DAY( )
Returns a number from 1 to 31 representing the day of the month.
Syntax
DAY(date)
Argument
date
The date or date expression from which you want to extract the day.
Returns
The number of the day of the month for the specified date value.
Example
The following example gets the number of the day for each date value in the ShipDate data field:
DAY([ShipDate])