Oracle PL/SQL Tutorial/Date Timestamp Functions/TO TIMESTAMP
TO_TIMESTAMP(x, format) convert the string x ( CHAR , VARCHAR2 , NCHAR , or NVARCHAR2 ) to a TIMESTAMP.
SQL>
SQL> SELECT TO_TIMESTAMP("2005-05-13 07:15:31.1234", "YYYY-MM-DD HH24:MI:SS.FF")
2 FROM dual;
TO_TIMESTAMP("2005-05-1307:15:31.1234","YYYY-MM-DDHH24:MI:SS.FF")
---------------------------------------------------------------------------
13-MAY-05 07.15.31.123400000 AM
SQL>