Creating A Dimension Table From A 3-key Table

Hi All,

I have a situation with a table that was created for a transactional

system with a 3 columns key. The table is similar to the following:

countrystatecitydescription
11221City A from country 1 and state 12
11321City A from country 1 and state 13
21422City B from country 2 and state 14
21522City B from country 2 and state 15


Now I'm trying to create a dts package that would allow me to build a

city dimension table with unique codes (keys) for each city. What kind of

transformation should I use to translate the old codes (based on the

country-state-city key) into the new ones and preserving the data

integrity?

Thanks,

Ignacio