indexing - Oracle:How to check index status? -

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i create index createdate_idx on field createdate, make query:

select * tablename createdate>=to_date('2016-02-29','yyyy-mm-dd');

but not sure whether index createdate_idx has been used or not. how can make confirm?

explain plan show index used , other information.

for example:

explain plan select * tablename createdate>=to_date('2016-02-29','yyyy-mm-dd');  select * table(dbms_xplan.display);  plan hash value: 3955337982  ------------------------------------------------------------------------------- | id  | operation         | name      | rows  | bytes | cost (%cpu)| time     | ------------------------------------------------------------------------------- |   0 | select statement  |           |     1 |     9 |     2   (0)| 00:00:01 | |*  1 |  table access full| tablename |     1 |     9 |     2   (0)| 00:00:01 | -------------------------------------------------------------------------------  predicate information (identified operation id): ---------------------------------------------------     1 - filter("createdate">=to_date(' 2016-02-29 00:00:00',                'syyyy-mm-dd hh24:mi:ss'))  note -----    - dynamic statistics used: dynamic sampling (level=2)

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