Let's take Facebook out of the picture, it's too hot a topic. Let's talk about the datawarehouse of some other big tech company like amazon or adcrunch. The DW

Let's take Facebook out of the picture, it's too hot a topic. Let's talk about the datawarehouse of some other big tech company like amazon or adcrunch. The DW can be queried by user but each query might take 10 mins to evaluate, so it can't be used for realtime UIs. Instead you would have to denormalize the data to display to a user. That's a project, it might take a few months.