TUPLE SIZE HELP

Started by Thomas Swanover 25 years ago10 messages
#1Thomas Swan
tswan@olemiss.edu

I've tried doing as much reading on the mailing lists as I can on this.

The problem lies in that I'm trying to use PostgreSQL to store HTML
documents which are larger than the default tuple size of 8120 bytes. I
originally thought that the data type TEXT wasn't limited in size. Also,
through some of the postings, I came to the understanding there was a
limit, but that it was supposed to be removed.

I've gone through the source some and found where MaxTupleSize is defined,
but I'm not sure what would be acceptable values to set it to.

Can anyone offer some help?

Thanks in advance,
Thomas
-
- Thomas Swan
- Graduate Student - Computer Science
- The University of Mississippi
-
- "People can be categorized into two fundamental
- groups, those that divide people into two groups
- and those that don't."

#2B. Palmer
bpalmer@sixdegrees.com
In reply to: Thomas Swan (#1)
Re: TUPLE SIZE HELP

I've gone through the source some and found where MaxTupleSize is defined,
but I'm not sure what would be acceptable values to set it to.

Though 8k is the default tuple size, you can change that number to be
up to 32k AT COMPILE TIME. You can't, however, go above that size.
The code base doesn't support a larger size. At this time, you can
either use Large Objects or wait a bit for the TOAST project to be
finish (is there a max for that? 2G?)

- Brandon
sixdegrees.com
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#3Thomas Swan
tswan@olemiss.edu
In reply to: B. Palmer (#2)
Re: TUPLE SIZE HELP

Though 8k is the default tuple size, you can change that number to be
up to 32k AT COMPILE TIME. You can't, however, go above that size.
The code base doesn't support a larger size. At this time, you can
either use Large Objects or wait a bit for the TOAST project to be
finish (is there a max for that? 2G?)

How can I do this? Is there a -DEFINE or something?

Excuse my ignorance, there are things I SHOULD know...

Thomas

-
- Thomas Swan
- Graduate Student - Computer Science
- The University of Mississippi
-
- "People can be categorized into two fundamental
- groups, those that divide people into two groups
- and those that don't."

#4Tom Lane
tgl@sss.pgh.pa.us
In reply to: Thomas Swan (#1)
Re: TUPLE SIZE HELP

Thomas Swan <tswan@olemiss.edu> writes:

I've gone through the source some and found where MaxTupleSize is defined,
but I'm not sure what would be acceptable values to set it to.

That would be the wrong thing to change in any case. BLCKSZ in
include/config.h is the value you can twiddle.

regards, tom lane

#5Thomas Swan
tswan@olemiss.edu
In reply to: Tom Lane (#4)
Re: TUPLE SIZE HELP

That would be the wrong thing to change in any case. BLCKSZ in
include/config.h is the value you can twiddle.

Are there any plans to remove this limitation from the TEXT datatype? If
so, do you know what version we might see this in?

-
- Thomas Swan
- Graduate Student - Computer Science
- The University of Mississippi
-
- "People can be categorized into two fundamental
- groups, those that divide people into two groups
- and those that don't."

#6Noname
JanWieck@t-online.de
In reply to: Thomas Swan (#5)
Re: TUPLE SIZE HELP

Thomas Swan wrote:

That would be the wrong thing to change in any case. BLCKSZ in
include/config.h is the value you can twiddle.

Are there any plans to remove this limitation from the TEXT datatype? If
so, do you know what version we might see this in?

It is already in the current development tree and will be
shipped with the next release, scheduled for end of the year.

Jan

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# It's easier to get forgiveness for being wrong than for being right. #
# Let's break this rule - forgive me. #
#================================================== JanWieck@Yahoo.com #

#7Hannu Krosing
hannu@tm.ee
In reply to: Noname (#6)
Re: TUPLE SIZE HELP

The Hermit Hacker wrote:

On Tue, 18 Jul 2000, Jan Wieck wrote:

Thomas Swan wrote:

That would be the wrong thing to change in any case. BLCKSZ in
include/config.h is the value you can twiddle.

Are there any plans to remove this limitation from the TEXT datatype? If
so, do you know what version we might see this in?

It is already in the current development tree and will be
shipped with the next release, scheduled for end of the year.

Just a quick note ... with v7.x, you *can* use the lztext type to get by
the limitation ... its a temporary fix, but I believe that Vince is using
it for the web site for similar reasons to the original poster ...

IIRC lztext does only compression and not splitting, so it just gets you
so far ...

-------
Hannu

#8The Hermit Hacker
scrappy@hub.org
In reply to: Noname (#6)
Re: TUPLE SIZE HELP

On Tue, 18 Jul 2000, Jan Wieck wrote:

Thomas Swan wrote:

That would be the wrong thing to change in any case. BLCKSZ in
include/config.h is the value you can twiddle.

Are there any plans to remove this limitation from the TEXT datatype? If
so, do you know what version we might see this in?

It is already in the current development tree and will be
shipped with the next release, scheduled for end of the year.

Just a quick note ... with v7.x, you *can* use the lztext type to get by
the limitation ... its a temporary fix, but I believe that Vince is using
it for the web site for similar reasons to the original poster ...

#9Vince Vielhaber
vev@michvhf.com
In reply to: The Hermit Hacker (#8)
Re: TUPLE SIZE HELP

On Tue, 18 Jul 2000, The Hermit Hacker wrote:

On Tue, 18 Jul 2000, Jan Wieck wrote:

Thomas Swan wrote:

That would be the wrong thing to change in any case. BLCKSZ in
include/config.h is the value you can twiddle.

Are there any plans to remove this limitation from the TEXT datatype? If
so, do you know what version we might see this in?

It is already in the current development tree and will be
shipped with the next release, scheduled for end of the year.

Just a quick note ... with v7.x, you *can* use the lztext type to get by
the limitation ... its a temporary fix, but I believe that Vince is using
it for the web site for similar reasons to the original poster ...

You are correct. The guide now fits into one tuple.

Vince.
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#10The Hermit Hacker
scrappy@hub.org
In reply to: Hannu Krosing (#7)
Re: TUPLE SIZE HELP

On Wed, 19 Jul 2000, Hannu Krosing wrote:

The Hermit Hacker wrote:

On Tue, 18 Jul 2000, Jan Wieck wrote:

Thomas Swan wrote:

That would be the wrong thing to change in any case. BLCKSZ in
include/config.h is the value you can twiddle.

Are there any plans to remove this limitation from the TEXT datatype? If
so, do you know what version we might see this in?

It is already in the current development tree and will be
shipped with the next release, scheduled for end of the year.

Just a quick note ... with v7.x, you *can* use the lztext type to get by
the limitation ... its a temporary fix, but I believe that Vince is using
it for the web site for similar reasons to the original poster ...

IIRC lztext does only compression and not splitting, so it just gets you
so far ...

Correct ...