Product Description

The question, "Why isn't Oracle using my index?" must be one of the most popular (or perhaps unpopular) questions ever asked on the Oracle help forums. You've picked exactly the right columns, you've got them in the ideal order, you've computed statistics, you've checked for null columns--and the optimizer flatly refuses to use your index unless you hint it. What could possibly be going wrong? If you've suffered the frustration of watching the optimizer do something completely bizarre when the best execution plan is totally obvious, or spent hours or days trying to make the optimizer do what you want it to do, then this is the book you need. You'll come to know how the optimizer "thinks," understand why it makes mistakes, and recognize the data patterns that make it go awry. With this information at your fingertips, you will save an enormous amount of time on designing and trouble-shooting your SQL. The cost-based optimizer is simply a piece of code that contains a model of how Oracle databases work. By applying this model to the statistics about your data, the optimizer tries to efficiently convert your query into an executable plan. Unfortunately, the model can't be perfect, your statistics can't be perfect, and the resulting execution plan may be far from perfect. In Cost-Based Oracle Fundamentals, the first book in a series of three, Jonathan Lewis--one of the foremost authorities in this field--describes the most commonly used parts of the model, what the optimizer does with your statistics, and why things go wrong. With this information, you'll be in a position to fix entire problem areas, not just single SQL statements, by adjusting the model or creating more truthful statistics.

Product Details

• Amazon Sales Rank: #26187 in Books
• Published on: 2005-10-01
• Original language: English
• Number of items: 1
• Binding: Paperback
• 536 pages

Customer Reviews

This book is exceptional
It's my favourite Oracle book of the many I've read and I'm not expecting it to be surpassed any time soon.

This book takes takes a complex and essential component of the Oracle architecture, the Cost Based Optimiser, and teaches it from the basics up to the complex using an elegant tutorial style. Jonathan doesn't stint on the deep detail that's necessary to understand the subject but he doesn't baffle you with science either. You might need to read it a little more slowly and carefully than you would some third-party Oracle books and play around with the plentiful small examples (which are all available online) but that's because you're getting enough information to justify the purchase cost (and much more) and you know when you get to the end that you'll understand the subject *properly*. With that understanding, it'll be much easier to work out why the CBO is doing something that you've never seen it do before. As always with technical subjects, everything springs from the fundamentals.

No matter what your involvement with Oracle is, you can not avoid the optimiser. I bet you there'll be plenty of people in Oracle Support with this book on their desk!

If you think you're a serious Oracle professional, you should
own this book, devour the contents and experience plenty of those moments when the lights go on and you think - 'Oh, right, so *that's* why it does that'. That includes DBAs who'll learn something new about how their decisions on free lists, block sizes and so on can affect application performance. I can't imagine that there is anyone out there who won't learn something new from this book and you'll finally be able to take a *structured approach* to solving CBO problems instead of just guessing.

I think this book is an absolute classic among books about Oracle and that it’s the only book you'll ever need to truly understand the cost based optimiser (apart perhaps for Volumes Two and Three that will cover more specialised subjects).

Buy it - you won't be disappointed.

deep and detailed, yet surprisingly easy to follow
Outstanding and excellent book - and I'm saying this after six months of reading and re-reading, and running and studying the provided scripts, and even performing my own investigations starting from the book's test cases.

It has been surprisingly easy to understand the material, even if I didn't know most of the things discussed. Reading has flown seamlessly, not exactly like reading a novel, but close enough for a technical book about the very complex CBO - and that was something I didn't expect at all, a very very nice surprise.

The most fundamental topics (the first ones are selectivity, cardinality, etc) being right at the beginning, I didn't need to read the whole book to start using the new knowledge effectively in practice, thus getting the "morale boost" that motivated me to read the next chapter, and then the next ... adding layer after layer of knowledge.

I also *loved* the high level of detail, which is absolutely necessary to understand the complex CBO, and the precise and succinct writing style as well, which makes for an easier and quicker learning. When speaking about mathematical subjects (since the CBO is just that of course - a mathematical model), it's mandatory to be precise and detailed: vague statements would only add confusion or, worstly, misunderstanding.

To recap - I've got home a vastly improved understanding of the CBO - and for a fraction of the effort I thought it would have taken.

Cost–Based Oracle Fundamentals – Jonathan Lewis
As a DBA I was really looking forward to reading this book and I wasn't disappointed. It is perhaps, a little hard-going in places, but this is not at all surprising as the subject it covers is complex.
I thought the book was well structured and very well written. Each chapter contained lots of detailed information, plenty of interesting examples and a list of downloadable scripts to illustrate the text.
All in all, I thought this was an excellent book and a very useful and comprehensive reference. It comes highly recommended and definitely deserves a place on my Oracle bookshelf.