In a blog describing its data architecture, Netflix said that each time a member starts to watch a movie or TV episode, a “view” is created in its data systems and a collection of events describing that view is gathered.
Netflix’s viewing data architecture is designed for a variety of uses, ranging from user experiences to data analytics. These include recording each member’s entire viewing history in order to feed into Netflix’s recommendation algorithm, and recording how much of a movie or TV show the viewer has watched so they can continue at the same point at a later point or on a different device.
“Our current architecture evolved from an earlier monolithic database-backed application. When it was designed, the primary requirements were that it must serve the member-facing use cases with low latency and it should be able to handle a rapidly expanding set of data coming from millions of Netflix streaming devices. Through incremental improvements over 3+ years, we’ve been able to scale this to handle low billions of events per day,” said Netflix.