help me on projecting some tables

Hi, I've to store in a BD some alimentary product, and there are lot of informations like chemical, physical, nutritional characteristics , ... I don't know how to store this info. So I've a lot of product with a lot of corresponding characteristics. I've thought about to create a table where to store all chemical characteristics, a table for nutritional, ecc. and put in the product table the refer ID to all this caracteristic tables. But in this way, there's the problem that now I'm storing 3 chemical charact. but tomorrow I'd like to add a new charact., and I wouldn't change tha table structure adding a new column every time I've a new field that I haven't expected. Can someone show me the right strategy to resolve this kind of problem? Ciao, Carlo ______________________________________________________________________ Abbonati a Yahoo! ADSL con Atlanet! Naviga su Internet ad alta velocità, e senza limiti di tempo! Per saperne di più vai alla pagina http://adsl.yahoo.it