average date of birth

Hi, folks.
I have a table with a column Date_of_birth.
I want to evaluate average date_of_birth by grouping on depts.
AVG function doesn't seem to work with datetime col. Plz help.Hi, folks.
I have a table with a column Date_of_birth.
I want to evaluate average date_of_birth by grouping on depts.
AVG function doesn't seem to work with datetime col. Plz help.

r u looking for average of age ??
coz avg of date of birth doesn't make any sense to me.|||yes, i want to evaluate average age on the basis of date of brith stored with in the column|||datediff ?|||AVG(datediff(yy,date_of_birth,getdate()))
this would work, i guess.
thanx|||How's about:

USE Northwind
GO

CREATE TABLE myTable99(Col1 datetime)
GO

INSERT INTO myTable99(Col1)
SELECT '10/24/1960' UNION ALL SELECT '10/24/1970' UNION ALL SELECT '10/24/1980'

SELECT CONVERT(datetime,AVG(CONVERT(float,Col1))) FROM myTable99
GO

DROP TABLE myTable99
GO|||Hi Brett, good morning.
That was what i've been lookin for.
How do we get the date back after it's converted into float.
SELECT convert(datetime,38174.0)
--------
2004-07-08 00:00:00.000
(1 row(s) affected)

Howdy!|||Here is a quick one:

************************************************** ****
SET NOCOUNT ON
/* Here is your table */
create table #working (Date_of_birth datetime)
insert into #working (Date_of_birth) VALUES ('1/1/1920')
insert into #working (Date_of_birth) VALUES ('1/6/1930')
insert into #working (Date_of_birth) VALUES ('1/17/1940')
DECLARE @.days_old int

/* Average days old */
SELECT @.days_old = AVG(datediff(dd, Date_of_birth, GETDATE()))
FROM #working

/* back it out now for average birth date, odd as that is :P */
SELECT dateadd(dd, -@.days_old, GETDATE())

drop table #working
SET NOCOUNT OFF
************************************************** ****

Hope it helps|||Aren't you concerned that cobalt sound a lot like COBOL?