Actually the only caveat is that you store dates as strings. When you store the dates as datetime you can specify the exact style that should be used in the select statement. For example:

declare @dt datetime

set @dt = getdate()

select convert(char(10),@dt,103) as EurDate, convert(char(10), @dt, 101) as USADate

Since you stored it as nvarchar, you need to use string manipulation functions such as substring, left and right. Here is one way of doing so:

declare @dt nvarchar(6)

set @dt = '022500'

select (left(@dt,2) + '/' + substring(@dt,3,2) + '/' + case when cast(right(@dt,2) as int) >= 70 then '19' else '20' end + right(@dt,2))

Adi