EXTRACT

EXTRACT( YEAR | QUARTER | MONTH | WEEK | DAY | HOUR | MINUTE | SECOND | DOW | DOY FROM <date_or_time_expr> )

SELECT NOW();

now()                |
---------------------+
2023-10-16 02:09:28.0|

SELECT EXTRACT(DAY FROM NOW());

extract(day from now())|
-----------------------+
                     16|

-- October 16, 2023, is a Monday
SELECT EXTRACT(DOW FROM NOW());

extract(dow from now())|
-----------------------+
                      1|

-- October 16, 2023, is the 289th day of the year
SELECT EXTRACT(DOY FROM NOW());

extract(doy from now())|
-----------------------+
                    289|

SELECT EXTRACT(MONTH FROM TO_DATE('2022-05-13'));

extract(month from to_date('2022-05-13'))|
-----------------------------------------+
                                        5|