Server clarification

This question stems from my lack of ‘grasp’ on unitys networking system (5.1+). From my understanding ,as it pertains to MMOs, important code needs to be executed on the server side and then sent to the client. Correct me if im wrong, and I most likely am, but with unitys new networking system, once implemented, when you run the game you choose to run as a server or client… right? If I write code and attach it to objects or elements in my game how do I specify that my code is running from my server and then being sent to my client? I feel like its bottled into a single entity, servers and clients, for this networking system. Is the distinction made with RPCs? Are there many kinds of RPCs?

Also, is SQLite just as good as MySQL for running smaller MMO games?

To answer your database question, I’d look at using something like Gamesparks for your player data, which can scale up seamlessly as your MMO does.