> -----Original Message-----
> From: Alex Satrapa [mailto:alex@lintelsys.com.au]
> Sent: Tuesday, December 16, 2003 7:24 PM
> To: pgsql-general@postgresql.org
> Subject: Re: [GENERAL] Any commercial shopping cart packages
> using postgresql?
>
>
> Alex Satrapa wrote:
> > I'm currently exploring the Zelerate AllCommerce system
> > http://allcommerce.sourceforge.net
>
> Ick... this product is *so* the poster child of the MySQL generation:
>
> #
> # Table structure for table 'addresses'
> #
> CREATE TABLE addresses (
> objid varchar(20) DEFAULT '' NOT NULL,
> objclass varchar(20) DEFAULT '' NOT NULL,
> objtype varchar(20) DEFAULT '' NOT NULL,
> ...
> PRIMARY KEY objid
> );
>
> No foreign keys! Look at all those "DEFAULT '' NOT NULL"
> columns! What
> are they thinking?
The no foreign keys thing means RI is out the window, of course. A sea
of tables, floating in a soupy database fog of danger.
But as for the DEFAULT '' NOT NULL entries, CODD and Date eventually
decided that NULL data was a big mistake.
While SQL programmers are used to it, most end users with slim SQL
familiarity will be pretty shocked when:
SELECT COUNT(*) FROM addresses WHERE <column> = 'some_constant'
Added with
SELECT COUNT(*) FROM addresses WHERE NOT <column> =
'some_constant'
Is not equal to
SELECT COUNT(*) FROM addresses
I tend to agree that every column should have a default and not be
allowed to become NULL. Just to keep end-user astonishment at a
minimum.
> As penance for suggesting this product, I will clean up the
> SQL and at
> least post my experiences with installing and using this product on
> PostgreSQL.
>
>
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