Re: Implementation of boolean types.

dawn wrote:
> Marshall Spight wrote:
> > dawn wrote:
> > > Marshall Spight wrote:
> > >
> > > This is one of several features where those attempting to implement
> > > relational theory took what was working in databases in the 70's (such
> > > as 2VL) and mucked it up, contributing to greater cost of ownership for
> > > data-centric applications.
> >
> > Hmmm. I detect that perhaps you are trying to identify this issue
> > as being somehow a consequence of RM? If so I would not agree;
> > the issues are independent.
>
> Even if current RM theory accomodates 2VL, is it historically
> inaccurate for me to suggest that before Oracle and other SQL-DBMS
> products became popular most developers working with stored data were
> using 2VL, putting ^000 or low-values or some such in "empty" fields?
> I admit that I did not research it, I just lived it and certainly not
> all of it. I think of SQL as bringing the 3VL into popularity, but I
> could be wrong. Attempts to implement the RM have been almost
> exclusively with SQL-DBMS's, so practically speaking it is the products
> that stem from the RM that have brought this on, whether they needed to
> (and we know they didn't) or not.

If you're proposing that SQL is the thing that popularized 3VL, I won't disagree. (I don't have any particular information on this topic.) But if you're proposing that any RM-based system will necessarily have 3VL, then I disagree. It's entirely possible to have a relational system with vanilla 2VL.

> > I don't think I'd agree with this either. SQL needs to be replaced,
> > not fixed,
>
> Complete agreement on that point.

Whee!

> > and the XML-family of technologies are fundamentally
> > flawed.
>
> I agree with that too. In fact, all models and all products are
> flawed, but some are more useful than others, right?

Sure, I guess. Maybe "limited" is a better word than flawed here.

> > I don't think any "data management" system that doesn't
> > have a type system or a schema in version one is going to go anywhere.
>
> I think you might have to eat those words, but we shall see.

You're anti-static typing then? Don't tell me you're anti-schema?! (Gasp!) Seriously, though, looking back at my original wording, I suppose I should have said "anywhere useful." I find it hard to imagine how anyone can advocate data management without a type system and without a schema.

> > You can't retrofit these things; they have to be designed in from
> > the start.
>
> Certainly preferred and there will definitely always be flaws, but I
> don't think we are too far off from significant changes in the database
> world and XML will surely play I roll.

It'll be sad if it does. But you may be right.

> > (Yes, I know XML now has various ways to specify schema,
> > with at least DTD and XMLSchema. [Does anyone anywhere think they
> > are good?]
>
> Not I, brother.
>
> > Reminds me of the old saw about a man with two watches.)
>
> I must be too young to know that one, so feel free to fill it in

"A man with one watch knows what time it is; a man with two watches knows nothing." --> XML has two different systems for specifying schema. And despite the fact that XML is the perfect universal format for storing everything, one of them isn't formatted in XML!

> > Anyway, XML doesn't address data management; it's a document
> > management system.
>
> Sure XML is just a format. But is a format that doesn't play nice with
> SQL-DBMS's (and, yes, I know of everybody and his brothers adapters
> with one end connected to the SQL-DBMS and the other to XML, but some
> folks like me will want that unnecessary component out of there).

Somehow I missed the end of that sentence.

> Somewhere between the SQL-RDBMS and the Semantic Web, exclusive, lies a
> model and implementations thereof that will do a big-bang-for-the-buck
> job and developers will flock to it -- perhaps a hosted database with
> an intuitive interface and constraint-handling that permits end-users
> to add their own new attributes (having just read the other thread on
> that).

Meh, I dunno. Just because something becomes popular doesn't mean it's good, or even the right tool for doing data management. MySQL is about the worst SQL-DBMS for managing data integrity, and it's also the most popular. Maybe its popularity has more to do with the price than with the suckiness. All the good SQL-DBMSs cost big quatloos.

Marshall Received on Wed Jul 20 2005 - 08:21:56 CEST