SQL> alter index aa_index01 monitoring usage;
 
Index altered
 
SQL> select * from aa;
 
        ID NAME                 BORN
---------- -------------------- -----------
         1 lishaoqing           2011/10/1
         1 lishaoqing           2011/11/1
         1 lishaoqing           2011/12/1
         1 lishaoqing           2012/1/1
 
SQL> alter index aa_index01 nomonitoring usage;
 
Index altered
 
SQL> select * from v$object_usage where index_name='aa_index01';
 
INDEX_NAME                     TABLE_NAME                     MONITORING USED START_MONITORING    END_MONITORING
------------------------------ ------------------------------ ---------- ---- ------------------- -------------------
 
SQL> select * from v$object_usage where index_name='AA_INDEX01';
 
INDEX_NAME                     TABLE_NAME                     MONITORING USED START_MONITORING    END_MONITORING
------------------------------ ------------------------------ ---------- ---- ------------------- -------------------
AA_INDEX01                     AA                             NO         NO   02/01/2012 09:21:25 02/01/2012 09:21:42
 
如果USED列中放的是YES值，表明該查詢被數據庫使用了，若索引在監控周期中被忽略，則該值為NO.