Date

A date is a three-part value (year, month, and day) designating a point in time under the Gregorian calendar, which is assumed to have been in effect from the year 1 A.D.

The range of the year part is 0001 to 9999.¹ The date formats *JUL, *MDY, *DMY, and *YMD can only represent dates in the range 1940 through 2039. The range of the month part is 1 to 12. The range of the day part is 1 to x, where x is 28, 29, 30, or 31, depending on the month and year.

The internal representation of a date is a string of 4 bytes that contains an integer. The integer (called the Scaliger number) represents the date.

The length of a DATE column as described in the SQLDA is 6, 8, or 10 bytes, depending on which format is used. These are the appropriate lengths for string representations for the value.

¹ Note that historical dates do not always follow the Gregorian calendar. Dates between 1582-10-04 and 1582-10-15 are accepted as valid dates although they never existed in the Gregorian calendar.