What you want is the same as the DateDiff() function in sql server but Oracle does not have a DateDiff function.
Here is a solution I found for getting days, hours, minutes:
http://asktom.oracle.com/pls/asktom/...42712657900129
I would usually use a DateDiff() that returned months and then divide them by 12 to get the age. Not sure of the best way to do that in Oracle.
As far as the dates being strings you should be able to cast them as dates.
Hope that helps.
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