Code reviewMediumcr-p113

Subject CorrectnessLevel Mid–Senior~18 minCommon in Code quality & review interviewsIndustries Software development

Question

Review this query to find customers with no orders.

What a strong answer looks like

Separate real bugs from style. Rank issues by severity, point at the root cause rather than the symptom, and suggest a concrete fix — specific and kind.

Learn the concepts

Talk through your review

Code to reviewsql

1SELECT * FROM customers2WHERE id NOT IN (SELECT customer_id FROM orders);

Run or narrate your approach, then ask the coach.