Re: pg_class catalog question...

On Fri, Mar 31, 2006 at 11:29:15AM -0500, Tom Lane wrote:
> "Jim C. Nasby" <jnasby@pervasive.com> writes:
> > About the only reason I use CHAR in other databases systems is when I
> > know that the field will always contain the same amount of data, ie:
> > storing a SHA1. In these cases it's silly to have a 4 byte overhead to
> > store length. I really wish CHAR in PostgreSQL worked this way, so it
> > would be a welcome addition to have a type that did work this way. In
> > fact, I'd argue that CHAR should be made to work that way, and what's
> > currently called CHAR should be renamed for those who wish to use it.
> 
> This argument falls flat when you consider that the width of a CHAR
> entry is measured in characters, not bytes, and therefore its physical
> size is not fixed even if its logical width is.

True, but in every case I've used char it was to store something that
would never be multi-byte, like a GUID, or a SHA1. Though I guess in
retrospect, what would really be handy is 'hex' datatype, that stores a
hex string (possibly with a custom format, such as a GUID) in it's
native binary format.
-- 
Jim C. Nasby, Sr. Engineering Consultant      jnasby@pervasive.com
Pervasive Software      http://pervasive.com    work: 512-231-6117
vcard: http://jim.nasby.net/pervasive.vcf       cell: 512-569-9461