How to see how many times of index split occured on an index?

Question

hi gurus
The ASH reports shows a lot of enq: index contention wait event on an index.I suspect that it's index split that caused the waits. From wht dictionary can I see the times of index split once occured on that index?
Thanks very much!

Answer 1

http://download.oracle.com/docs/cd/B19306_01/server.102/b14211/instance_tune.htm#i16341
The name of the enqueue is included as part of the wait event name, in the form enq: enqueue_type -  related_details. In some cases, the same enqueue type can be held for different purposes, such as the following related TX types:
    *      enq: TX - allocate ITL entry
    *      enq: TX - contention
    *      enq: TX - index contention
    *      enq: TX - row lock contention
The V$EVENT_NAME view provides a complete list of all the enq: wait events.
You can check the following V$SESSION_WAIT parameter columns for additional information:
    *      P1 - Lock TYPE (or name) and MODE
    *      P2 - Resource identifier ID1 for the lock
    *      P3 - Resource identifier ID2 for the lockdoes following SQL return any rows for you?
SELECT Decode(request, 0, 'Holder: ',
                       'Waiter: ')
       || sid sess,
       id1,
       id2,
       lmode,
       request,
       TYPE
FROM   v$lock
WHERE  ( id1, id2, TYPE ) IN (SELECT id1,
                                     id2,
                                     TYPE
                              FROM   v$lock
                              WHERE  request > 0)
ORDER  BY id1,           request;