To be crystal clear, would you ever have data like the following where a given single product appeared in the CSV of more than 1 product category? I ask because this WILL cause a partial Cartesian Product and THAT will determine the "best" way to handle the tables as they currently exist.

1 canola,tea,muffin,cheese jellyproducts null

2 vinegar,canola,sunflower oliproducts null

3 cornil,vegoil,canola,sesameoil oilproducts null

4 margarine,butter,muffin,bagel butterproducts null

5 muffin,bagel,wheatbread breadproducts null

6 tea,coffee,hotcocoa hotdrinkproducts null