Examples of the TRUNC function being applied to datetime values : TRUNC « Date Timestamp Functions « Oracle PL/SQL Tutorial

SQL>
SQL> DECLARE
  2     date_in DATE := TO_DATE('24-Feb-2002 05:36:00 PM'
  3                      ,'DD-MON-YYYY HH:MI:SS AM');
  4     trunc_to_year DATE;
  5     trunc_to_month DATE;
  6
  7  BEGIN
  8     trunc_to_year := TRUNC(date_in,'YYYY');
  9     trunc_to_month := TRUNC(date_in,'MM');
 10
 11     DBMS_OUTPUT.PUT_LINE(
 12        TO_CHAR(trunc_to_year, 'DD-MON-YYYY HH:MI:SS AM'));
 13     DBMS_OUTPUT.PUT_LINE(
 14        TO_CHAR(trunc_to_month,'DD-MON-YYYY HH:MI:SS AM'));
 15  END;
 16  /

PL/SQL procedure successfully completed.

SQL>
SQL>
SQL>

13.24.TRUNC
	13.24.1.	TRUNC() parameter list
	13.24.2.	TRUNC(x[, unit]) truncates x.
	13.24.3.	How Oracle Interprets Two-Digit Years
	13.24.4.	Truncates May 25, 2005, to the first day in the month
	13.24.5.	Truncates 7:45:26 P.M. on May 25, 2005 to the hour
	13.24.6.	Examples of the TRUNC function being applied to datetime values
	13.24.7.	TRUNC(date_in,'YYYY')
	13.24.8.	TRUNC(date_in,'MM')
	13.24.9.	TRUNC(): truncate May 25, 2005, to the first day in the year
	13.24.10.	Use TRUNC(date_variable) when you want to extract a date from a timestamp