A lot of posts are now out there, with peoples top 10 lists, regarding Oracle…
Category: XMLDB
The following is an extension on the former post about “About Table(XMLSequence()) and XMLTable”. These examples where based on a XMLType column using CLOB storage. If you have read the “Oracle 11g – XMLType Storage Options“, then you should now know that this storage model is only performing if you had a document centric environment in mind.
Oracle’s 11g addition “XMLIndex”, will give you an solution for these kinds of environments.
The XMLIndex is a domain index, specially crafted for use in a XMLDB environment. It is a logical index with 3 components (excerpt Oracle 11g beta XMLDB Developers Guide):
A customer asked me how this XMLTable XML function works… Until now they had to use the TABLE(XMLSEQUENCE()) constructor.
While testing performance differences between a RedHat AS V3 (Oracle Enterprise Version 10.1.0.3, RAID 1+0) machine and a full blown LPAR IBM AIX 64b 5.3 environment (Oracle Enterprise Version 10.2.0.2) with EMC (RAID 5) they wanted to use the XMLTABLE XML function.
Why? Oracle promotes the use of the XMLTable function on 10.2.x and higher Oracle versions. My belief is that the TABLE(XMLSEQUENCE()) constructor will be deprecated in favor of the XMLTABLE function. Also the XMLTABLE function supports XQuery functionality.
They had a simple statement to test with.