:
> > On Tue, Jan 29, 2019 at 1:53 PM Tom Lane wrote:
> >> I propose that we implement and document this as
> >> WITH ctename AS [ MATERIALIZE { ON | OFF } ] ( query )
>
> > I hate to bikeshed here, but I think it's better eng
David Fetter writes:
> On Tue, Jan 29, 2019 at 02:52:44PM -0500, Tom Lane wrote:
>> I propose that we implement and document this as
>> WITH ctename AS [ MATERIALIZE { ON | OFF } ] ( query )
> I think this would be better with parentheses like this:
> WITH ctename [ ( MATERIALIZE { ON | OFF
On Tue, Jan 29, 2019 at 02:52:44PM -0500, Tom Lane wrote:
> Michael Paquier writes:
> > On Mon, Jan 28, 2019 at 05:05:32PM -0500, Tom Lane wrote:
> >> Yeah, I thought about that too, but it doesn't seem like an improvement.
> >> If the query is very long (which isn't unlikely) I think people would
On 1/29/19 3:36 PM, Merlin Moncure wrote:
> I hate to bikeshed here, but I think it's better english using that
> style of syntax to say,
> WITH ctename AS [ MATERIALIZATION { ON | OFF } ] ( query )
I had been just about to also engage in bikeshedding, on grounds
that (to me) the MATERIALIZED/NOT
Merlin Moncure writes:
> On Tue, Jan 29, 2019 at 1:53 PM Tom Lane wrote:
>> I propose that we implement and document this as
>> WITH ctename AS [ MATERIALIZE { ON | OFF } ] ( query )
> I hate to bikeshed here, but I think it's better english using that
> style of syntax to say,
> WITH ctename A
On Tue, Jan 29, 2019 at 1:53 PM Tom Lane wrote:
>
> Michael Paquier writes:
> > On Mon, Jan 28, 2019 at 05:05:32PM -0500, Tom Lane wrote:
> >> Yeah, I thought about that too, but it doesn't seem like an improvement.
> >> If the query is very long (which isn't unlikely) I think people would
> >> p
Michael Paquier writes:
> On Mon, Jan 28, 2019 at 05:05:32PM -0500, Tom Lane wrote:
>> Yeah, I thought about that too, but it doesn't seem like an improvement.
>> If the query is very long (which isn't unlikely) I think people would
>> prefer to see the option(s) up front.
> Having these options
On Mon, Jan 28, 2019 at 05:05:32PM -0500, Tom Lane wrote:
> Yeah, I thought about that too, but it doesn't seem like an improvement.
> If the query is very long (which isn't unlikely) I think people would
> prefer to see the option(s) up front.
Having these options at the front of the WITH clause
On 1/28/19 10:54 PM, Peter Eisentraut wrote:
Or put it at the end?
WITH ctename AS ( query ) MATERIALIZED
Hm, seems like that would be easy to miss for long queries.
Andreas
Peter Eisentraut writes:
> On 28/01/2019 21:35, Tom Lane wrote:
>> Conceivably we could make it work without the parens:
>> ...
> Or put it at the end?
> WITH ctename AS ( query ) MATERIALIZED
Yeah, I thought about that too, but it doesn't seem like an improvement.
If the query is very long
On 28/01/2019 21:35, Tom Lane wrote:
> Conceivably we could make it work without the parens:
>
> WITH ctename AS [ option = value [ , ] ] ( query )
>
> which for the immediate feature I'd be tempted to spell as
>
> WITH ctename AS [ materialize = on/off ] ( query ... )
>
> I t
Robert Haas writes:
> However, generally we have not had great luck with just sticking
> keywords in there (cf. VACUUM, ANALYZE, EXPLAIN, COPY) which is why I
> suggested using a flexible syntax with parenthesized options.
Fair, except that as you then proceed to point out, that does not work
eit
On Sun, Jan 27, 2019 at 8:23 AM Andrew Gierth
wrote:
> I think it makes more sense to say
> that we never inline if MATERIALIZED is specified, that we always inline
> if NOT MATERIALIZED is specified, and that if neither is specified the
> planner will choose (but perhaps note that currently it al
On Mon, Jan 21, 2019 at 10:28 AM Tom Lane wrote:
> Andreas Karlsson writes:
> > I have a minor biksheddish question about the syntax.
> > You proposed:
> > WITH cte_name [[NOT] MATERIALIZED] AS (query) main_query
> > While Andrew proposed:
> > WITH cte_name AS [[NOT] MATERIALIZED] (query) main_qu
On 1/26/19 11:55 PM, Tom Lane wrote:> Hearing no immediate pushback on
that proposal, I went ahead and made
a version of the patch that does it like that, as attached. I also took
a stab at documenting it fully.
Thanks! This version of the patch looks solid, including the
documentation. The o
On 1/27/19 4:21 PM, Tom Lane wrote:
Andrew Gierth writes:
I'm not sure we should nail down the rule that the absence of NOT
MATERIALIZED will mean a multiply-referenced CTE is evaluated once. One
would hope that in the future the planner might be taught to inline or
not in that case depending o
Andrew Gierth writes:
> I'm not sure we should nail down the rule that the absence of NOT
> MATERIALIZED will mean a multiply-referenced CTE is evaluated once. One
> would hope that in the future the planner might be taught to inline or
> not in that case depending on cost. I think it makes more s
> "Tom" == Tom Lane writes:
Tom> I was interested to find, while writing the docs, that it's a real
Tom> struggle to invent plausible reasons to write MATERIALIZED given
Tom> the above specification. You pretty much have to have lied to the
Tom> planner, eg by making a volatile function t
On Sat, Jan 26, 2019 at 12:22 AM Tom Lane wrote:
> Therefore, I'm reversing my previous opinion that we should not have
> an explicit NOT MATERIALIZED option. I think we should add that, and
> the behavior ought to be:
>
> * No option given: inline if there's exactly one reference.
>
> * With MA
I wrote:
> Therefore, I'm reversing my previous opinion that we should not have
> an explicit NOT MATERIALIZED option. I think we should add that, and
> the behavior ought to be:
> * No option given: inline if there's exactly one reference.
> * With MATERIALIZED: never inline.
> * With NOT MATERIA
Andreas Karlsson writes:
> [ inlining-ctes-v8.patch ]
I went ahead and pushed the stuff about QTW_EXAMINE_RTES_BEFORE/_AFTER,
because that seems like an independent change with other possible uses.
Attached is an updated version of the rest of the patch, with mostly
cosmetic changes. I've not t
On 22/01/2019 02:40, Andreas Karlsson wrote:
On 1/18/19 9:34 PM, Robert Haas wrote:
On Thu, Jan 17, 2019 at 10:48 AM Andreas Karlsson
wrote:
On 1/11/19 8:10 PM, Robert Haas wrote:
WITH cte_name [[NOT] MATERIALIZED] AS (query) main_query...
Hm, when would one want "NOT MATERIALIZED"? I am no
On 1/10/19 2:28 AM, Andreas Karlsson wrote:
Here is a new version of the patch with added tests, improved comments,
some minor code cleanup and most importantly slightly changed logic for
when we should inline.
Add ctematerialized to the JumbleExpr() in pg_stat_statements on
suggestion from A
Andreas Karlsson writes:
> I have a minor biksheddish question about the syntax.
> You proposed:
> WITH cte_name [[NOT] MATERIALIZED] AS (query) main_query
> While Andrew proposed:
> WITH cte_name AS [[NOT] MATERIALIZED] (query) main_query
> Do people have any preference between these two?
FWIW,
On 1/18/19 9:34 PM, Robert Haas wrote:
On Thu, Jan 17, 2019 at 10:48 AM Andreas Karlsson wrote:
On 1/11/19 8:10 PM, Robert Haas wrote:
WITH cte_name [[NOT] MATERIALIZED] AS (query) main_query...
Hm, when would one want "NOT MATERIALIZED"? I am not sure I see the
usefulness of forcing inlinin
On Fri, Jan 18, 2019 at 3:42 PM Andres Freund wrote:
> On 2019-01-18 15:34:46 -0500, Robert Haas wrote:
> > On Thu, Jan 17, 2019 at 10:48 AM Andreas Karlsson wrote:
> > > On 1/11/19 8:10 PM, Robert Haas wrote:
> > > > WITH cte_name [[NOT] MATERIALIZED] AS (query) main_query...
> > >
> > > Hm, whe
On 2019-01-18 15:34:46 -0500, Robert Haas wrote:
> On Thu, Jan 17, 2019 at 10:48 AM Andreas Karlsson wrote:
> > On 1/11/19 8:10 PM, Robert Haas wrote:
> > > WITH cte_name [[NOT] MATERIALIZED] AS (query) main_query...
> >
> > Hm, when would one want "NOT MATERIALIZED"? I am not sure I see the
> > u
On Thu, Jan 17, 2019 at 10:48 AM Andreas Karlsson wrote:
> On 1/11/19 8:10 PM, Robert Haas wrote:
> > WITH cte_name [[NOT] MATERIALIZED] AS (query) main_query...
>
> Hm, when would one want "NOT MATERIALIZED"? I am not sure I see the
> usefulness of forcing inlining other than if we by default do
Andreas Karlsson writes:
> On 1/11/19 8:10 PM, Robert Haas wrote:
>> WITH cte_name [[NOT] MATERIALIZED] AS (query) main_query...
> Hm, when would one want "NOT MATERIALIZED"? I am not sure I see the
> usefulness of forcing inlining other than if we by default do not inline
> when a CTE is refer
On 1/11/19 8:10 PM, Robert Haas wrote:
WITH cte_name [[NOT] MATERIALIZED] AS (query) main_query...
Hm, when would one want "NOT MATERIALIZED"? I am not sure I see the
usefulness of forcing inlining other than if we by default do not inline
when a CTE is referenced multiple times.
Do you ima
pá 11. 1. 2019 v 20:11 odesílatel Robert Haas
napsal:
> On Fri, Jan 11, 2019 at 2:04 PM Andres Freund wrote:
> > > Maybe we could consider a more extensible syntax that is attached to
> > > the contained SELECT rather than the containing WITH. Then CTEs would
> > > be less special; there'd be a
On Tue, Jul 24, 2018 at 6:10 PM Andres Freund wrote:
> My read of the concensus (in which I am in the majority, so I might be
> biased) is that we do want inlining to be the default. We were thinking
> that it'd be necessary to provide a way to force inlining on the SQL
> level for individual CTEs
On Fri, Jan 11, 2019 at 2:10 PM Robert Haas wrote:
>
> On Fri, Jan 11, 2019 at 2:04 PM Andres Freund wrote:
> > > Maybe we could consider a more extensible syntax that is attached to
> > > the contained SELECT rather than the containing WITH. Then CTEs would
> > > be less special; there'd be a p
On Fri, Jan 11, 2019 at 2:04 PM Andres Freund wrote:
> > Maybe we could consider a more extensible syntax that is attached to
> > the contained SELECT rather than the containing WITH. Then CTEs would
> > be less special; there'd be a place to put hints controlling top-level
> > queries, subselect
Hi,
On 2019-01-12 07:58:39 +1300, Thomas Munro wrote:
> On Sat, Jan 12, 2019 at 7:19 AM Andres Freund wrote:
> > On 2019-01-11 11:12:25 -0500, Robert Haas wrote:
> > > I actually think that we should go "all in" here and allow the user to
> > > specify either that they want materialization or tha
On Sat, Jan 12, 2019 at 7:19 AM Andres Freund wrote:
> On 2019-01-11 11:12:25 -0500, Robert Haas wrote:
> > I actually think that we should go "all in" here and allow the user to
> > specify either that they want materialization or that they don't want
> > materialization. If they specify neither
On Fri, Jan 11, 2019 at 1:49 PM David Fetter wrote:
> I don't see those as the same thing even slightly. Functions are
> Turing complete, generally speaking, which means that unless we send
> along those descriptors, we're asking the planner to solve the Halting
> Problem.
So... your argument is
On Fri, Jan 11, 2019 at 11:12:25AM -0500, Robert Haas wrote:
> > I know this is a thorny topic, but I have to say that I am uneasy
> > about the MATERIALIZED syntax. Here's how you write that in some
> > other RDBMS that loves hints:
> >
> > WITH foo AS (SELECT /*+ MATERIALIZE */ ...)
> >
> > I un
On 2019-01-11 11:12:25 -0500, Robert Haas wrote:
> I actually think that we should go "all in" here and allow the user to
> specify either that they want materialization or that they don't want
> materialization. If they specify neither, then we make some decision
> which we may change in a future
> I know this is a thorny topic, but I have to say that I am uneasy
> about the MATERIALIZED syntax. Here's how you write that in some
> other RDBMS that loves hints:
>
> WITH foo AS (SELECT /*+ MATERIALIZE */ ...)
>
> I understood that it was a long standing project policy that we don't
> want pl
On Thu, Jan 10, 2019 at 2:28 PM Andreas Karlsson wrote:
> 2. Feedback on the new syntax. I am personally fine with the current
> syntax, but it was just something I just quickly hacked together to move
> the patch forward and which also solved my personal uses cases.
Thanks for working on this.
Here is a new version of the patch with added tests, improved comments,
some minor code cleanup and most importantly slightly changed logic for
when we should inline.
The current strategy is to always inline unless the CTE is recursive or
it has side effects, i.e. it is a DML query, it contain
On 1/1/19 1:42 AM, Andrew Gierth wrote:
"Andreas" == Andreas Karlsson writes:
Andreas> I believe I have fixed these except for the comment on the
Andreas> conditions for when we inline.
Andreas> Andrew Gierth: Why did you chose to not inline on FOR UPDATE
Andreas> but inline volatile
On 1/1/19 3:18 AM, Andrew Gierth wrote:
I had a comment around here which seems to have been lost:
* Secondly, views (and explicit subqueries) currently have
* different behaviour w.r.t. SELECT FOR UPDATE than CTEs do. A
* FOR UPDATE clause is treated as extending into views and
* subque
> "Andreas" == Andreas Karlsson writes:
Andreas> + if (rte->rtekind == RTE_CTE &&
Andreas> + strcmp(rte->ctename, context->ctename) == 0 &&
Andreas> + rte->ctelevelsup == context->levelsup)
Andreas> + {
Andreas> + Query *newquery = copyObject(context->ctequery);
An
> "Andreas" == Andreas Karlsson writes:
Andreas> I believe I have fixed these except for the comment on the
Andreas> conditions for when we inline.
Andreas> Andrew Gierth: Why did you chose to not inline on FOR UPDATE
Andreas> but inline volatile functions? I feel that this might be
And
On 11/16/18 10:15 PM, Tom Lane wrote:
> I took a little bit of a look through this. Some thoughts:
Thanks for the review! I have decided to pick up this patch and work on
it since nothing has happened in a while. Here is a new version with
most of the feedback fixed.
* This is not the idiom
On Sat, 17 Nov 2018 at 10:12, Stephen Frost wrote:
> Greetings,
>
> * Andrew Gierth (and...@tao11.riddles.org.uk) wrote:
> > > "Tom" == Tom Lane writes:
> >
> > >> [ inlining-ctes-v5.patch ]
> >
> > Tom> I took a little bit of a look through this. Some thoughts:
> >
> > Tom> * I think it
Greetings,
* Andrew Gierth (and...@tao11.riddles.org.uk) wrote:
> > "Tom" == Tom Lane writes:
>
> >> [ inlining-ctes-v5.patch ]
>
> Tom> I took a little bit of a look through this. Some thoughts:
>
> Tom> * I think it'd be a good idea if we made OFFSET/LIMIT in a CTE be
> Tom> an alte
Andrew Gierth writes:
> "Tom" == Tom Lane writes:
> Tom> * I have no faith in the idea that we can skip doing a copyObject
> Tom> on the inlined subquery, except maybe in the case where we know
> Tom> there's exactly one reference.
> The code doesn't do a copyObject on the query if there are
> "Tom" == Tom Lane writes:
>> [ inlining-ctes-v5.patch ]
Tom> I took a little bit of a look through this. Some thoughts:
Tom> * I think it'd be a good idea if we made OFFSET/LIMIT in a CTE be
Tom> an alternate way of keeping it from being inlined. As the patch
Tom> stands, if that's
On Fri, Nov 16, 2018 at 04:15:10PM -0500, Tom Lane wrote:
> Andreas Karlsson writes:
> > [ inlining-ctes-v5.patch ]
>
> I took a little bit of a look through this. Some thoughts:
>
> * I think it'd be a good idea if we made OFFSET/LIMIT in a CTE be an
> alternate way of keeping it from being i
Andreas Karlsson writes:
> [ inlining-ctes-v5.patch ]
I took a little bit of a look through this. Some thoughts:
* I think it'd be a good idea if we made OFFSET/LIMIT in a CTE be an
alternate way of keeping it from being inlined. As the patch stands,
if that's the behavior you want, you have
> "David" == David Fetter writes:
>> Consider the difference between (in the absence of CTE inlining):
>>
>> -- inline subquery with no optimization barrier (qual may be pushed down)
>> select * from (select x from y) s where x=1;
David> ...and doesn't need to materialize all of y,
>
On Fri, Oct 05, 2018 at 01:40:05AM +0100, Andrew Gierth wrote:
> > "Andreas" == Andreas Karlsson writes:
>
> > On 10/03/2018 05:57 PM, David Fetter wrote:
> >> Is there any meaningful distinction between "inlining," by which I
> >> mean converting to a subquery, and predicate pushdown, whi
> "Andreas" == Andreas Karlsson writes:
> On 10/03/2018 05:57 PM, David Fetter wrote:
>> Is there any meaningful distinction between "inlining," by which I
>> mean converting to a subquery, and predicate pushdown, which
>> would happen at least for a first cut, at the rewrite stage?
Yes.
On Thu, Oct 04, 2018 at 11:22:32AM +0200, Andreas Karlsson wrote:
> On 10/03/2018 05:57 PM, David Fetter wrote:
> >Is there any meaningful distinction between "inlining," by which I
> >mean converting to a subquery, and predicate pushdown, which
> >would happen at least for a first cut, at the rewr
On 10/03/2018 05:57 PM, David Fetter wrote:
Is there any meaningful distinction between "inlining," by which I
mean converting to a subquery, and predicate pushdown, which
would happen at least for a first cut, at the rewrite stage?
Sorry, but I do not think I understand your question. The abil
On Tue, Oct 02, 2018 at 12:03:06PM +0200, Andreas Karlsson wrote:
> Hi,
>
> Here is an updated patch which adds some simple syntax for adding the
> optimization barrier. For example:
>
> WITH x AS MATERIALIZED (
>SELECT 1
> )
> SELECT * FROM x;
>
> Andreas
This is great!
Is there any meani
Hi,
Here is an updated patch which adds some simple syntax for adding the
optimization barrier. For example:
WITH x AS MATERIALIZED (
SELECT 1
)
SELECT * FROM x;
Andreas
diff --git a/contrib/postgres_fdw/expected/postgres_fdw.out b/contrib/postgres_fdw/expected/postgres_fdw.out
index 21a2e
On 07/27/2018 10:10 AM, David Fetter wrote:
On Fri, Jul 27, 2018 at 02:55:26PM +1200, Thomas Munro wrote:
On Thu, Jul 26, 2018 at 7:14 AM, David Fetter wrote:
Please find attached the next version, which passes 'make check'.
... but not 'make check-world' (contrib/postgres_fdw's EXPLAIN is d
Hi,
On 2018-08-08 16:55:22 +1200, Thomas Munro wrote:
> On Fri, Jul 27, 2018 at 8:10 PM, David Fetter wrote:
> > On Fri, Jul 27, 2018 at 02:55:26PM +1200, Thomas Munro wrote:
> >> On Thu, Jul 26, 2018 at 7:14 AM, David Fetter wrote:
> >> > Please find attached the next version, which passes 'mak
On Fri, Jul 27, 2018 at 8:10 PM, David Fetter wrote:
> On Fri, Jul 27, 2018 at 02:55:26PM +1200, Thomas Munro wrote:
>> On Thu, Jul 26, 2018 at 7:14 AM, David Fetter wrote:
>> > Please find attached the next version, which passes 'make check'.
>>
>> ... but not 'make check-world' (contrib/postgre
> "Andreas" == Andreas Karlsson writes:
>> WITH ctename AS [[NOT] MATERIALIZED] (query)
Andreas> I think "NOT MATERIALIZED" would be a bit misleading since the
Andreas> planner may choose to materialize anyway,
It would certainly be possible to make an explicit NOT MATERIALIZED
override
On Fri, Jul 27, 2018 at 02:55:26PM +1200, Thomas Munro wrote:
> On Thu, Jul 26, 2018 at 7:14 AM, David Fetter wrote:
> > Please find attached the next version, which passes 'make check'.
>
> ... but not 'make check-world' (contrib/postgres_fdw's EXPLAIN is different).
Please find attached a patc
On Thu, Jul 26, 2018 at 7:14 AM, David Fetter wrote:
> Please find attached the next version, which passes 'make check'.
... but not 'make check-world' (contrib/postgres_fdw's EXPLAIN is different).
--
Thomas Munro
http://www.enterprisedb.com
On Thu, Jul 26, 2018 at 02:51:53PM +0200, Andreas Karlsson wrote:
> On 07/25/2018 06:08 PM, Andrew Gierth wrote:
> >WITH ctename AS [[NOT] MATERIALIZED] (query)
>
> I think "NOT MATERIALIZED" would be a bit misleading since the
> planner may choose to materialize anyway, so I suggest skipping that
On 07/25/2018 06:08 PM, Andrew Gierth wrote:
WITH ctename AS [[NOT] MATERIALIZED] (query)
I think "NOT MATERIALIZED" would be a bit misleading since the planner
may choose to materialize anyway, so I suggest skipping that part of the
syntax unless there is a really strong reason for having it
On Wed, Jul 25, 2018 at 04:18:42PM +0100, Andrew Gierth wrote:
> > "David" == David Fetter writes:
>
> David> Please find attached a version rebased atop 167075be3ab1547e18
> David> with what I believe are appropriate changes to regression test
> David> output. The other changes to the reg
On Tue, Jul 24, 2018 at 07:57:49PM -0400, Tom Lane wrote:
> Andres Freund writes:
> > On 2018-07-24 19:49:19 -0400, Tom Lane wrote:
> >> However, a singly-referenced SELECT CTE could reasonably be treated as
> >> equivalent to a sub-select-in-FROM, and then you would have the same
> >> mechanisms
On Wed, Jul 25, 2018 at 05:08:43PM +0100, Andrew Gierth wrote:
> Nico> It is possible to add a keyword for this purpose in the WITH syntax:
>
> Nico> WITH VIEW (...) AS a_view
>
> The existing (and standard) syntax is WITH ctename AS (query).
Oy, I flubbed that up.
> Syntaxes that have
> "Nico" == Nico Williams writes:
Nico> It is possible to add a keyword for this purpose in the WITH syntax:
Nico> WITH VIEW (...) AS a_view
The existing (and standard) syntax is WITH ctename AS (query).
Syntaxes that have been suggested for explicitly controlling the
materializati
On Wed, Jul 25, 2018 at 07:42:37AM +0200, David Fetter wrote:
> Please find attached a version rebased atop 167075be3ab1547e18 with
> what I believe are appropriate changes to regression test output. The
> other changes to the regression tests output are somewhat puzzling, as
> they change the act
> "David" == David Fetter writes:
David> Please find attached a version rebased atop 167075be3ab1547e18
David> with what I believe are appropriate changes to regression test
David> output. The other changes to the regression tests output are
David> somewhat puzzling, as they change the ac
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