| ||||||||||||||||||
![]() Trade In this Item for up to £11.20
Trade in Cost-Based Oracle Fundamentals: v. 1 (Expert's Voice in Oracle) for an Amazon.co.uk gift card of up to £11.20, which you can then spend on millions of items across the site. Plus, get an extra £5 when you trade in books worth £10 or more until June 30, 2012. Trade-in values may vary (terms apply). Find more products eligible for trade-in.
|
Product details
|
The question, "Why isnt Oracle using my index?" must be one of the most popular (or perhaps unpopular) questions ever asked on the Oracle help forums. Youve picked exactly the right columns, youve got them in the ideal order, youve computed statistics, youve checked for null columnsand the optimizer flatly refuses to use your index unless you hint it. What could possibly be going wrong?
If youve 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. Youll 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 Lewisone of the foremost authorities in this fielddescribes the most commonly used parts of the model, what the optimizer does with your statistics, and why things go wrong. With this information, youll be in a position to fix entire problem areas, not just single SQL statements, by adjusting the model or creating more truthful statistics.
Suggested Tags from Similar Products(What's this?)Be the first one to add a relevant tag (keyword that's strongly related to this product)
|
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.
|