YEAR(t), MONTH(t), and DAY(t) are functions (extraction) that extract the year, month, and day from the specified date or time stamp value.

Value t: When used in a function, the expression t must supply a date, a time stamp, or an alphanumeric value that matches the current date or time stamp format.

Result of the Function

YEAR(t), MONTH(t), DAY(t)

Numeric value (year, month, day)

t is a NULL value

NULL value