Feature Name Intersection
A hard SQL mock interview question on DataDriven, with an AI interviewer who asks follow-up questions and a hire or no-hire decision at the end.
- Domain
- SQL
- Difficulty
- hard
- Seniority
- L4
Interview Prompt
Our ML feature store ingests the same feature names from many upstream feeds, and we're auditing the ones flowing in from both the 'user_sessions' and 'page_views' sources. For each feature name present in both, return its name along with how many rows came from each of those two sources and the most recent update date in each.
Summary
Training names versus serving names. The overlap.
How This Interview Works
- Read the vague prompt (just like a real interview)
- Ask clarifying questions to the AI interviewer
- Write and run your SQL against a real database
- Answer the interviewer's follow-up questions, then get a hire or no-hire decision