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Partitioned Tuning   «Prev 

Oracle Local Index

To maximize the benefits of partitioning, it sometimes makes sense to partition a table and an index identically so that both
  1. the table partition and
  2. the index partition
map to the same set of rows. You can automatically implement this type of partitioning, which is called equipartitioning[1], by specifying an index for a partitioned table as a LOCAL index. Local indexes simplify maintenance, since standard operations, such as dropping a partition, will work transparently with both the index partition and the table partition.
The ability to partition tables and indexes has had a dramatic impact on the use of Oracle for data warehousing applications. Object partitioning means that Oracle can handle 1000 terabytes of data.

A master index node makes the separate indexes appear as a single index.

Each local partition has a separate index tree.

[1] equipartitioning: If you partition a table that has a nested table, then Oracle Database uses the partitioning scheme of the original base table as the basis for how the nested table is partitioned. This partitioning of one base table partition for each nested table partition is called equipartitioning. By default, nested tables are automatically partitioned when the base table is partitioned. Note, however, that composite partitioning is not supported for nested tables.