Tuple size limits and upgrading

Started by Gordan Bobicover 25 years ago4 messagesgeneral
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#1Gordan Bobic
gordan@freeuk.com

Hi!

I've got a bit of a problem with tuple size limits. They seem to be limited
to 8K, which is not enough for me, in the current application. Ideally, I'd
like to bump this up to at least 256K, although 512K would be nice. This is
for the purpose of storing large text fields, although it's usefulness
might be extended for storing binary data as well (e.g. large images).

Is there a way to allow records (tuples) to have arbitrary size?

A fair majority of the text files I am storing in the database fits into
records despite the 8K limit. However, there is a substantial number of
those that don't. The biggest ones can go up to 512KB and beyond, but this
is somewhat uncommon.

I have read in the archives that this can be modified by changing a few
parameters and re-compiling. What is the limit to which the record size can
be increased? Does this setting seriously hammer performance (even if there
are only comparatively few records of this size)?

The problem is that I would like to keep the way things are working,
including directory structures, and I am not sure how to do this if I
re-compile from source, as that will put everything into /usr/local.

I am running RH Linux 6.2, upgraded to PGSQL 7.0.1, and files are in
/var/lib/pgsql and /usr/lib/pgsql, and non-/usr/local locations.

How can I upgrade to a customized version of 7.0.3 while keeping all the
files in the same place? I know I can use the SRPM distribution, but just
doing rpm --rebuild doesn't let me tweak the parameter in need to change.

Can anybody suggest a way of doing this?

Thanks.

Gordan

#2Igor Roboul
igor@raduga.dyndns.org
In reply to: Gordan Bobic (#1)
Re: Tuple size limits and upgrading

On Tue, Nov 28, 2000 at 10:36:20AM -0000, Gordan Bobic wrote:

like to bump this up to at least 256K, although 512K would be nice. This is
for the purpose of storing large text fields, although it's usefulness

If you don't need make index on this text field, and indexing BIG text
is not very good, you can store big text into BLOB

might be extended for storing binary data as well (e.g. large images).

For binary data use BLOBs

--
Igor' Robul', Unix System Administrator & Programmer @ sanatorium "Raduga",
Sochi, Russia
http://www.brainbench.com/transcript.jsp?pid=304744

#3Gordan Bobic
gordan@freeuk.com
In reply to: Gordan Bobic (#1)
Re: Tuple size limits and upgrading

Sorry for replying to my own email, but I've just stumbled upon an article
that seems to imply that v7.1 will support unlimited record lengths. Is
this the case? When is v7.1 due for release? Is a beta available?

Thanks.

Gordan

----- Original Message -----
From: "Gordan Bobic" <gordan@freeuk.com>
To: <pgsql-general@postgresql.org>
Sent: Tuesday, November 28, 2000 10:36 AM
Subject: [GENERAL] Tuple size limits and upgrading

Hi!

I've got a bit of a problem with tuple size limits. They seem to be

limited

to 8K, which is not enough for me, in the current application. Ideally,

I'd

like to bump this up to at least 256K, although 512K would be nice. This

is

for the purpose of storing large text fields, although it's usefulness
might be extended for storing binary data as well (e.g. large images).

Is there a way to allow records (tuples) to have arbitrary size?

A fair majority of the text files I am storing in the database fits into
records despite the 8K limit. However, there is a substantial number of
those that don't. The biggest ones can go up to 512KB and beyond, but

this

is somewhat uncommon.

I have read in the archives that this can be modified by changing a few
parameters and re-compiling. What is the limit to which the record size

can

be increased? Does this setting seriously hammer performance (even if

there

Show quoted text

are only comparatively few records of this size)?

The problem is that I would like to keep the way things are working,
including directory structures, and I am not sure how to do this if I
re-compile from source, as that will put everything into /usr/local.

I am running RH Linux 6.2, upgraded to PGSQL 7.0.1, and files are in
/var/lib/pgsql and /usr/lib/pgsql, and non-/usr/local locations.

How can I upgrade to a customized version of 7.0.3 while keeping all the
files in the same place? I know I can use the SRPM distribution, but just
doing rpm --rebuild doesn't let me tweak the parameter in need to change.

Can anybody suggest a way of doing this?

Thanks.

Gordan

#4Martin A. Marques
martin@math.unl.edu.ar
In reply to: Gordan Bobic (#3)
Re: Tuple size limits and upgrading

On Tuesday 28 November 2000 10:56, Gordan Bobic wrote:

Sorry for replying to my own email, but I've just stumbled upon an article
that seems to imply that v7.1 will support unlimited record lengths. Is
this the case? When is v7.1 due for release? Is a beta available?

The last thing I heard was that it was scheduled to be out in February.
You can download a pre-beta version via CVS. Check the postgres web site.

Saludos... ;-)

--
"And I'm happy, because you make me feel good, about me." - Melvin Udall
-----------------------------------------------------------------
Mart�n Marqu�s email: martin@math.unl.edu.ar
Santa Fe - Argentina http://math.unl.edu.ar/~martin/
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