Re: Reducing data type space usage - Mailing list pgsql-hackers

From Bruce Momjian
Subject Re: Reducing data type space usage
Date
Msg-id 200609161849.k8GInlm25195@momjian.us
Whole thread Raw
In response to Re: Reducing data type space usage  (Hannu Krosing <hannu@skype.net>)
List pgsql-hackers
Hannu Krosing wrote:
> ?hel kenal p?eval, R, 2006-09-15 kell 19:18, kirjutas Tom Lane:
> > Bruce Momjian <bruce@momjian.us> writes:
> > > Tom Lane wrote:
> > >> No, it'll be a 1-byte header with length indicating that no bytes
> > >> follow,
> > 
> > > Well, in my idea, 10000001 would be 0x01.  I was going to use the
> > > remaining 7 bits for the 7-bit ascii value.
> > 
> > Huh?  I thought you said 00000001 would be 0x01, that is, high bit
> > clear means a single byte containing an ASCII character. 
> 
> why not go all the way, and do utf-7 encoded header if hi bit is set ?
> 
> or just always have an utf-8 encoded header.

This is a special zero-length header case.  We only have one byte. 
Doing a utf8 length call to span to the next column is too expensive.

--  Bruce Momjian   bruce@momjian.us EnterpriseDB    http://www.enterprisedb.com
 + If your life is a hard drive, Christ can be your backup. +


pgsql-hackers by date:

Previous
From: Hannu Krosing
Date:
Subject: Re: Reducing data type space usage
Next
From: Bruce Momjian
Date:
Subject: Re: Reducing data type space usage