Re: Re: DB porting questions...

On Tue, Apr 17, 2001 at 11:45:08AM -0400, Vivek Khera wrote:

> I'm just starting, but I've got two questions. I've found some
> scripts out there that claim to do the conversion of the SQL create
> commands, but none does the right thing it seems.

Please help better these scripts then. That way you're helping
everybody, including yourself (with gained experience).

> I've now found out how to handle the timestamp for insert times and
> how to do auto-increment fields.

> My unsderstanding of MySQL's enum type is to use something like this
> in postgres:
>
> owner_status varchar(9) check
> (owner_status in ('pending','active','suspended'))
> NOT NULL default 'pending',

That's standard SQL, which PostgreSQL supports. You could use this
same statement in Oracle, or other compliant DBs.

> Currently in MySQL I have this:
>
> owner_features set('premium','haveccinfo') default NULL,
>
> for example. Some other fiels may have about 20 such values, and
> MySQL lets me keep these in 3 bytes as a bit-field behind the scenes.

MySQL is helping you get into trouble by giving you a non-standard way
to do something for which there's a standard.

> >From what I see, my choice in Postgres is to store this as a
> comma-separated string and let my application work as before.

For columns with more than a couple values, I'd suggest normalizing
your tables. In the "owner_features" case above, you could do something
like:

create table owner_features (
feature_id serial
constraint owner_features_pk primary key,
feature varchar(30)
constraint owner_features_feature_nn not null
);

Then your table would just reference owner_features.feature_id. Much
cleaner, especially for tables with lots of cases.

> Does anyone have a script that actually handles properly doing auto
> increments with the SERIAL type, and does the set/enum conversions?

What do you mean by "propely doing auto increments"? What's the
problem you are having?

-Roberto
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