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:
You can download the free DB2 Express-C from the same page.
For training roadmaps, DB2 9 database associate certification, and links to details of courses, free tutorials and books, see:
Rates of pay
DB2 database administrators with two years' experience can earn between £30,000 and £45,000 a year.
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