Re: effective SELECT from child tables

On Sat, Oct 01, 2005 at 02:13:09PM +0200, Martijn van Oosterhout wrote:
> On Fri, Sep 30, 2005 at 06:30:10PM -0500, Jim C. Nasby wrote:
> > On Wed, Sep 28, 2005 at 07:25:46PM +0100, Simon Riggs wrote:
> > > Include the Discriminator as a column in A and it will be inherited by
> > > all A1, A2, A3. 
> > > e.g. concrete_class    char(1) not null
> > <snip>
> > > This will add 1 byte per row in your superclass... and requires no
> > 
> > I thought char was actually stored variable-length...? I know there's a
> > type that actually acts like char does on most databases, but I can't
> > remember what it is off-hand (it should be mentioned in docs 8.3...)
> 
> IIRC, this is the difference between "char" and char(1). The latter is
> variable length and can store any character per current encoding, hence
> the variable length. "char" on the other hand is a one byte (presumably
> ASCII) character. It's used mainly in the system catalogs...

According to the docs, char == char(1).
-- 
Jim C. Nasby, Sr. Engineering Consultant      jnasby@pervasive.com
Pervasive Software      http://pervasive.com    work: 512-231-6117
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