Creates a date from the numbers for year, month, date and optionally hour, minute and second.
If the parameter is a number, then it creates a datetime since 12/31/1899 12:00:00.
If the parameter is a string, then it parse the string to create a datetime. An error will occur, if it can not interpret the string as a date. A valid string is: "September 23, 2004". For more information, see the list of supported date/time formats.

DateTime( Date, Time )
DateTime( number )
DateTime( string )
DateTime( YY, MM, DD)
DateTime( YY, MM, DD, HH, mm, SS )

Date object

DateTime(2002,11,26)
-> Returns the date time value: 11/26/2002 00:00:00.

DateTime(2002,11,26,17,30,0)
-> Returns the date time value: 11/26/2002 17:30:00.

DateTime(25569 + {table.column} / 86400.0 )
-> Returns the date time, created from the seconds since 1/1/1970.

DateTime( "September 23, 2004" )
-> Returns the date time value: 9/23/04  12:00:00 AM CEST.