title: Class diagram conversion to relational model; Inheritance, and a table for matching
body: <p>For a school project, I'm supposed to design the systems of a previous semester's project. We're using UML, creating an extremely simple use case diagram (no <code>&lt;&lt;extend&gt;&gt;</code> type nonsense, just actors pointing at use cases inside of a system), from which we make a class diagram, then a relational model.</p>
  
  <p>Use Case and Class Diagram attempts: </p>
  
  <p><a href="https://i.stack.imgur.com/EoGuM.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/EoGuM.png" alt="enter image description here"></a></p>
  
  <p><a href="https://i.stack.imgur.com/56HBK.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/56HBK.png" alt="enter image description here"></a></p>
  
  <p><a href="https://i.stack.imgur.com/6W5h0.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/6W5h0.png" alt="enter image description here"></a></p>
  
  <p><a href="https://i.stack.imgur.com/T3R6i.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/T3R6i.png" alt="enter image description here"></a></p>
  
  <p>The last diagram is just me eventually thinking that maybe my use cases were the issue. </p>
  
  <p>My application lets people/restaurants list food they're willing to donate. Charities that feed the homeless request food. If there's a match, the charities can create a truck route to pick up food from all their matches. </p>
  
  <p>I'm having trouble figuring out how to represent matching, as well as if this diamond of the FoodItems and matching connecting to route makes any sense. I know inheritance is generally a bad idea in relational modeling. Is it just a matter of having FKs everywhere? I feel like I'm walking in circles.</p>