IOUG: Oracle Indexing Tips Tricks and Trapss

Moscone West L2, Rm 2005
This presentation looks at various tips, tricks, and traps regarding the use and implementation of Oracle indexes. Topics include indexes and constraint management; how different types of indexes are needed for different constraint options; and how constraints, in turn, influence the cost-based optimizer (CBO). Next the session discusses subtle differences between unique and nonunique indexes and why these differences matter. It looks at tricks that make B-tree indexes extremely useful even if columns have few distinct values, as few as just one value. It also looks at how NULLs can actually be indexed effectively in B-tree indexes. Finally, it considers various problems with index monitoring and why the results can't be trusted.