Re: [HACKERS] Socket problem using beta2 on Windows-XP

2005-09-30 Thread Magnus Hagander
IIRC, the win32 installer will enable autovacuum by default. And yes, autovacuum was my first thought as well after Thomas last mail - that would be a good explanation to why it happens when the postmaster is idle. I used the win32 installer defaults so autovacuum is probably

Re: [HACKERS] Socket problem using beta2 on Windows-XP

2005-09-30 Thread Thomas Hallgren
Magnus Hagander wrote: Right. Please try turning it off and see if the problem goes away. It does (go away). - thomas ---(end of broadcast)--- TIP 4: Have you searched our list archives? http://archives.postgresql.org

Re: [HACKERS] Socket problem using beta2 on Windows-XP

2005-09-30 Thread Thomas Hallgren
Magnus Hagander wrote: Right. Please try turning it off and see if the problem goes away. No, wait! It does *not* go away. Do I need to do anything more than setting this in my postgresql.conf file: autovacuum = false# enable autovacuum subprocess? and restart the service?

Re: [HACKERS] Socket problem using beta2 on Windows-XP

2005-09-30 Thread Magnus Hagander
Right. Please try turning it off and see if the problem goes away. No, wait! It does *not* go away. Do I need to do anything more than setting this in my postgresql.conf file: autovacuum = false# enable autovacuum subprocess? and restart the service? The two zombie

[HACKERS] FW: PGBuildfarm member snake Branch HEAD Status changed from OK to Contrib failure

2005-09-30 Thread Dave Page
Looks like there more unprotable code in the recent changes to pgbench :-( Regards, Dave. -Original Message- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] Sent: 30 September 2005 02:17 To: [EMAIL PROTECTED]; [EMAIL PROTECTED] Subject: PGBuildfarm member snake Branch HEAD

Re: [HACKERS] Socket problem using beta2 on Windows-XP

2005-09-30 Thread Alvaro Herrera
On Fri, Sep 30, 2005 at 08:29:07AM +0200, Thomas Hallgren wrote: Magnus Hagander wrote: Right. Please try turning it off and see if the problem goes away. No, wait! It does *not* go away. Do I need to do anything more than setting this in my postgresql.conf file: autovacuum = false

Re: [HACKERS] Install pg_regress script to support PGXS?

2005-09-30 Thread Fabien COELHO
Dear Tom, While testing the recent pgxs patch, I noticed that you can build and install contrib with PGXS: ... It seems that it ought to work to run installcheck too: gmake USE_PGXS=1 installcheck but this does not quite work because the pg_regress script isn't included in the

Re: [HACKERS] [PERFORM] A Better External Sort?

2005-09-30 Thread Ron Peacetree
From: Pailloncy Jean-Gerard [EMAIL PROTECTED] Sent: Sep 29, 2005 7:11 AM Subject: Re: [HACKERS] [PERFORM] A Better External Sort? Jeff Baker: Your main example seems to focus on a large table where a key column has constrained values. This case is interesting in proportion to the number of

Re: [HACKERS] [PERFORM] A Better External Sort?

2005-09-30 Thread Ron Peacetree
From: Zeugswetter Andreas DAZ SD [EMAIL PROTECTED] Sent: Sep 29, 2005 9:28 AM Subject: RE: [HACKERS] [PERFORM] A Better External Sort? In my original example, a sequential scan of the 1TB of 2KB or 4KB records, = 250M or 500M records of data, being sorted on a binary value key will take ~1000x

Re: [HACKERS] [PERFORM] A Better External Sort?

2005-09-30 Thread Ron Peacetree
From: Josh Berkus josh@agliodbs.com Sent: Sep 29, 2005 12:54 PM Subject: Re: [HACKERS] [PERFORM] A Better External Sort? The biggest single area where I see PostgreSQL external sort sucking is on index creation on large tables. For example, for free version of TPCH, it takes only 1.5 hours to

Re: [HACKERS] postgresql clustering

2005-09-30 Thread Daniel Duvall
Thanks for your reply Luke. Bizgres looks like a very promissing project. I'll be sure to follow it. Thanks to everyone for their comments. I'm starting to understand the truth behind the hype and where these performance gains and hits stem from. -Dan ---(end of

Re: [HACKERS] postgresql clustering

2005-09-30 Thread Daniel Duvall
What about clustered filesystems? At first blush I would think the overhead of something like GFS might kill performance. Could one potentially achieve a fail-over config using multiple nodes with GFS, each having there own instance of PostgreSQL (but only one running at any given moment)?

Re: [HACKERS] [PERFORM] A Better External Sort?

2005-09-30 Thread PFC
Just to add a little anarchy in your nice debate... Who really needs all the results of a sort on your terabyte table ? I guess not many people do a SELECT from such a table and want all the results. So, this leaves : - Really wanting all the results, to fetch using

Fwd: Re: [HACKERS] postgresql clustering

2005-09-30 Thread Trent Shipley
What is the relationship between database support for clustering and grid computing and support for distributed databases? Two-phase COMMIT is comming in 8.1. What effect will this have in promoting FOSS grid support or distribution solutions for Postgresql? ---(end

Re: [HACKERS] Install pg_regress script to support PGXS?

2005-09-30 Thread Alvaro Herrera
On Thu, Sep 29, 2005 at 03:24:15PM +0200, Fabien COELHO wrote: Dear Tom, While testing the recent pgxs patch, I noticed that you can build and install contrib with PGXS: ... It seems that it ought to work to run installcheck too: gmake USE_PGXS=1 installcheck but this does not

Re: [HACKERS] Install pg_regress script to support PGXS?

2005-09-30 Thread Tom Lane
Alvaro Herrera [EMAIL PROTECTED] writes: (Maybe we should audit it for security problems, just in case the distributors choose to include it in packages. The temp file usage for $TMPFILE looks predictable, thus maybe it _is_ insecure. Apparently it can be made to clobber any existing file

Re: [HACKERS] Socket problem using beta2 on Windows-XP

2005-09-30 Thread Tom Lane
Alvaro Herrera [EMAIL PROTECTED] writes: If it's two zombies per minute, then I bet it's the stat collector and stat bufferer. They are restarted by the postmaster if not found to be running. That would make some sense, because the stat processes need to set up new sockets (for the pipe

Re: [HACKERS] Socket problem using beta2 on Windows-XP

2005-09-30 Thread Magnus Hagander
If it's two zombies per minute, then I bet it's the stat collector and stat bufferer. They are restarted by the postmaster if not found to be running. That would make some sense, because the stat processes need to set up new sockets (for the pipe between them). The autovacuum

Re: [HACKERS] Found small issue with OUT params

2005-09-30 Thread Tony Caduto
Tom Lane wrote: Mike Rylander [EMAIL PROTECTED] writes: Using that logic, a functions with one OUT param would be the same as a function returning a rowtype with only one column, But it's not (and no, I don't want to make it so, because the overhead for the useless record result

Re: [HACKERS] Found small issue with OUT params

2005-09-30 Thread Martijn van Oosterhout
On Fri, Sep 30, 2005 at 10:20:34AM -0500, Tony Caduto wrote: Tom, I hardly think the overhead would be significant on modern processors, I don't think the majority of users are running on Pentium 90s.( I am assuming you mean a performance overhead) Um, please read the documention. Returning

Re: [HACKERS] Socket problem using beta2 on Windows-XP

2005-09-30 Thread Thomas Hallgren
Tom Lane wrote: However, why two zombies? That would mean that the grandchild process started, which should mean that the pipe was already created ... To clarify, I talk about the tcpview window and connections, and thus zombi-connections. They both belong to the same pid and seems to

Re: [HACKERS] [PERFORM] A Better External Sort?

2005-09-30 Thread Josh Berkus
Ron, Hmmm. 60GB/5400secs= 11MBps. That's ssllooww. So the first problem is evidently our physical layout and/or HD IO layer sucks. Actually, it's much worse than that, because the sort is only dealing with one column. As I said, monitoring the iostat our top speed was 2.2mb/s. --Josh

Re: [HACKERS] Found small issue with OUT params

2005-09-30 Thread Tony Caduto
Martijn van Oosterhout wrote: On Fri, Sep 30, 2005 at 10:20:34AM -0500, Tony Caduto wrote: Tom, I hardly think the overhead would be significant on modern processors, I don't think the majority of users are running on Pentium 90s.( I am assuming you mean a performance overhead) Um,

Re: [HACKERS] [PERFORM] A Better External Sort?

2005-09-30 Thread Dann Corbit
-Original Message- From: [EMAIL PROTECTED] [mailto:pgsql-hackers- [EMAIL PROTECTED] On Behalf Of PFC Sent: Thursday, September 29, 2005 9:10 AM To: [EMAIL PROTECTED] Cc: Pg Hackers; pgsql-performance@postgresql.org Subject: Re: [HACKERS] [PERFORM] A Better External Sort?

Re: [HACKERS] Found small issue with OUT params

2005-09-30 Thread Joshua D. Drake
So you might notice little performance hit bringing back a million rows, and most of these type of single OUT params functions only return one row/value anyway. There would be zero perceivable difference in performance regardless of the extra overhead for a single value/row. Sounds like we

Re: [HACKERS] Found small issue with OUT params

2005-09-30 Thread Robert Treat
On Friday 30 September 2005 11:49, Martijn van Oosterhout wrote: On Fri, Sep 30, 2005 at 10:20:34AM -0500, Tony Caduto wrote: Tom, I hardly think the overhead would be significant on modern processors, I don't think the majority of users are running on Pentium 90s.( I am assuming you mean

Re: [HACKERS] [PERFORM] A Better External Sort?

2005-09-30 Thread Josh Berkus
Ron, That 11MBps was your =bulk load= speed. If just loading a table is this slow, then there are issues with basic physical IO, not just IO during sort operations. Oh, yeah. Well, that's separate from sort. See multiple posts on this list from the GreenPlum team, the COPY patch for 8.1,

Re: [HACKERS] [PERFORM] A Better External Sort?

2005-09-30 Thread Luke Lonergan
Ron, On 9/30/05 1:20 PM, Ron Peacetree [EMAIL PROTECTED] wrote: That 11MBps was your =bulk load= speed. If just loading a table is this slow, then there are issues with basic physical IO, not just IO during sort operations. Bulk loading speed is irrelevant here - that is dominated by

Re: [HACKERS] FW: PGBuildfarm member snake Branch HEAD Status changed from OK to Contrib failure

2005-09-30 Thread Alvaro Herrera
On Fri, Sep 30, 2005 at 10:08:11AM +0100, Dave Page wrote: Looks like there more unprotable code in the recent changes to pgbench :-( Here, the culprits are tfind() and tsearch(). These apparently aren't portable enough, but they seem to exist on all other platforms. Maybe we could come up

Re: [HACKERS] postgresql clustering

2005-09-30 Thread Luke Lonergan
Dan, On 9/29/05 3:23 PM, Daniel Duvall [EMAIL PROTECTED] wrote: What about clustered filesystems? At first blush I would think the overhead of something like GFS might kill performance. Could one potentially achieve a fail-over config using multiple nodes with GFS, each having there own

Re: [HACKERS] [PERFORM] A Better External Sort?

2005-09-30 Thread Dann Corbit
I see the following routines that seem to be related to sorting. If I were to examine these routines to consider ways to improve it, what routines should I key in on? I am guessing that tuplesort.c is the hub of activity for database sorting. Directory of

Re: [HACKERS] postgresql clustering

2005-09-30 Thread Hans-Jürgen Schönig
Luke Lonergan wrote: Dan, On 9/29/05 3:23 PM, Daniel Duvall [EMAIL PROTECTED] wrote: What about clustered filesystems? At first blush I would think the overhead of something like GFS might kill performance. Could one potentially achieve a fail-over config using multiple nodes with GFS,

Re: [HACKERS] \d on database with a lot of tables is slow

2005-09-30 Thread Jim C. Nasby
On Wed, Sep 28, 2005 at 11:35:31AM -0400, Tom Lane wrote: Jim C. Nasby [EMAIL PROTECTED] writes: Sorry, remembered it wrong. It's 'Did not find any relation named', which appears to be in bin/psql/describe.c. It does occur when trying to do a \d on a specific table. Hmm, no immediate

[HACKERS] Bug 1473, pthread python on FreeBSD

2005-09-30 Thread Jim C. Nasby
http://archives.postgresql.org/pgsql-bugs/2005-02/msg00135.php I think it may have been a bit early to disable pthread python support (http://archives.postgresql.org/pgsql-hackers/2005-09/msg01136.php), as Python was working fine on buildfarm member platypus. Maybe it's only an issue with 4.x

Re: [HACKERS] Vacuum questions...

2005-09-30 Thread Jim C. Nasby
On Thu, Sep 29, 2005 at 12:50:13AM +0300, Hannu Krosing wrote: On T, 2005-09-27 at 17:57 -0500, Jim C. Nasby wrote: On Tue, Sep 27, 2005 at 02:47:46PM -0400, Jan Wieck wrote: On 9/24/2005 8:17 PM, Jim C. Nasby wrote: Would it be difficult to vacuum as part of a dump? The reasoning

Re: [HACKERS] roundoff problem in time datatype

2005-09-30 Thread Jim C. Nasby
On Mon, Sep 26, 2005 at 06:23:06PM +0200, Andreas Pflug wrote: Tom Lane wrote: Dennis Bjorklund [EMAIL PROTECTED] writes: Do the sql standard say anything on the matter? It doesn't seem very helpful. AFAICS, we should interpret storing '23:59:59.99' into a TIME(0) field as a cast from

Re: [HACKERS] roundoff problem in time datatype

2005-09-30 Thread Jim C. Nasby
On Mon, Sep 26, 2005 at 11:46:47AM -0400, Tom Lane wrote: Jochem van Dieten [EMAIL PROTECTED] writes: On 9/26/05, Dennis Bjorklund wrote: One reason is because it's what the standard demand. Could you cite that? The only thing I can find in the SQL standard is that the hour field in an

Re: [HACKERS] FW: PGBuildfarm member snake Branch HEAD Status changed

2005-09-30 Thread Andrew Dunstan
Alvaro Herrera wrote: On Fri, Sep 30, 2005 at 10:08:11AM +0100, Dave Page wrote: Looks like there more unprotable code in the recent changes to pgbench :-( Here, the culprits are tfind() and tsearch(). These apparently aren't portable enough, but they seem to exist on all other

Re: [HACKERS] Open items list for 8.1

2005-09-30 Thread Jim C. Nasby
On Wed, Sep 28, 2005 at 06:07:02PM -0400, Neil Conway wrote: On Wed, 2005-28-09 at 18:35 -0300, Marc G. Fournier wrote: The problem isn't whether or not they should be changed, the problem is that they were changed *during* beta AND *against* the direction that discussion on these changes

Re: [HACKERS] On Logging

2005-09-30 Thread Jim C. Nasby
On Mon, Sep 26, 2005 at 10:57:54AM -0700, Ron Mayer wrote: David Fetter wrote: ...log file formats in 8.0 * CSV * YAML * XML * Piped logs, as Apache can do * DB handle. I know this one will be controversial. [...] 1. Am I the only one who would wants an option for machine-readable

Re: [HACKERS] Open items list for 8.1

2005-09-30 Thread Neil Conway
On Fri, 2005-30-09 at 17:47 -0500, Jim C. Nasby wrote: What's wrong with adding pg_cancel_backend(...) RETURNS int as an alias for the one that returns boolean, and document that it's deprecated and will be removed in the future. You can't overload functions based on their return type alone.

Re: [HACKERS] Open items list for 8.1

2005-09-30 Thread Bruce Momjian
Jim C. Nasby wrote: On Wed, Sep 28, 2005 at 06:07:02PM -0400, Neil Conway wrote: On Wed, 2005-28-09 at 18:35 -0300, Marc G. Fournier wrote: The problem isn't whether or not they should be changed, the problem is that they were changed *during* beta AND *against* the direction that

Re: [HACKERS] State of support for back PG branches

2005-09-30 Thread Jim C. Nasby
On Mon, Sep 26, 2005 at 09:07:45PM -0700, Joshua D. Drake wrote: A nice pg_upgrade utility would make a big difference. Clearly an in-place upgrade is possible, but maintaining is hard. There are two broad ways of running a pg_upgrade project - one that is entirely independent of the main

Re: [HACKERS] [PERFORM] A Better External Sort?

2005-09-30 Thread PFC
Bulk loading speed is irrelevant here - that is dominated by parsing, which we have covered copiously (har har) previously and have sped up by 500%, which still makes Postgres 1/2 the loading speed of MySQL. Let's ask MySQL 4.0 LOAD DATA INFILE blah 0 errors, 666 warnings SHOW

Re: [HACKERS] [PERFORM] A Better External Sort?

2005-09-30 Thread Ron Peacetree
That 11MBps was your =bulk load= speed. If just loading a table is this slow, then there are issues with basic physical IO, not just IO during sort operations. As I said, the obvious candidates are inefficient physical layout and/or flawed IO code. Until the basic IO issues are addressed, we

[HACKERS] Request for a force interactive mode flag (-I) for psql

2005-09-30 Thread Bill Bartlett
Back in 2003 Bruce Momjian proposed adding a flag (-I) to psql to force it into interactive mode. (See http://archives.postgresql.org/pgsql-hackers/2003-11/msg00013.php for the thread.) The proposal was rejected because there was no proven need for it at that time. I'd like to raise this

Re: [HACKERS] [PERFORM] A Better External Sort?

2005-09-30 Thread Jignesh K. Shah
I have seen similar performance as Josh and my reasoning is as follows: * WAL is the biggest bottleneck with its default size of 16MB. Many people hate to recompile the code to change its default, and increasing checkpoint segments help but still there is lot of overhead in the rotation of

Re: [HACKERS] State of support for back PG branches

2005-09-30 Thread Jim C. Nasby
On Mon, Sep 26, 2005 at 08:54:49PM -0700, Josh Berkus wrote: Tom, Or, as you say, we could take the viewpoint that there are commercial companies willing to take on the burden of supporting back releases, and the development community ought not spend its limited resources on doing that.

Re: [HACKERS] Database file compatability

2005-09-30 Thread Jim C. Nasby
On Wed, Sep 28, 2005 at 10:22:51AM -0400, Tom Lane wrote: Qingqing Zhou [EMAIL PROTECTED] writes: Tom Lane [EMAIL PROTECTED] wrote in message There is a possible sequence like this: ALIGNOF_LONG4 ALIGNOF_DOUBLE 8 MAXIMUM_ALIGNOF 8 vs. ALIGNOF_LONG8

Re: [HACKERS] PostgreSQL overall design

2005-09-30 Thread Jim C. Nasby
On Tue, Sep 27, 2005 at 07:00:14PM +0530, Gnanavel S wrote: On 9/27/05, Jonah H. Harris [EMAIL PROTECTED] wrote: Were you looking for a call graph? Yes. I want to know the list and sequence of files involved during a call. Total non-coder question, but is there an open-source utility

Re: [HACKERS] effective SELECT from child tables

2005-09-30 Thread Jim C. Nasby
On Wed, Sep 28, 2005 at 10:24:18PM +0200, Martijn van Oosterhout wrote: On Wed, Sep 28, 2005 at 11:00:46PM +0400, Ilia Kantor wrote: Your suggestion is essentially the same as mine.. There exists tableoid, pretty much suited to tell between tables in the case of inheritance.. I can't see a

Re: [HACKERS] effective SELECT from child tables

2005-09-30 Thread Jim C. Nasby
On Wed, Sep 28, 2005 at 07:25:46PM +0100, Simon Riggs wrote: Include the Discriminator as a column in A and it will be inherited by all A1, A2, A3. e.g. concrete_class char(1) not null snip This will add 1 byte per row in your superclass... and requires no I thought char was actually

Re: [HACKERS] [PERFORM] A Better External Sort?

2005-09-30 Thread Ron Peacetree
25MBps should not be a CPU bound limit for IO, nor should it be an OS limit. It should be something ~100x (Single channel RAM) to ~200x (dual channel RAM) that. For an IO rate of 25MBps to be pegging the CPU at 100%, the CPU is suffering some combination of A= lot's of cache misses (cache

Re: [HACKERS] Found small issue with OUT params

2005-09-30 Thread Jim C. Nasby
On Fri, Sep 30, 2005 at 10:53:22AM -0700, Joshua D. Drake wrote: So you might notice little performance hit bringing back a million rows, and most of these type of single OUT params functions only return one row/value anyway. There would be zero perceivable difference in performance

Re: [HACKERS] Query in SQL statement

2005-09-30 Thread Jim C. Nasby
On Thu, Sep 29, 2005 at 09:28:38PM +0800, Christopher Kings-Lynne wrote: CREATE SEQUENCE ai_id; CREATE TABLE badusers ( id int DEFAULT nextval('ai_id') NOT NULL, UserName varchar(30), Date datetime DEFAULT '-00-00 00:00:00' NOT NULL, Reason varchar(200), Admin varchar(30)

Re: [HACKERS] [PERFORM] A Better External Sort?

2005-09-30 Thread Dann Corbit
I have perused the tuple sort stuff. The good: The documentation of the sort algorithm from Knuth's TAOCP was beautifully done. Everyone who writes an algorithm should credit the original source like this, and also where it deviates. That was done very nicely. The bad: With random access, tape

Re: [HACKERS] PCTFree Results

2005-09-30 Thread Jim C. Nasby
On Thu, Sep 29, 2005 at 11:05:47AM -0400, Jonah H. Harris wrote: Has there been any movement on this? If not, I finally have some time to look at it. Well, here's the original thread: http://archives.postgresql.org/pgsql-hackers/2005-08/msg00637.php I think the problem is that the testing

Re: [HACKERS] Open items list for 8.1

2005-09-30 Thread Jim C. Nasby
On Fri, Sep 30, 2005 at 06:58:05PM -0400, Bruce Momjian wrote: We don't have the ability to have to functions that take the same parameters and return different results because there is no facility to decide which function to call based on what return value is expected, because a simple query

Re: [HACKERS] \d on database with a lot of tables is slow

2005-09-30 Thread Jon Jensen
On Fri, 30 Sep 2005, Jim C. Nasby wrote: ERROR: cache lookup failed for relation 1906465919 It is on an exact table name. When we retry the describe on a failure, sometimes it works and sometimes it fails again. When it fails again the relation number is different. Also, \d schema.table

Re: [HACKERS] Found small issue with OUT params

2005-09-30 Thread Bruce Momjian
Jim C. Nasby wrote: On Fri, Sep 30, 2005 at 10:53:22AM -0700, Joshua D. Drake wrote: So you might notice little performance hit bringing back a million rows, and most of these type of single OUT params functions only return one row/value anyway. There would be zero perceivable

Re: [HACKERS] Found small issue with OUT params

2005-09-30 Thread Mike Rylander
On 9/30/05, Jim C. Nasby [EMAIL PROTECTED] wrote: On Fri, Sep 30, 2005 at 10:53:22AM -0700, Joshua D. Drake wrote: So you might notice little performance hit bringing back a million rows, and most of these type of single OUT params functions only return one row/value anyway. There

Re: [HACKERS] On Logging

2005-09-30 Thread David Fetter
On Fri, Sep 30, 2005 at 05:54:49PM -0500, Jim C. Nasby wrote: On Mon, Sep 26, 2005 at 10:57:54AM -0700, Ron Mayer wrote: David Fetter wrote: ...log file formats in 8.0 * CSV * YAML * XML * Piped logs, as Apache can do * DB handle. I know this one will be controversial.

Re: [HACKERS] [PERFORM] A Better External Sort?

2005-09-30 Thread Gregory Maxwell
On 9/30/05, Ron Peacetree [EMAIL PROTECTED] wrote: 4= I'm sure we are paying all sorts of nasty overhead for essentially emulating the pg filesystem inside another filesystem. That means ~2x as much overhead to access a particular piece of data. The simplest solution is for us to implement a

Re: [HACKERS] [PERFORM] A Better External Sort?

2005-09-30 Thread Gregory Maxwell
On 9/28/05, Ron Peacetree [EMAIL PROTECTED] wrote: 2= We use my method to sort two different tables. We now have these very efficient representations of a specific ordering on these tables. A join operation can now be done using these Btrees rather than the original data tables that involves

[HACKERS] Expression index ignores column statistics target

2005-09-30 Thread Michael Fuhr
I've noticed that row count estimates for expression indexes appear to rely on default_statistics_target rather than on a column's actual statistics target. That is, if I use ALTER TABLE SET STATISTICS to increase a column's statistics target and then run ANALYZE, then estimates for

Re: [HACKERS] Expression index ignores column statistics target

2005-09-30 Thread Bruce Momjian
This is expected. The main TODO items is: * Allow accurate statistics to be collected on indexes with more than one column or expression indexes, perhaps using per-index statistics Basically, we don't have multi-column or expression statistics. ANALYZE just analyzes

Re: [HACKERS] Expression index ignores column statistics target

2005-09-30 Thread Tom Lane
Michael Fuhr [EMAIL PROTECTED] writes: I've noticed that row count estimates for expression indexes appear to rely on default_statistics_target rather than on a column's actual statistics target. That is, if I use ALTER TABLE SET STATISTICS to increase a column's statistics target and then

Re: [HACKERS] Expression index ignores column statistics target

2005-09-30 Thread Michael Fuhr
On Fri, Sep 30, 2005 at 11:59:26PM -0400, Bruce Momjian wrote: This is expected. The main TODO items is: * Allow accurate statistics to be collected on indexes with more than one column or expression indexes, perhaps using per-index statistics Basically, we don't have

Re: [HACKERS] Expression index ignores column statistics target

2005-09-30 Thread Michael Fuhr
On Sat, Oct 01, 2005 at 12:53:03AM -0400, Tom Lane wrote: The code does in fact honor per-column statistics targets attached to expression indexes, viz alter table myfuncindex alter column pg_expression_1 set statistics 100; Aha -- that's the piece I didn't know about. I was wondering where

Re: [HACKERS] [PERFORM] A Better External Sort?

2005-09-30 Thread Dann Corbit
Judy definitely rates a WOW!! -Original Message- From: [EMAIL PROTECTED] [mailto:pgsql-hackers- [EMAIL PROTECTED] On Behalf Of Gregory Maxwell Sent: Friday, September 30, 2005 7:07 PM To: Ron Peacetree Cc: Jeffrey W. Baker; pgsql-hackers@postgresql.org; pgsql- [EMAIL PROTECTED]