Wednesday, May 06, 2009

Sojourn through the Concepts Guide: 1 of 27

I have been challenged on at least three occasions to read the Concepts guide (thanks to Tom Kyte, Rich Niemiec and Job Miller).

The Concepts Guide (Book? Epic Saga?) is quite large. 542 pages at 8.07mb (PDF version), compacting the knowledge about the Oracle RDBMS into a mere 27 chapters. Since I am most familiar with 10g, I decided to start there. I noticed that the Primary Author (Michele Cyran) is also noted as Primary for the 9i version, and I imagine that she is listed as a Contributing Author in the 11g version merely because so much of the content is reused (which makes sense - hard to improve upon a such a good thing). After reading the first few pages of each, I confirmed that much of the original content is unchanged. Again, this makes sense - we are talking about concepts, and the basic, fundamental concepts of the RDBMS have not changed that much, if at all (aside from new features).

The first chapter, as an overview, is excellent! I found myself being surprised that it was possible to sum up the entire thing in just 38 pages without obviously cutting out too much. Given that, I was equally surprised that there is so much attention given to the Grid Architecture (one blatant, rather large addition since the 9i version).

So, going through the first chapter chronologically.
I found the opening statements quite appropriate - again, an excellent summary. How often have DBAs been asked by lay folks and family members "What is a database?". I like how the author starts at ground zero and builds upwards.

The next 7 pages spent a bit of time on the Grid Architecture. Surprising, as it spans not only the roadmap of the database but extends to Applications and even to the enterprise as well (from Storage to how Information is handled as a commodity). While I agree with the theory of these ideas, and I see how it would be easy to get caught up in the novelty, from practical experience I know these features are whitewashed pretty well for general consumption as the PR folks try to sell it. But I digress. The bottomline is that I value the insight we are provided by these pages, as it gives those of us outside the Oracle Corp a general idea where Larry is going.

The "How Oracle Works" section on 1-17 is excellent as well. This is the kind of stuff that makes me want to go and read about all the nitty-gritty details. The flow and overly-simplisitic nature of this section is perfect in this part of the Guide.

Another interesting point was the short blurb on Quiesce (1-20). I have never thought to use Quiesce to put the database into a sort of "restricted mode". In fact, the few occasions in the past that I have found my database in Quiesced mode, SYS could not do anything (other than shutdown/startup and change the mode back). Shows how little I know about this feature.

The rest of the chapter was appropriately basic, in my opinion. Lots of good bits of information, and I think they set the stage well for the rest of the Guide.


Charles Schultz said...

Oh, another thought on this. My purpose in posting is mostly for myself, as a means of having notes I can refer back to. =) My notes are not intended to be complete nor comprehensive in any way. But I do welcome any other thoughts for those who tread these paths.

yas said...

Concepts Guide rocks!