Seamlessly manage relational and XML data
types
What is it?
Sales and revenues may fluctuate, but IBM DB2 databases hold
more structured data than any rival product and boast some of the
world's biggest installations.
IBM remains supreme on the mainframe, despite challenges from
Oracle for Linux on zSeries, and competitors such as Computer
Associates, Cincom and Software AG. For smaller implementations,
the main challenger is Microsoft's SQL Server, but IBM covers the
full range of platforms likely to be in use - Windows, Unix and
Linux, and its own midrange systems.
DB2 9, previously known as Viper, was launched this summer with
versions for large businesses and small and medium-sized
enterprises. DB2 9 represents a technology breakthrough, seamlessly
integrating relational and XML data.
Where did it originate?
DB2 appeared on the mainframe in 1982, but its origins date back
to work done by IBM's Ted Codd on relational databases. Throughout
the 1990s, IBM steadily ported DB2 to other platforms, and
integrated DB2 into its own midrange systems - it is embedded in
the i5/OS operating system for the iSeries, for example. Following
Informix's lead, IBM made DB2 object-relational and added
"Universal Database" (UDB) to the name - and subsequently bought
Informix, adding its technology to DB2 UDB.
What's it for?
DB2's big claim is that it can manage "all" types of data,
including documents, audio and video files, images, web pages, and
digitally signed XML transactions. Alongside the "pure XML"
technology, the major advances are Venom storage compression and
enhanced autonomic data management capabilities.
According to IBM, Venom brings mainframe-style compression
techniques to the full range of DB2 platforms, reducing disc, I/O
and memory overheads. Autonomic data management takes a lot of the
manual work out of database administration, which may have
implications for the amount of database administrator work
available, as will the "seamless" relational and XML management
made possible by pure XML.
Developers can use either the XML standards XQuery and XPath to
retrieve data from relational and XML storage, or traditional SQL,
or a combination of the three. Like all IBM's mainstream products,
DB2 supports Java 2 Enterprise Edition. There is a DB2 Developer's
Workbench, but also support for .net, and applications can be built
using Microsoft's Visual Studio.
What makes it special?
According to Philip Howard, director of research at Bloor
Research, pure XML will have a direct impact on performance.
"Performance comparisons by early adopters of Viper indicate gains
on queries of 100 times or more, development benefits of between
four and 16 times, the ability to add fields to a schema in a
matter of minutes as opposed to days," he said.
How difficult is it to master?
Certification as a DB2 database associate involves three courses
of two days each, although IBM offers free tutorials as an
alternative to some courses. The most advanced certification as
developer or architect would take 20 days in the classroom, and a
daunting amount of reading over a number of years.
What systems does it run on?
z/OS, AIX, HP-UX, Sun Solaris, Linux and Windows.
What's coming up?
DB2 9 will ship from the end of July. In the meantime, you can
download DB2 "images" from:
www-306.ibm.com/software/data/db2/udb/db2express/download.html
You can download the free DB2 Express-C from the same page.
Training
For training roadmaps, DB2 9 database associate certification,
and links to details of courses, free tutorials and books, see:
www-306.ibm.com/software/data/education
www-128.ibm.com/developerworks/db2
Rates of pay
DB2 database administrators with two years' experience can earn
between £30,000 and £45,000 a year.
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