I have one class and some characteristic:
Characteristic Region: values (America, Africa and Europe)
Characteristic Country: values Germany, South Africa, Mexico, USA and Italy
Characteristic Cities: values Veneza, Guadalajara, New York and Frankfurt.
My idea is:
When I select America in characteristic Region, in characteristic Country only Mexico and USA is available and characteristic Cities only Guadalajara and New York.
What's the best solution?