One of the questions you need to ask is: what you are going to do with all that data? If all you need is to store the data and never read it again except sequen

One of the questions you need to ask is: what you are going to do with all that data? If all you need is to store the data and never read it again except sequentially, then flat log files are probably the best way. But if you ever need to, say, calculate aggregates or do any kind of visualization, a database would probably be a better initial choice. You'll want to keep in mind that whatever you choose should be pretty flexible, because as you discover more about the analytics you're providing, you'll need to slice and dice that data differently. You won't know what data and how it will answer the questions until you know the questions.