Data Analyst · SQL · Junior · Theory

Explain the difference between INNER JOIN, LEFT JOIN and FULL OUTER JOIN.

~4 min by voice

How to approach it

The interviewer checks whether the candidate understands which rows end up in the result of each kind of join and what happens to rows without a match. A plus is knowing the practical traps: row multiplication and a "broken" LEFT JOIN because of a condition in WHERE.

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Topics

sql sql joins

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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