Data Engineer · Junior · Theory

What is a star schema, and how does it differ from a snowflake schema?

~4 min by voice

How to approach it

They're checking whether the candidate understands basic data warehouse modeling: the roles of the fact table and the dimension tables, and the trade-off between denormalization (star) and normalization (snowflake) in terms of query simplicity, speed and duplication.

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Topics

data modeling dimensional modeling

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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