Insert XML file into Relational database model without using XMLTYPE tables

Question

Dear all,
How can I store a known complex XML file into an existing relational database WITHOUT using xmltypes in the database ?
I read the article on DBMS_XMLSTORE. DBMS_XMLSTORE indeed partially bridges the gap between XML and RDBMS to a certain extent, namely for simply structured XML (canonical structure) and simple tables.
However, when the XML structure will become arbitrary and rapidly evolving, surely there must be a way to map XML to a relational model more flexibly.
We work in a java/Oracle10 environment that receives very large XML documents from an independent data management source. These files comply with an XML schema. That is all we know. Still, all these data must be inserted/updated daily in an existing relational model. Quite an assignment isn't it ?
The database does and will not contain XMLTYPES, only plain RDBMS tables.
Are you aware of a framework/product or tool to do what DBMS_XMLSTORE does but with any format of XML file ? If not, I am doomed.
Constraints : Input via XML files defined by third party
Storage : relational database model with hundreds of tables and thousands of existing queries that can not be touched. The model must not be altered.
Target : get this XML into the database on a daily basis via an automated process.
Cheers.
Luc.

Answer 1

Luc,
your Doomed !
If you would try something like DBMS_XMLSTORE, you probably would be into serious performance problems in your case, very fast, and it would be very difficult to manage.
If you would use a little bit of XMLType stuff, you would be able to shred the data into the relational model very fast and controlable. Take it from me, I am one of those old geezers like Mr. Tom Kyte way beyond 40 years (still joking). No seriously. I started out as a classical PL/SQL, Forms Guy that switched after two years to become a "DBA 1.0" and Mr Codd and Mr Date were for years my biggest hero's. I have the utmost respect for Mr. Tom Kyte for all his efforts for bringing the concepts manual into the development world. Just to name some off the names that influenced me. But you will have to work with UNSTRUCTURED data (as Mr Date would call it). 80% of the data out there exists off it. Stuff like XMLTABLE and XML VIEWs bridge the gap between that unstructured world and the relational world. It is very doable to drag and drop an XML file into the XMLDB database into a XMLtype table and or for instance via FTP. From that point on it is in the database. From there you could move into relational tables via XMLTABLE methods or XML Views.
You could see the described method as a filtering option so XML can be transformed into relational data. If you don't want any XML in your current database, then create an small Oracle database with XML DB installed (if doable 11.1.0.7 regarding the best performance --> all the new fast optimizer stuff etc). Use that database as a staging area that does all the XML shredding for you into relational components and ship the end result via database links and or materialized views or other probably known methodes into your relational database that isn't allowed to have XMLType.
This way you would keep your realtional Oracle database clean and have the Oracle XML DB staging database do all the filtering and shredding into relational components.
Throwing the XML DB option out off the window beforehand would be like replacing your Mercedes with a bicycle. With both you will be able to travel the distance from Paris to Rome, but it will take you a hell of lot longer.
:-)