Data Analyst · SQL · Mid-level · Theory

An analytical query against Postgres that used to run in a couple of seconds now takes ten minutes. How would you investigate, and what can you do about it?

~4 min by voice

How to approach it

The interviewer wants to see whether you can diagnose query degradation in Postgres systematically: read the plan, understand why the planner changed strategy, and propose fixes ranging from quick ones (ANALYZE, an index) to architectural ones (partitioning, materialized views).

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Topics

sql query optimization

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Answer by voice

The interviewer will ask this question and listen. Think out loud and ask for a hint if you need one. When you're done, pause or tap “That's my answer”. In about a minute, your score and the points you covered show up here.

Best with headphones · ~4 min