Basic email questionnaire, followed by recruiter phone call, followed by off-site coding challenge online.
The data challenge prep email was very misleading, though I doubt intentionally. You're given the option of doing the challenge in SQL, Python, or R. Under each language, there is a list of topics to study for the challenge.
In my case, I selected Python. The topics to study were mostly algorithmic, very comp. sci. type questions (sorting algos, data structures, etc).
However, the actual challenge was SQL table manipulation. This is not surprising at all given the position and job description, but was surprising given the prep material for the challenge. I immediately told the interviewer I wanted to do the challenge in SQL since it was a SQL problem.
I ended up slowly piecing together the solution in the end, but I don't think my pace reflected well. In the end, I didn't move on to the next round.
I have nothing against the question or the challenge. However, the prep material I was given was misled me into studying the wrong material, and had I just practiced SQL problems I might have performed better.