why not just store the selected event ID, then use a join query to get the related data rather than storing it multiple times? That's the whole point of using a relational database.
Your friends over here at WebAssist! These Dreamweaver extensions will assist you in building unlimited, custom websites.
These out-of-the-box solutions provide you proven, tested applications that can be up and running now. Build a store, a gallery, or a web-based email solution.