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Hi Tom, please explain the differences between global partitioned index and
local partitioned index.
Thanks!
and we said...
<quote src=expert one on one Oracle>
Partitioning Indexes
Indexes, like tables, may be partitioned. There are two possible methods to
partition indexes. You may either:
Equipartition the index with the table – Also known as a local
index. For every table partition, there will be an index partition that indexes
just that table partition. All of the entries in a given index partition point
to a single table partition and all of the rows in a single table partition are
represented in a single index partition.
Partition the index by range – Also known as a global index. Here
the index is partitioned by range, and a single index partition may point to any
(and all) table partitions.
In the locally partitioned index, the index entries in a given partition, point
into exactly one table partition. The globally partitioned index diagram
however, shows that the index entries in a global index may point into any or
all of the table partitions. Also, note that the number of index partitions may
in fact be different than the number of table partitions.
Since global indexes may be partitioned by range only, you must use local
indexes if you wish to have a hash or composite partitioned index. The local
index will be partitioned using the same scheme as the underlying table.
</quote>
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