I had met an eBay/PayPal representative at my university's career fair. This person happened to be working on Big Data, a field I was also interested in. I was contacted by HR almost a month later, and a phone interview was quickly set up.

The phone interview was fairly easy, with questions about my resume and projects, Hadoop, MapReduce, and some very basic and standard Java and SQL questions. I was confident of clearing it and at least getting called on-site.

A week later, I was invited to come on-site, and a date was set up. I was to interview with three people back-to-back over a duration of two and a half hours.

The first interview was mostly coding. I was asked to reverse a number, then to implement the insert and delete functions of a priority queue using any data structure of my choice. I answered wrongly but was told that a Tree Map would do the job. The last question in that round was how to delete a number from a linked list.

In the second interview, I was asked a few basic SQL statements, followed by a question on normalization: what it is and how it's useful. Then, I was asked to elaborate on the differences between OLAP and OLTP.

The third interview was with the same person who had interviewed me over the phone. She asked me mostly technical, but non-coding questions, such as:

• What is the general architecture of a web application?
• Name a few design patterns and explain what a Singleton is.
• Some optimization questions involving databases.

Overall, it was an easy interview, but I was under-prepared. Although I hoped to get in, I would not have deserved it if I actually had.

There were no tough questions as such. It all depends on how well you are prepared.