User Guide

DateDiff 553

DateDiff

Description

Determines the integer number of units by which date1 is less than date2.

Returns

A number of units, of type datepart.

See also

DateAdd

, DatePart, CreateTimeSpan

History

ColdFusion MX:

• Changed how negative date differences are calculated: this function calculates negative date

differences correctly; its output may be different from that in earlier releases.

• Changed the w and ww masks; they determine the number of full weeks between the two dates.

Parameters

Usage

The DateDiff function determines the number of complete datepart units between the two

dates; for example, if the datepart parameter is "m" and the dates differ by 55 days, the function

returns 1.

Parameter Description

datepart String specifying the units in which to count; for example yyyy requests a date

difference in whole years.

• yyyy: Years

• q: Quarters

• m: Months

• y: Days of year (same as d)

• d: Days

• w: Weekdays (same as ww)

• ww: Weeks

• h: Hours

• n: Minutes

• s: Seconds

date1 Date/time object, in the range 100 AD–9999 AD.

date2 Date/time object, in the range 100 AD–9999 AD.