Rails model to represent multiple fields

I'm developing a rails project where I have one data model with开发者_JAVA技巧 multiple fields that are collection selects. I'd like to create another model to represent all of these collection select fields. So, for instance, my main data model has three collection select fields -- one for county, one for category, and one for classification. I could separate these into three separate data models, but that seems redundant since they all share the same characteristics. They have a type and a value, like a county is a county and it has a value of let's say Sonoma, just as category has a type of category and a value of let's say Winery. If you've ever used Drupal, I'm basically looking for the behavior of the taxonomy functionality.

So you see my dilemma: I need to separate these fields into three separate fields but they have very similar data structures. Any suggestions would be greatly appreciated.

---

This is a perfect case for single-table inheritance. Your problem is screaming for it.