Best way to extract XML data to DB

Question

Hello,
In our work we need to extract data from XML documents into a database. Here are some extra notes:
+ There is no constant schema for the XML documents.
+ Some processing on the XML files is required.
+ The XML documents are very big.
+ The database is Oracle 8i or 9i (Enterprise Edition both) and our framework is NET.
Our questions are:
1. What is the best way to extract the data into the database under the above circumstances ?
2. In case there was a constant schema for the XML documents, would there be a better way ?
3. Is writing the data to text files first, and then loading it via SQL-Loader is an effective way ?
Any thoughts would be welcome. Thanks.

Answer 1

Hi Nicolas,
The answer depends on your actual storage method (binary, OR, CLOB?), and db version.
You can try XMLTable, it might be better in this case :
SELECT x.elem1, x.elem2, ... , x.elem20
FROM your_table t
   , XMLTable(
      '/an/xpath/to/extract'
      passing t.myxmltype
      columns elem1  varchar2(30) path 'elem1'
            , elem2  varchar2(30) path 'elem2'
            , elem20 varchar2(30) path 'elem20'
     ) x
;