Oracle: SQL select date with timestamp

I have the following data: ``` SQL> select * from booking_session; BK_ID|BK_DATE -----|------------------------- 1|18-MAR-12 10.00.00.000000 2|18-MAR-12 10.25.00.000000 3|18-MAR-12 10.30.00.000000 4|18-MAR-12 10.35.00.000000 5|18-MAR-12 10.40.00.000000 ``` I am trying to write a `sql` query that selects all records that matches a certain date, however I am using timestamp for the `BK_DATE` field and no matter what I try it my query yields no results. SQL: I have tried the following queries but they yield no results 1. ``` select * from booking_session where bk_date = to_date('18-03-2012', 'dd-mm-yyyy'); ``` 2. ``` select * from booking_session where bk_date = to_timestamp('18-03-2012', 'dd-mm-yyyy'); ``` 3. ``` select * from booking_session where bk_date = to_date('18-MAR-2012', 'dd-mm-yyyy'); ``` It only works when I set the whole date value like; ``` select * from booking_session WHERE bk_date = '18-MAR-12 11.00.00.000000'; CREATE TABLE BOOKING_SESSION( BK_ID NUMBER NOT NULL, BK_DATE TIMESTAMP, BK_BOOKER NUMBER, BK_CUSTOMER NUMBER, BK_TREATMENT NUMBER, T_SESSION_DATETIME TIMESTAMP, STAFFAPPOINTED NUMBER, BK_ROOM NUMBER ); INSERT INTO BOOKING_SESSION VALUES ( 1, TO_TIMESTAMP('18/03/2012 10:00', 'DD/MM/YYYY HH24:MI'), 1, 1, 1, TO_TIMESTAMP('20/03/2012 11:00', 'DD/MM/YYYY HH24:MI'),2,1 ); ```