Thanks to write such great example.

Anyway I don’t find any other [xml] database can perform such task except DB2. XQuery+SQL+TEXT INDEX+Stored Proc.

I think I will explore your blog deeper.

data centric-traditional databases like Mysql ,oracle etc etc?
document centric-XML besides db2 or oracle?

re Q1): Note that XML itself is not a database. XML is just a data format. Where do you store the XML? Storing the XML in a database like DB2 gives you significant benefits over storing XML in the file system, such as full support for XQuery and SQL/XML to query the XML, XML indexing for performance, XQuery Update Facility, efficient XML Schema validation, full logging and recoverability, and options for replication, high availability, data partitioning and clustering, and so on. Many of the same reason why you store relational data in a database and not in a text file.

re Q2) On example where storage data as XML is faster than normalized relational storage is when you are dealing with complex business records, such as financial trades, patient records, tax returns, and so. Storing them in a normalized relational database schema often requires dozens if not hundreds of tables. This implies that a business record needs to broken into many pieces that need to be inserted across the tables, and later these pieces need to be retrieved to reassemble the original business record. This can be complicated and slow. If each business record is represented as a single XML document, then insert and retrieval can often be much faster.

In this context you may also find the following article interesting:
http://www.ibm.com/developerworks/data/library/techarticle/dm-1201normalizationpart2/index.html

Matthias

Q2)I have been asked many times: “What is faster, XML or Relational?”. Of course, this question oversimplifies a complex issue, and so the only valid answer is “It depends!” as said by you.Could you gimme an example for this i mean for the small data is XML faster?

Do you mind that i’m asking you questions many times?
because i don’t have assistance or help from any1.