The Query That Used to Be Fast
A medium Pipeline Design 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
- Pipeline Design
- Difficulty
- medium
- Seniority
- L5
Interview Prompt
Dashboards on a 2TB Snowflake fact table used to answer in seconds; now an analyst watches the same date- and merchant-filtered queries take minutes, far past the 30-second SLA. Design the fix: a served surface for those dashboards fed from the warehouse, plus a scheduled job that tracks p95 query duration and pages the team on regression.
Summary
Queries used to be fast. Something changed.
How This Interview Works
- Read the vague prompt (just like a real interview)
- Ask clarifying questions to the AI interviewer
- Draw your pipeline on the design canvas: sources, transforms, storage and checks
- Answer the interviewer's follow-up questions, then get a hire or no-hire decision