What Is a Global Partitioned Indexes in Oracle Database?
A global index is partitioned independently of or across table partitions, supporting key access that may span table partitions.
How the Global Partitioned Indexes Algorithm Works
A global index is partitioned independently of or across table partitions, supporting key access that may span table partitions.
When to Use Global Partitioned Indexes
Large partitioned tables needing global key lookup or partitioned index segments.
How to Create a Oracle Database Global Partitioned Indexes
Review data quality, existing structures, feature support, build time, and deployment requirements before creating an index on a production table.
CREATE INDEX orders_customer_global_ix ON orders (customer_id) GLOBAL PARTITION BY HASH (customer_id) PARTITIONS 8;Global Partitioned Indexes Query Example
This example demonstrates the matching query shape. Check the execution plan to confirm that the engine can use the index.
SELECT order_id FROM orders WHERE customer_id = :customer_id;Queries Supported by Global Partitioned Indexes
Large partitioned tables needing global key lookup or partitioned index segments. A similar-looking predicate may not use the same access path; operators, expressions, key order, and data type all matter.
Read Performance, Storage, and Write Costs
Partition maintenance may invalidate or require maintenance of global indexes; operations are more complex. Indexes reduce some search work but require storage and add maintenance to writes.
Global Partitioned Indexes Limitations and Common Mistakes
Table partition DDL and global index usability must be coordinated.
Do not assume that an index being present means the optimizer chose it or that the query became selective.
How to Measure and Tune Global Partitioned Indexes
Monitor index status after partition operations and plan rebuild/update procedures.
Compare representative plans and timings before and after, including concurrent writes and realistic data volumes.
Global Partitioned Indexes Questions
Will the database always use this index?
No. The optimizer weighs selectivity, estimated costs, statistics, cache state, and the amount of data returned.
What should I verify before production?
Confirm version support, query compatibility, write overhead, build/rollback procedures, and index behavior during backup and recovery.
Official Oracle Database Index Documentation
Check Oracle Database Concepts: Indexes and Index-Organized Tables for release-specific requirements and supported operators.