I have two Oracle columns (in a VIEW, not a table) - DateOfBirth and MembershipDate. I am trying to create a new column that will show the age of the person on the date that they took up the membership.

**Sample columns:**  
**DateOfBirth:** 01/05/1975  
**MembershipDate:** 01/09/2015  
**AgeWhenBecameMemb:** 40

How do I get the third column to get calculated on the fly, please?

I'm looking to implement it using something like this:

> 
> SELECT FLOOR(MONTHS\_BETWEEN(DATE '2012-01-01', DATE '2010-10-10')/12) AS AgeWhenBecameMemb from DUAL
> 
> 
> 

Thanks!