Jonathan Lewis eBooks

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 patter...