Im sure most are familiar with Facebooks 'news feed'. If not, the 'news feed' basically lists recent activity of all of your friends. I dont see how you can get this information efficiently from a DB: * Im assuming all user activity is inserted in a "actions" table. * first get a list of all your friends * then query the actions table to return recent activity where the activity belongs to someone on your friends list This can't be efficient especially considering some people have 200+ friends. So what am I missing? How do you think Facebook is implementing their "news feed". Im not asking for any specific details, just a general point in the right direction, as I cant see how they are implementing the 'news feed efficiently. Thanks.