To the interviewer - Were you expecting a researcher with double PHD having all theories memorized or you wanted a developer who can code and get things done. I was interviewed at bobble over phone call. I was told that it is just screening round and questions will be related to product review and analysis. The process started with the description of my past experience. I had experience in php/mysql only a year. and the first question I was asked is about storing and retrieving a hierarchical data structure in database. It was taking me time to write the query for that so he asked a simpler query to find percentage of given gender in a class. I answered that then he came back to previous question expecting me to write SQL queries using "modified preorder tree traversal’ algorithm". Then I was given half an hour to write query for that. after 45mins I called back him. then he reverted. I then answered him the select query for that question. Then he asked how php session works. Its my bad that I only had knowledge of implementation aspect of sessions not the internals of it as how the session id is stored in cookie and referenced again by Apache. That's it.