Tuesday, May 02, 2006

Cost-Based Oracle Fundamentals

Been busy the last couple of weeks on the new house.

Even so, managed to get through my first pass of Cost-Based Oracle Fundamentals by Jonathan Lewis. I concentrated more on the concepts the author was trying to get across and less on the math of each operation. On the second go-round, I plan on doing the examples one by one and experimenting with some real-world data.

I didn't count, but I found myself saying "Ah-ha" several hundred times. Histograms, Ah-ha. Cardinality, Ah-ha.

There's a lot of hot air on the internet about Clustering Factor, but there is a whole chapter that sets you straight on the concept; both positives and negatives. The section on how reverse key indexes negatively can affect the Clustering Factor is really eye opening.

I personally got a lot out of Chapter 11, Nested Loops. Nested Loop joins are one of the more common access paths chosen and I thought I had a decent understanding of them. This chapter really filled in the gaps that were missing.

And a whole chapter on the 10053 event? Whoa. I'm sure there's a lot more to it, but now at least I have an idea of what's going on with the optimizer when I look at the trace file.

Lets just say the differences Jonathan points out between 9i and 10g scare me. Big time. A lot of differences are pointed out throughout the book, but there's going to be a ton of testing when 10g comes to town.

Cost-Based Oracle Fundamentals is definitely a recommended read.

No comments: