Determining indexes that are not used in 10g

Question

Is there a way to identify indexes that are not utilized in 10g? We have ADDM and AWR running nightly.
Thanks in advance...

Answer 1

You can enable index monitoring with
alter index <index_name> monitoring usage;
When the index is used V$OBJECT_USAGE.USED column will be set to YES. If the index is not used the USED column will show NO.
test@ORCL> alter index i_test monitoring usage;
Index altered.
Elapsed: 00:00:00.04
test@ORCL> select * from v$object_usage;
INDEX_NAME                     TABLE_NAME                     MON USE START_MONITORING    END_MONITORING
I_TEST                         TEST                           YES NO  01/04/2007 07:52:21
Elapsed: 00:00:00.04
test@ORCL> explain plan for
  2  select object_id from test;
Explained.
Elapsed: 00:00:00.10
test@ORCL> select * from v$object_usage;
INDEX_NAME                     TABLE_NAME                     MON USE START_MONITORING    END_MONITORING
I_TEST                         TEST                           YES NO  01/04/2007 07:52:21
Elapsed: 00:00:00.00
test@ORCL> select count(*) from test;
  COUNT(*)
     50425
Elapsed: 00:00:00.00
test@ORCL> select * from v$object_usage;
INDEX_NAME                     TABLE_NAME                     MON USE START_MONITORING    END_MONITORING
I_TEST                         TEST                           YES NO  01/04/2007 07:52:21
Elapsed: 00:00:00.00
test@ORCL> select * from test where object_id =1;
no rows selected
Elapsed: 00:00:00.07
test@ORCL> select * from v$object_usage;
INDEX_NAME                     TABLE_NAME                     MON USE START_MONITORING    END_MONITORING
I_TEST                         TEST                           YES YES 01/04/2007 07:52:21
Elapsed: 00:00:00.00
test@ORCL>You turn of index monitoring with the following:
alter index <index_name> nomonitoring usage;