Backend · Junior · Theory

What are a primary key and a foreign key? And how would you model a many-to-many relationship, for example students and courses?

~4 min by voice

How to approach it

The interviewer checks basic understanding of the relational model: why primary and foreign keys are needed, how the database enforces data integrity, and whether the candidate can properly normalize a many-to-many relationship through a junction table rather than storing lists of ids in a single column.

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Topics

sql data 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