Re: PostGreSQL and zlib - Mailing list pgsql-hackers

From Hubert FONGARNAND
Subject Re: PostGreSQL and zlib
Date
Msg-id 1193312997.10966.8.camel@hublinux.fidudev.fr
Whole thread Raw
In response to Re: PostGreSQL and zlib  (Gregory Stark <stark@enterprisedb.com>)
Responses Re: PostGreSQL and zlib
List pgsql-hackers
The problem is that for TOAST columns :
"The compression technique used is a fairly simple and very fast member of the LZ family of compression techniques. See src/backend/utils/adt/pg_lzcompress.c for the details."
With such function you could choose you compression algorithm and compression level...

Another question : does this TOAST code works for all type of data, like TEXT (in our case)


Le jeudi 25 octobre 2007 à 11:03 +0100, Gregory Stark a écrit :
"Hubert FONGARNAND" <informatique.internet@fiducial.fr> writes:

> I'm sure it's very easy to implement as a C function that would call zlib
>
> Is there already an implementation of such things?

Not that I'm aware though you might look at pgcrypto. Good crypto has to
compress first so there may be a possibility of just doing the compression.

Postgres also will automatically try to compress data like byteas if the
record is larger than 2kB (1/4 of the block size if you've changed the block
size). So you may not have to do anything if you're just looking to save space
on disk.

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