Re: [HACKERS] create temp table .. on commit delete rows

2006-10-12 Thread Bruce Momjian
Tom Lane wrote:
> Bruce Momjian <[EMAIL PROTECTED]> writes:
> > David Fetter wrote:
> >>> Should something notice and raise a warning when people create a
> >>> TEMP table and have AUTOCOMMIT on?
> 
> > Added to TODO:
> > o Issue a notice if CREATE TABLE ... ON COMMIT { DELETE ROWS |
> >   DROP } is issued outside a multi-statement transaction
> 
> That is *not* what was suggested, and it doesn't seem very useful.  The
> problem really comes when one uses a temp table in autocommit mode, not
> at creation time.
> 
> The problem with the original suggestion is that the backend can't do it
> because AUTOCOMMIT is a notion that exists only in the client-side code.
> And the client can't do it very well because it'd have to parse SQL
> commands, and even with that it wouldn't see CREATE TEMP TABLE commands
> issued inside functions.

Ewe.  Yea, I will just remove it.  We can't issue a warning easily.

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  Bruce Momjian   [EMAIL PROTECTED]
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Re: [HACKERS] create temp table .. on commit delete rows

2006-10-12 Thread Tom Lane
Bruce Momjian <[EMAIL PROTECTED]> writes:
> David Fetter wrote:
>>> Should something notice and raise a warning when people create a
>>> TEMP table and have AUTOCOMMIT on?

> Added to TODO:
> o Issue a notice if CREATE TABLE ... ON COMMIT { DELETE ROWS |
>   DROP } is issued outside a multi-statement transaction

That is *not* what was suggested, and it doesn't seem very useful.  The
problem really comes when one uses a temp table in autocommit mode, not
at creation time.

The problem with the original suggestion is that the backend can't do it
because AUTOCOMMIT is a notion that exists only in the client-side code.
And the client can't do it very well because it'd have to parse SQL
commands, and even with that it wouldn't see CREATE TEMP TABLE commands
issued inside functions.

regards, tom lane

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Re: [HACKERS] create temp table .. on commit delete rows

2006-10-12 Thread Bruce Momjian
David Fetter wrote:
> On Thu, Oct 12, 2006 at 02:07:28PM -0500, Jim C. Nasby wrote:
> > On Thu, Oct 12, 2006 at 12:01:12PM -0700, David Fetter wrote:
> > > On Thu, Oct 12, 2006 at 03:51:39PM +0400, Teodor Sigaev wrote:
> > > > >You're running in auto-commit, mode.  An implicit commit
> > > > >happens after this statement.  Which clears the table.  Looks
> > > > >right to me.
> > > > 
> > > > Oops, I see
> > > 
> > > Should something notice and raise a warning when people create a
> > > TEMP table and have AUTOCOMMIT on?
> > 
> > Maybe if ON COMMIT is set to DELETE ROWS or DROP...
> 
> Sounds good :)

Added to TODO:

o Issue a notice if CREATE TABLE ... ON COMMIT { DELETE ROWS |
  DROP } is issued outside a multi-statement transaction

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  Bruce Momjian   [EMAIL PROTECTED]
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Re: [HACKERS] create temp table .. on commit delete rows

2006-10-12 Thread David Fetter
On Thu, Oct 12, 2006 at 02:07:28PM -0500, Jim C. Nasby wrote:
> On Thu, Oct 12, 2006 at 12:01:12PM -0700, David Fetter wrote:
> > On Thu, Oct 12, 2006 at 03:51:39PM +0400, Teodor Sigaev wrote:
> > > >You're running in auto-commit, mode.  An implicit commit
> > > >happens after this statement.  Which clears the table.  Looks
> > > >right to me.
> > > 
> > > Oops, I see
> > 
> > Should something notice and raise a warning when people create a
> > TEMP table and have AUTOCOMMIT on?
> 
> Maybe if ON COMMIT is set to DELETE ROWS or DROP...

Sounds good :)

Cheers,
D
-- 
David Fetter <[EMAIL PROTECTED]> http://fetter.org/
phone: +1 415 235 3778AIM: dfetter666
  Skype: davidfetter

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Re: [HACKERS] create temp table .. on commit delete rows

2006-10-12 Thread Jim C. Nasby
On Thu, Oct 12, 2006 at 12:01:12PM -0700, David Fetter wrote:
> On Thu, Oct 12, 2006 at 03:51:39PM +0400, Teodor Sigaev wrote:
> > >You're running in auto-commit, mode.  An implicit commit happens
> > >after this statement.  Which clears the table.  Looks right to me.
> > 
> > Oops, I see
> 
> Should something notice and raise a warning when people create a TEMP
> table and have AUTOCOMMIT on?

Maybe if ON COMMIT is set to DELETE ROWS or DROP...
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Re: [HACKERS] create temp table .. on commit delete rows

2006-10-12 Thread David Fetter
On Thu, Oct 12, 2006 at 03:51:39PM +0400, Teodor Sigaev wrote:
> >You're running in auto-commit, mode.  An implicit commit happens
> >after this statement.  Which clears the table.  Looks right to me.
> 
> Oops, I see

Should something notice and raise a warning when people create a TEMP
table and have AUTOCOMMIT on?

Cheers,
D
-- 
David Fetter <[EMAIL PROTECTED]> http://fetter.org/
phone: +1 415 235 3778AIM: dfetter666
  Skype: davidfetter

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Re: [HACKERS] create temp table .. on commit delete rows

2006-10-12 Thread Teodor Sigaev
You're running in auto-commit, mode. An implicit commit happens after 
this statement. Which clears the table.

> Looks right to me.

Oops, I see

--
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Re: [HACKERS] create temp table .. on commit delete rows

2006-10-12 Thread Heikki Linnakangas

Teodor Sigaev wrote:

2)
# insert into a values(1);


You're running in auto-commit, mode. An implicit commit happens after 
this statement. Which clears the table.



# begin;
# insert into a values(2);
# rollback;
# select * from a;
 a
---
(0 rows)

It seems to me that 1) is good, but 2) makes some strange, unpredictable 
result...


Looks right to me.

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  EnterpriseDB   http://www.enterprisedb.com

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[HACKERS] create temp table .. on commit delete rows

2006-10-12 Thread Teodor Sigaev

1)
# create temp table a ( a int ) without oids on commit delete rows;
# insert into a values(1);
# begin;
# insert into a values(2);
# commit;
# select * from a;
 a
---
(0 rows)

2)
# insert into a values(1);
# begin;
# insert into a values(2);
# rollback;
# select * from a;
 a
---
(0 rows)

It seems to me that 1) is good, but 2) makes some strange, unpredictable 
result...

--
Teodor Sigaev   E-mail: [EMAIL PROTECTED]
   WWW: http://www.sigaev.ru/

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