Beginning Oracle Database 11g Administration From Novice to Professional

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CHAPTER 7 PHYSICAL DATABASE DESIGN
to each storage pool using some criterion. The partitioning methods provided by
Oracle include list partitioning, range partitioning, interval partitioning, reference
partitioning, hash partitioning, and composite partitioning.
in the same way as its table. Local indexes are most suitable when the query specifies
the partitioning criterion; they also promote partition independence. Global
indexes are most suitable when the query does not specify the partitioning criterion.
A global index may or may not be partitioned and can even have a different
partition scheme than its table.
Denormalized tables and materialized views can be used to improve the efficiency
of Join operations. Oracle automatically modifies the data in a materialized view
whenever the data in the underlying tables is modified. The optimizer silently
rewrites queries and incorporates materialized views if possible. Materialized views
can also be used to aggregate information or to synchronize satellite databases.
Hash clusters provide quick access without the need for an index (if the value of
the clustering key is specified in the SQL query). They improve the efficiency of the
memory cache (and consequently of Join operations) because data from related
tables can be stored in the same data blocks.
Exercises
Oracle Database 11g Java Developer’s Guide. Construct SQL language commands
to create a suitable set of indexes on the , , , and
tables.
clause of the or
commands to track whether your indexes are being used by the query optimizer.
Where is the information stored? Is it advisable to monitor usage continuously? How
would you stop monitoring index usage?
SQL Access Advisor in the example in this chapter?
Do indexes provide any advantage if the tables are very small?
Organized Tables not invalidated if a DML operation causes rows to move?