Horton

Thread

  1. Re: disabling OIDs?

    Mark Dexter <mdexter@dexterchaney.com> — 2004-12-13T20:13:27Z

    I don't know why they use OID's for cursors.  But I do know that if you
run a trace the SQL that creates the cursor uses OID's, 
so it doesn't work if the table is created without OID's.  Also, if you
want to have updateable cursors against views (i.e., a view with rules
for INSERT, UPDATE, and DELETE), you must name the OID and CTID as
columns in the view.   Again, we learned this the hard way.  Mark Dexter

-----Original Message-----
From: gsstark@mit.edu [mailto:gsstark@mit.edu] 
Sent: Monday, December 13, 2004 12:06 PM
To: Mark Dexter
Cc: pgsql-general@postgresql.org; gsstark@mit.edu
Subject: Re: disabling OIDs?



"Mark Dexter" <MDEXTER@dexterchaney.com> writes:

> > For what it's worth, OIDs are required if you ever want to use 
> > updateable cursors with the ODBC driver.  We discovered this the 
> > hard way.  Mark Dexter

That's unfortunate. Is it because it's difficult to track down the
primary key of the table? Is it any easier to track down the primary key
of the table in 8.0? It would be much better if it checked the primary
key and used that instead of OIDs.

Though I'm unclear implementing "updateable cursors" in the client-end
is really a good idea. I suppose it's nice if you understand the
limitations inherent.

-- 
greg

  2. Re: SELECTing on age

    Kall, Bruce A. <kall@mayo.edu> — 2004-12-13T21:15:46Z

    I'm attempting to select records from my postgresql database using php
based on whether someone is at least 17 years old on the date of a 
particular visit.

My sql is:

$db_sql = "SELECT * from list WHERE ((visit_date - birth_date) >= 17)'"
$db_result = db_exec($db_sql)
$num = pg_num_rows($db_result);
for($i = 0; $i < $num; $i++)
   {
   $data = pg_num_rows($db_result,$i)
   $visit_date = $data["visit_date"];
   $birth_date = $data["birth_date"];
   echo "Visit date[$visit_date]  Birth date[$birth_date]";
   }

The problem I'm having is that the the query is returning results for 
some people with ages < 17 (most of them are correct, just a couple of 
incorrect ones interspersed with the correct ones that are over 17)?

For example, my output contains:

Visit date[2004-07-14]  Birth date[2004-02-19]
and
Visit date[2004-08-11]  Birth date[2003-04-21]

which are clearly people who are < 17.


Any suggestions on how to track down this problem or rework the query so 
it always works correctly?  If I reverse the query and look for people < 
17, I don't get any that are older than 17.

Thanks,
Bruce

  3. Re: SELECTing on age

    Scott Marlowe <smarlowe@g2switchworks.com> — 2004-12-13T21:39:25Z

    On Mon, 2004-12-13 at 15:15, Kall, Bruce A. wrote:
> I'm attempting to select records from my postgresql database using php
> based on whether someone is at least 17 years old on the date of a 
> particular visit.
> 
> My sql is:
> 
> $db_sql = "SELECT * from list WHERE ((visit_date - birth_date) >= 17)'"
> $db_result = db_exec($db_sql)
> $num = pg_num_rows($db_result);
> for($i = 0; $i < $num; $i++)
>    {
>    $data = pg_num_rows($db_result,$i)
>    $visit_date = $data["visit_date"];
>    $birth_date = $data["birth_date"];
>    echo "Visit date[$visit_date]  Birth date[$birth_date]";
>    }
> 
> The problem I'm having is that the the query is returning results for 
> some people with ages < 17 (most of them are correct, just a couple of 
> incorrect ones interspersed with the correct ones that are over 17)?
> 
> For example, my output contains:
> 
> Visit date[2004-07-14]  Birth date[2004-02-19]
> and
> Visit date[2004-08-11]  Birth date[2003-04-21]
> 
> which are clearly people who are < 17.

Check out what this query tells you:

postgres=# select ('2004-07-31'::date-'2004-07-01'::date);
 ?column?
----------
       30


Notice how the output of subtracting one date from another is an int for
the number of days?  A better way would be:

select * from table1 where dt <now()-'17 years'::interval;

  4. increasing max_connections on freebsd

    Hengki Suhartoyo <hengman03@yahoo.com> — 2004-12-14T10:46:44Z

    Hello...

I want to increase my max_connections up to 128
connections, but I got that I need to recompile my
kernel. I'm newbie in postgresql and freebsd. How to
increase max_connections and recompile freebsd kernel.

Help Me please.....

Thank's

__________________________________________________
Do You Yahoo!?
Tired of spam?  Yahoo! Mail has the best spam protection around 
http://mail.yahoo.com

  5. Re: increasing max_connections on freebsd

    Frank D. Engel, Jr. <fde101@fjrhome.net> — 2004-12-14T15:01:47Z

    You might want to check some of these sites:

http://www.silverwraith.com/papers/freebsd-kernel.php
http://www.freebsd.org/doc/en_US.ISO8859-1/books/handbook/ 
kernelconfig.html


Anyone have a clue why he would need to recompile his kernel for this,  
though?

On Dec 14, 2004, at 5:46 AM, Hengki Suhartoyo wrote:

> Hello...
>
> I want to increase my max_connections up to 128
> connections, but I got that I need to recompile my
> kernel. I'm newbie in postgresql and freebsd. How to
> increase max_connections and recompile freebsd kernel.
>
> Help Me please.....
>
> Thank's
>
> __________________________________________________
> Do You Yahoo!?
> Tired of spam?  Yahoo! Mail has the best spam protection around
> http://mail.yahoo.com
>
> ---------------------------(end of  
> broadcast)---------------------------
> TIP 3: if posting/reading through Usenet, please send an appropriate
>       subscribe-nomail command to majordomo@postgresql.org so that your
>       message can get through to the mailing list cleanly
>
>
-----------------------------------------------------------
Frank D. Engel, Jr.  <fde101@fjrhome.net>

$ ln -s /usr/share/kjvbible /usr/manual
$ true | cat /usr/manual | grep "John 3:16"
John 3:16 For God so loved the world, that he gave his only begotten  
Son, that whosoever believeth in him should not perish, but have  
everlasting life.
$



___________________________________________________________
$0 Web Hosting with up to 120MB web space, 1000 MB Transfer
10 Personalized POP and Web E-mail Accounts, and much more.
Signup at www.doteasy.com

  6. Re: increasing max_connections on freebsd

    Michael Fuhr <mike@fuhr.org> — 2004-12-14T16:53:39Z

    On Tue, Dec 14, 2004 at 10:01:47AM -0500, Frank D. Engel, Jr. wrote:
> On Dec 14, 2004, at 5:46 AM, Hengki Suhartoyo wrote:
> >
> >I want to increase my max_connections up to 128
> >connections, but I got that I need to recompile my
> >kernel. I'm newbie in postgresql and freebsd. How to
> >increase max_connections and recompile freebsd kernel.
>
> You might want to check some of these sites:
> 
> http://www.silverwraith.com/papers/freebsd-kernel.php
> http://www.freebsd.org/doc/en_US.ISO8859-1/books/handbook/ 
> kernelconfig.html
> 
> Anyone have a clue why he would need to recompile his kernel for this,  
> though?

The error probably says something about not having enough shared
memory or semaphores.  On FreeBSD some IPC settings can be configured
via sysctl but others might need to be built into the kernel.  For
example, on FreeBSD 4, trying to set kern.ipc.semmni or kern.ipc.semmns
with sysctl fails, saying that the OID is read-only.

-- 
Michael Fuhr
http://www.fuhr.org/~mfuhr/

  7. Re: increasing max_connections on freebsd

    Christian Kratzer <ck-lists@cksoft.de> — 2004-12-14T17:34:05Z

    On Tue, 14 Dec 2004, Michael Fuhr wrote:

> On Tue, Dec 14, 2004 at 10:01:47AM -0500, Frank D. Engel, Jr. wrote:
[snipp]
> The error probably says something about not having enough shared
> memory or semaphores.  On FreeBSD some IPC settings can be configured
> via sysctl but others might need to be built into the kernel.  For
> example, on FreeBSD 4, trying to set kern.ipc.semmni or kern.ipc.semmns
> with sysctl fails, saying that the OID is read-only.

At least on FreeBSD 5.x there is no need to build a customer kernel.
The following can be set in /boot/loader.conf

 	# defaults for FreeBSD are as follows
 	# SEMMNI=10, # of semaphore identifiers
 	# SEMMNS=60, # of semaphores in system
 	# SEMUME=10, max # of undo entries per process
 	# SEMMNU=30, # of undo structures in system
 	kern.ipc.semmni=40
 	kern.ipc.semmns=240
 	kern.ipc.semume=40
 	kern.ipc.semmnu=120

these will be set on boot.

Greetings
Christian

-- 
Christian Kratzer                       ck@cksoft.de
CK Software GmbH                        http://www.cksoft.de/
Phone: +49 7452 889 135                 Fax: +49 7452 889 136

  8. Re: increasing max_connections on freebsd

    Michael Fuhr <mike@fuhr.org> — 2004-12-14T18:15:40Z

    On Tue, Dec 14, 2004 at 06:34:05PM +0100, Christian Kratzer wrote:
> 
> At least on FreeBSD 5.x there is no need to build a customer kernel.
> The following can be set in /boot/loader.conf

I forgot about /boot/loader.conf.  If I get a chance I'll check if
the settings you posted also work in FreeBSD 4.  Thanks.

-- 
Michael Fuhr
http://www.fuhr.org/~mfuhr/

  9. Re: increasing max_connections on freebsd

    Vivek Khera <khera@kcilink.com> — 2004-12-22T17:18:11Z

    >>>>> "MF" == Michael Fuhr <mike@fuhr.org> writes:

MF> On Tue, Dec 14, 2004 at 06:34:05PM +0100, Christian Kratzer wrote:
>> 
>> At least on FreeBSD 5.x there is no need to build a customer kernel.
>> The following can be set in /boot/loader.conf

MF> I forgot about /boot/loader.conf.  If I get a chance I'll check if
MF> the settings you posted also work in FreeBSD 4.  Thanks.

Yes, they do.  You can also bump maxfiles if necessary via a sysctl.

-- 
=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
Vivek Khera, Ph.D.                Khera Communications, Inc.
Internet: khera@kciLink.com       Rockville, MD  +1-301-869-4449 x806
AIM: vivekkhera Y!: vivek_khera   http://www.khera.org/~vivek/