Re: XML newbie

["David Morris" <David.Morris@xxxxxxxxxxxxx>]

Zak,

You don't mention the technology you are using, but I would treat 
your database and XML as persistence objects with different
capabilities. 
XML is good for things that don't get changed by more than one user 
at a time and are not searched extensively. Databases are better for 
transaction oriented data.

With Java, which works pretty well with either a database or XML, you 
would generally convert to objects. If those objects implement common 
support, they can be treated the same in your applications. That way 
you match the best persistence layer with common access techniques. 
Nothing is perfect though and in some cases the overhead of converting

to objects can add too much overhead.

I have used Java classes that implement a NamedValue interface 
successfully to convert between XML/Database. What I found was 
that a file is associated with a name and has rows. Rows have a name 
and have columns, columns have a name and have a single value, etc. 
By looking at whether these items represents Collections you can
traverse 
a database or XML document.

There are Java technologies that help you with this like Hibernate, 
Castor, and JAXB. You might look into them. They provide mechanisms 
for mapping between objects and persistence.

David Morris

>>> Zak_Metz@xxxxxx 5/14/2003 8:51:26 AM >>>
I like trying out "cutting edge" stuff that I can't do at the day job
on
my website. It's a truly never-ending project in which I'm always
trying
to find better ways to do things.
 
At any rate, I think I have a good application for XML, but I can't
seem
to bridge one gap in my understanding. I understand the wonderful
things
I can do once I have my data in XML format, how I can format the page
for the web, for printing, for PDAs, and what-not. I recognize that
all
my data that's now pretty well normalized lends itself to the
hierarchical format of XML. I suspect that if all my data were in XML,
I
would only need to update that one XML document and the stylesheets
would take it from there. What I don't get is how I convert my
existing
data in tables into XML efficiently and keep that XML document
up-to-date. Am I missing the point of XML? I feel like I'm going to
end
up with two copies of my data. I also feel like I'm missing something
obvious. Any help or pointers are appreciated!
 
Zak Metz