If the current date is February 10, 2010, the following queries return 41 because February 10, 2010, is the 41st day since the beginning of the Teradata calendar year:
SELECT TD_SYSFNLIB.DAYNUMBER_OF_YEAR(CURRENT_DATE); SELECT TD_SYSFNLIB.DAYNUMBER_OF_YEAR(DATE '2010-02-10');