How to Monitor Index Usage?

How to Monitor Index Usage?

To start monitoring an index run following statement:

The "V$OBJECT_USAGE" view only retrieves information about object usage of the current connected user/schema.

 Sqlplus> alter index 'index_name' monitoring usage;

To monitor index usage query V$OBJECT_USAGE 

 Sqlplus> Select index_name,monitoring,used,start_monitoring,
                  end_monitoring from v$object_usage;

If an index was used since monitoring started, columns 'MONITORING' and 'USED'  
will show a value of 'YES'

View Definition:
    Use the following SQL to see the view definition of the related GV$ view:

      SELECT view_definition FROM v$fixed_view_definition
       WHERE view_name='GV$OBJECT_USAGE';

NOTE:136642.1 - Identifying Unused Indexes with the ALTER INDEX MONITORING USAGE Command
NOTE:144070.1 - Identifying Unused Indexes
NOTE:203645.1 - How to Monitor Index Usage?