Databases Reference
In-Depth Information
Summary
This chapter explained some of the most common index maintenance operations. You learned how to
collect statistics for indexes. In this connection, it's important to specify correct values for the
METHOD_OPT
parameter and this chapter explained how to do this. Rebuilding indexes is often a
troublesome part of index maintenance due to the many arguments for and against regular index
rebuilds. The chapter discusses both arguments and explains why an automatic rebuild of indexes may
really be unnecessary. The chapter also explains shrinking and coalescing operations and offered
guidelines as to when these operations are appropriate. The chapter explained when Oracle makes an
index unusable and how to deal with it. You also learned how to render an index unusable and when to
do this. Finally, the chapter explained how to use the
DBMS_METADATA
package in order to efficiently
extract the DDL for creating indexes.
