Martijn van Oosterhout (kl...@svana.org)

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Martijn van Oosterhout

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kl...@svana.org

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2216	total
9	in PostgreSQL - Admin
2	in PostgreSQL - Advocacy
10	in PostgreSQL - Bugs
1	in PostgreSQL - Docs
2180	in PostgreSQL - General
3	in PostgreSQL - Interfaces
2	in PostgreSQL - Novice
33	in PostgreSQL - Performance
13	in PostgreSQL - SQL

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1) Martijn van Oosterhout Re: [GENERAL] Regex query not using index

+1 vote

WHERE fielda = fielda will only match non-null rows... Have a nice day,

PostgreSQL - General

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On Wed, Feb 20, 2008 at 12:56:54AM -0800, Postgres User wrote:
> a final question: why does this syntax do a seq scan + filter:
> 
> select * from tablea where fielda = fielda   -or-  select * from
> tablea where fielda in (fielda)
> 
> while this syntax results in no filter, seq scan only
> 
> select * from tablea where 1 = 1
> 
> it seems that both where clauses should be ignored by the optimizer-
> or am i missing something

WHERE fielda = fielda will only match non-null rows...

Have a nice day,
-- 
Martijn van Oosterhout   <kleptog@svana.org>   http://svana.org/kleptog/
> Those who make peaceful revolution impossible will make violent revolution inevitable.
>  -- John F Kennedy -----BEGIN PGP SIGNATURE-----
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2) Martijn van Oosterhout Re: [GENERAL] out-of-line (TOAST) storage ineffective when loading from dump?

+1 vote

I should hope not. I don't think any modern filesystem works that way. There's a reason why there's...

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On Tue, Feb 19, 2008 at 03:55:27PM +0600, Markus Bertheau wrote:
> > The "toast" pages are stored in a separate table - see manual for
> > details. There's a whole chapter (53.2) on this.
> 
> Yes, but I assume that on disk the pages will be laid out sequentially
> - not intentionally so, of course. See below.

I should hope not. I don't think any modern filesystem works that way.
There's a reason why there's no defragmentation tool for many
filesystems, it's not an issue these days.

Have a nice day,
-- 
Martijn van Oosterhout   <kleptog@svana.org>   http://svana.org/kleptog/
> Those who make peaceful revolution impossible will make violent revolution inevitable.
>  -- John F Kennedy -----BEGIN PGP SIGNATURE-----
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3) Martijn van Oosterhout Re: [GENERAL] Some Autovacuum Questions

+1 vote

Obviously 8.1.11, given the upgrade should only take moments... Have a nice day,

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On Tue, Feb 12, 2008 at 04:13:33PM +0100, Thomas Chille wrote:
> We are still using 8.1.4 because a database upgrade for us and our
> product is a hefty step wich involves a lot of customer databases. But
> if it could help we consider to upgrade to 8.1.11 or 8.3. What would u
> suggest?

Obviously 8.1.11, given the upgrade should only take moments...

Have a nice day,
-- 
Martijn van Oosterhout   <kleptog@svana.org>   http://svana.org/kleptog/
> Those who make peaceful revolution impossible will make violent revolution inevitable.
>  -- John F Kennedy -----BEGIN PGP SIGNATURE-----
Version: GnuPG v1.4.1 (GNU/Linux)

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4) Martijn van Oosterhout Re: [GENERAL] SELECT CAST(123 AS char) -> 1

+1 vote

Does it have to be a cast? I would've thought to_char() might work more reliably across databases....

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On Mon, Feb 11, 2008 at 10:36:49PM -0700, Ken Johanson wrote:
> For sake of interoperability (and using an API that requires String-type 
> hashtable keys), I'm trying to find a single CAST (int -> var/char) 
> syntax that works between the most databases. Only char seems to be a 
> candidate, but in 8.3 casting from an integer outputs only the first char...

Does it have to be a cast? I would've thought to_char() might work more
reliably across databases.

Have a nice day,
-- 
Martijn van Oosterhout   <kleptog@svana.org>   http://svana.org/kleptog/
> Those who make peaceful revolution impossible will make violent revolution inevitable.
>  -- John F Kennedy -----BEGIN PGP SIGNATURE-----
Version: GnuPG v1.4.1 (GNU/Linux)

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5) Martijn van Oosterhout Re: [GENERAL] oids

+1 vote

Nope. Have a nice day,

PostgreSQL - General

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On Mon, Feb 11, 2008 at 10:15:40AM -0800, Bob Pawley wrote:
> I'm running Postgresql 8.2 on Windows.
> 
> If I create a table 'without oids' are oids still in use behind the scenes??

Nope.

Have a nice day,
-- 
Martijn van Oosterhout   <kleptog@svana.org>   http://svana.org/kleptog/
> Those who make peaceful revolution impossible will make violent revolution inevitable.
>  -- John F Kennedy -----BEGIN PGP SIGNATURE-----
Version: GnuPG v1.4.1 (GNU/Linux)

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