XML database engines (Was: Announce: XML::EP)

["Wiedmann, Jochen" <jo...@softwareag.com>]

> XML databases are in my view pointless.  We can use any  number of tools
> to generate XML from database records.  Using text files to store database
> information is slow at best, and unusable at worst.

That's like arguing against the use of XML in favour of CSV files.
An XML database engine can do anything that an SQL engine can do -
and even more. Consider a database with customers and order.

The customer-order relation is obviously better normalized, so you
implement it with a customer table and an order table. So you do
in an XML engine: You create a document type customer and a
document type order. However, did you consider the order positions?
You need a third table in the case of the relational database.
Big deal, you say. I use joins and everythigs fine.

But, beleave me as someone who is used to the subject: It is just
simpler in the application to view the XML document than the two
tables (order/orderpos). You never want to use the former without
the latter and vice versa. Normalization is ugly in that example.

Again, this is not the case for customer/order: You *are* using
the customer as a separate thing and you *are* using the order as
a separate thing.

Sorry for speeking as an employee of a company selling an XML database,
I'll stay quiet on the subject from now on. However, I am also someone
who knows both worlds and I doubt most others have.


Thanks,

Jochen