No One Left Behind
A medium Python mock interview question on DataDriven. Practice with AI-powered feedback, real code execution, and a hire/no-hire decision.
- Domain
- Python
- Difficulty
- medium
- Seniority
- L4
Interview Prompt
You're reconciling two exported tables given as lists of dicts, `left` and `right`, that share a `key` field. Combine them the way a SQL left join does: keep every `left` record and merge in the fields of the matching `right` record. Every output row should expose the same set of right-side columns, so a row with nothing to fill one carries `None` there.
Summary
Every record stays; fill the gaps where a match exists.
How This Interview Works
- Read the vague prompt (just like a real interview)
- Ask clarifying questions to the AI interviewer
- Write your python solution with real code execution
- Get instant feedback and a hire/no-hire decision