Minimum Parallel Workers
A hard SQL mock interview question on DataDriven. Practice with AI-powered feedback, real code execution, and a hire/no-hire decision.
- Domain
- SQL
- Difficulty
- hard
- Seniority
- L5
Interview Prompt
We schedule batch jobs onto a shared worker pool, where each job runs from its start timestamp to its end timestamp. Find the minimum number of workers needed to run everything without conflicts: the peak number of jobs running at the same time.
Summary
Too few workers and it stalls.
How This Interview Works
- Read the vague prompt (just like a real interview)
- Ask clarifying questions to the AI interviewer
- Write your sql solution with real code execution
- Get instant feedback and a hire/no-hire decision