How to calculate age in T-SQL with years, months, and days

Question

What would be the best way to calculate someone\'s age in years, months, and days in T-SQL (SQL Server 2000)?

The datediff function doesn\'t handle year

Answer 1

Here is a (slightly) simpler version:

CREATE PROCEDURE dbo.CalculateAge 
    @dayOfBirth datetime
AS

DECLARE @today datetime, @thisYearBirthDay datetime
DECLARE @years int, @months int, @days int

SELECT @today = GETDATE()

SELECT @thisYearBirthDay = DATEADD(year, DATEDIFF(year, @dayOfBirth, @today), @dayOfBirth)

SELECT @years = DATEDIFF(year, @dayOfBirth, @today) - (CASE WHEN @thisYearBirthDay > @today THEN 1 ELSE 0 END)

SELECT @months = MONTH(@today - @thisYearBirthDay) - 1

SELECT @days = DAY(@today - @thisYearBirthDay) - 1

SELECT @years, @months, @days
GO