“People who watched this also watched” algorithm

Question

I am trying to code an algorithm that acts a bit like Amazon\'s \"People who bought this also bought\".

The difference between the two is that mine is just counting the

Answer 1

The NetFlix prize was won with a solution based on SVD. Implementing a covariance matrix in a database table is a challenge. Implementing SVD in a database might be a research problem. But most people would call it insane.