Indexing, IT Opinion, Streams

Indexing

Two more great performance related postings from Richard Foote, the indexing guru:

The Cardinality of leading columns


and

Index Create and Rebuild Locking Improvements in 11g

IT Opinion: Data Modeling

Andrew Clarke over at the Radio Free Tooting blog opines at some length about data modeling, is it a dying art (if not a dead one)? I have to admit that I did a lot more data modeling in the course of my career taking courses about data modeling than I did in the actual work. Perhaps it is partly a result of the increasing specialization of our field. Many DBAs do nothing but maintain systems that have been handed to them, all design work completed (albeit sometimes with tragicomic results). The number of instances is also a sobering fact of life. In the past it would be unusual to find a DBA responsible for more than five instances. Now a mere five instances managed would be rare indeed in a large enterprise environment. With the availability of advanced monitoring and control system there are many DBA managing dozens of instances without breaking a sweat (ok, ok, without breaking a sweat often).

In the realm of speculation I would add that I see a future where DBA work is translated more and more into intelligent agents (no, not those, REALLY intelligent agents). Small, artificial intelligence program will be able to take a lot of the drudgery out of the tasks involved, calling in humans over a grid of responsibilities distributed through Workflow as needed. When the program detects that it is in a fuzzy area it will call in a human to make a sensible decision.

This kind of approach is not far in the future. There are already interesting experiments using the so-called mechanical Turk approach. This divides tasks into numerous mini-tasks that are shared among a group of volunteer or low-paid humans over the Net. They accomplish tasks, such as sophisticated pattern recognition, where the technology still lags behind our brain's abilities, and a computer handles reassembling the tiny tasks into a consistent result.

Streams

There's an outstanding article for those using or studying Oracle Streams at Chen Shapira's I'm Just a Simple DBA blog here. Streams sometimes seems a rather arcane subject, but can be an absolutely revolutionary feature of the Oracle RDBMS when used wisely.