Re: MySQL vs PostgreSQL.

On Fri, 11 Oct 2002, Jeff Davis wrote:

> > They also state that they have more sophisticated ALTER TABLE...
> >
> > Only usable feature in their ALTER TABLE that doesn't (yet) exist in
> > PostgreSQL was changing column order (ok, the order by in table creation
> > could be nice), and that's still almost purely cosmetic. Anyway, I could
> > have used that command yesterday. Could this be added to pgsql.
> >
>
> I agree with your message except for that statement. MySQL alter table
> provides the ability to change column types and cast the records
> automatically. I remember that feature as really the only thing from MySQL
> that I've ever missed.
>
> Of course, it's not that wonderful in theory. During development you can
> easily drop/recreate the tables and reload the test data; during production
> you don't change the data types of your attributes.
>
> But in practice, during development it's handy sometimes.

I still remember a post from somebody on the phpbuilder site that had
changed a field from varchar to date and all the dates he had got changed
to 0000-00-00.

He most unimpressed, especially since he (being typical of a lot of MySQL
users) didn't have a backup.