XML in Relational Database

K

Karstens Rage

Sorry if this is a issue that has been discussed before but I am not
even sure how to search for something like this.

Say I have something that is very vague in terms of its definition. Like
maybe a purchase order from a customer. Each customer defines its PO
in terms of an XML schema or DTD which is specific but different for
each customer. Also I don't know ahead of time all the customers' DTD's.

I also have my own specification for how I store customer ID's and dates
and inventory, etc. and I want to put that into a relational database to
allow for all the benefits therein.

So rather than try to force the arbitrary XML into some flexible
database schema, is the standard practice to just store the XML along
with the DB record as a BLOB? What are other options that people/service
use?

In the front end and middle layer, XML is passed around but I eventually
need to store stuff in the backend. I am concerned about having to
constantly modify the database schema in the backend due to unforseen
stuff that I have to account for in the front end. Also I don't want to
have to try and design everything up front to account for anything that
might come along.

Any comments or pointers to discussions that already address this
greatly appreciated.

k
 
J

Joseph Kesselman

Karstens said:
So rather than try to force the arbitrary XML into some flexible
database schema, is the standard practice to just store the XML along
with the DB record as a BLOB? What are other options that people/service
use?

If you can't or don't want to "shred" the XML into tables, your choices
are a LOB with the XML syntax and/or preparsed tree... or to step
outside the relational metaphor and do something based on XML's
structure. IBM has supported the first several options for some time; as
of DB2 they've added an XML-specific data model (the trademark for that
feature is "pureXML") and extended the DB2 metaphors to operate upon it.

https://www.ibm.com/software/data/db2/xml/

Claimer (opposite of a disclaimer): I work for IBM, and I was involved
in some of the early discussion of pureXML's design, so I'm biased
toward it both professionally and personally.
 
J

Joe Kesselman

Joseph said:
structure. IBM has supported the first several options for some time; as
of DB2 they've added an XML-specific data model (the trademark for that
feature is "pureXML") and extended the DB2 metaphors to operate upon it.

Meant to say "As of DB2 version 9. Also known as DB2 9." (And there's a
rumor, which IBM at least hasn't denied, that they seriously considered
declaring that the new XML support was a big enough concept to justify
calling this version DB3.)
 

Ask a Question

Want to reply to this thread or ask your own question?

You'll need to choose a username for the site, which only take a couple of moments. After that, you can post your question and our members will help you out.

Ask a Question

Members online

Forum statistics

Threads
473,744
Messages
2,569,482
Members
44,901
Latest member
Noble71S45

Latest Threads

Top