I've got a database which consists of 2 fields known as DateOfBirth and Age, for storing customers DOB and age correspondingly. I would like the Age column to become instantly incremented by 1 each year, based on the DOB matching server date.

What is the easiest way for accomplishing this? I'm using asp.internet and sql server 2008.

Instead of store both DateOfBirth and Age, produce a computed column up for grabs that computes age:

[Age] AS datediff(year,  DateOfBirth, getdate()) 

So in yout table creation:

-- Create Table with computed column
CREATE TABLE [dbo].[CCtest]
(
    [id] [int] not NULL,
    [DateOfBirth] [datetime] NULL,
    -- etc...
    [Age] AS datediff(year,  DateOfBirth, getdate()) 
)
GO 

If you wish to persist the calculated value add the PERSISTED keyword.

One possibility, if you would like Age displayed in a long time and several weeks:

    [AgeInDays] AS datediff(day,  DateOfBirth, getdate()) 

then produce a view over your table that formats AgeInDays into many several weeks.

Here's another possibility, utilizing a calculated column of [AgeYears]:

create view vwCCtestAge
AS
select 
   id, 
   dateofbirth,
   cast([AgeYears] as varchar(4)) + ' years ' + 
      cast(datediff(month, DateOfBirth, getdate()) 
           - case when (AgeYears > 0) then (AgeYears - 1)*12 
                  else 0 
             end as varchar(4)) + ' months' as Age
   from cctest2
   GO

[You can examine for boundary cases...]