Separating a date column in Access into Month, Day and Year while keeping the new columns ordered by a seperate column(primary key)
Select FileNumber, 
    DateOpen as DayOpen, 
    Month(#DateOpen#) as MonthOpen, 
    Year(#DateOpen#) as YearOpen
From [file]
Order by FileNumber


I assume by day you just want to show the date you have from the day open field. Month(DateOpen) will give you the month number.  You weren't specific about what you were looking for in this field, so I assume this is ok. Order By FileNumber ensures you maintain the order of the primary key field.