Expedia Data Engineer III — SQL/Python, data modeling, director; offer

Expedia was my previous company before Amazon so I am a boomrang here. My previous feedback was good so the interview loop was cut to just three rounds.

Round 1

• This was with a data engineer III.
• It started with a SQL question about finding average session time of a user in the expedia website
• There was another question where currency exchange rates were given for dollars to rupee and I had to find out the ticket price in rupees on various dates based on the exchange value that day. The trick here was that the exchange value could change multiple times and I had to take the latest one based on the timestamp of the exchange
• Finally, there was a python question where I had to find kth smallest element in a BST. For people looking for a solution, just do an inorder traversal and get the (k-1)th element from the start of the list
• This round ended with my experience discussion at Expedia. This guy had joined about a year back so he was more interested in knowing how was Expedia 5 years ago

Round 2

• This was with a hiring manager
• This mostly concentrated around my current projects at Amazon and what they expected of me
• He also gave me small data modelling problem about consolidating hotel reviews and creating a dashboard. I had to ask questions about different attributes and what was expected of this dashboard and came up with a data model. He was pretty satisfied
• We also discussed AWS analytics stack, my experience with Redshift, Lambda, etc

Round 3

• This was a final round with the director and was very short (around 40 mins)
• She knew my work and had used it previously so she didn't have much to check
• We discussed about the new project they had started and her expectations, timelines, etc
• She asked my reason to return to EG and specific things that I would like to bring from my tenure at Amazon
• We ended on a good note and she was quite happy. I almost knew I was selected

Two days later, I got a call with an offer.