Returns a numerical value, indicating the day of the week corresponding to the specified DateTime value, where 0 = Sunday, 1 = Monday, 2 = Tuesday, 3 = Wednesday, 4 = Thursday, 5 = Friday and 6 = Saturday.
The integer portion of the DateTime value specifies the number of days since January 1stDecember 30th, 19001899, and the fractional portion of the DateTime value specifies the fraction of the day since midnight.
== Usage ==