Oracle - Date- Truncate - EXTRACT - To_Char

Truncate a date.


The TRUNC (date) function returns date with the time portion of the day truncated to the unit specified by the format model fmt. The value returned is always of datatype DATE, even if you specify a different datetime datatype for date. If you omit fmt, then date is truncated to the nearest day. Please refer to "ROUND and TRUNC Date Functions" for the permitted format models to use in fmt.



Below will truncate timestamp part from a dateTimeStamp Field

select trunc(dateTimeStamp),count(*) from myTable

SELECT TRUNC(TO_DATE('27-OCT-92','DD-MON-YY'), 'YEAR')
  "New Year" FROM DUAL;
 
New Year
---------
01-JAN-92 

EXTRACT (datetime)

extract_datetime::=

e.g

select extract( month from sysdate) from dual

select extract( year from sysdate) from dual

TO_CHAR

select to_char( sysdate, 'mm' ) from dual ; -- returns 01..12
select to_char( sysdate, 'MON' ) from dual ;-- returns JAN, FEB, ... DEC 
select to_char( sysdate, 'Month' ) from dual ;-- returns January, ... December