This is a very odd scenario, so bear with me:
I'm importing data from a CSV file via the Feeds module to create product reference nodes. There are 3 columns that contain a term (let's call the columns "Code Types"), so naturally, I set up 3 vocabularies for the product reference nodes to use and mapped/imported the Code Type's terms into each. The client had determined long ago that the terms would not make much sense to the customers, so being able to search for products by selecting a combination of terms would not be helpful. To combat this, new user-friendly keywords were added on the client's old site by assigning each a combination of the 3 terms. I'm trying to replicate this for the new site, and it's driving me insane.
I first began by adding the same 3 Code Type vocabularies to a new 4th "Product Keywords" vocabulary (Yes, terms within terms). After no luck with term or entity reference fiddling, EVA, etc., I decided referencing would go smoother if I made the Keywords a content type with the 3 Code Type term reference fields instead of its own vocabulary. I'm still open to either option, though.
What has to happen is that a product reference node is automatically assigned the Keyword term that exactly matches its 3 Code Type term reference fields, and not all Code Type term reference fields have to have a value. Here are some examples:
Product #42 has: CodeType1 = "Red" CodeType2 = "Wheel" CodeType3 = "Hot Dog"
Product #216 has: CodeType1 = [empty] CodeType2 = [empty] CodeType3 = "Hot Dog"
Keyword "Sloth" has: CodeType1 = "Red" CodeType2 = "Wheel" CodeType3 = "Hot Dog"
Keyword "Muffin" has: CodeType1 = [empty] CodeType2 = [empty] CodeType3 = "Hot Dog"
Product #42 needs to have the keyword "Sloth" automatically assigned to it.
Product #216 needs to have the keyword "Muffin" automatically assigned to it.
Sorry for the longwindedness. It's urgent, and I'm edging toward panic mode. Any ideas? Please?