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Ranking Trial Results with Window Functions

EasySQL & Data Manipulation00:00
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Your question is Ranking Trial Results with Window Functions. Take a moment with it on the right.

Talk me through your thinking if you like. When you're confident, submit your answer and I'll grade it like a real screen (7/10 or better passes).

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Problem

Context

Window functions come up often in analytics and reporting, especially when you need to order rows within a result set without collapsing the data. In pharmaceutical analytics, this is common when ranking sites, products, or trial metrics in systems such as Eli Lilly clinical reporting workflows.

Core question

You are asked to explain the difference between RANK(), DENSE_RANK(), and ROW_NUMBER() in SQL. Describe how each function handles ties, what output each would produce on the same ordered dataset, and when you would choose one over the others.

Scope guidance

Keep the explanation practical and interview-ready. The interviewer expects you to cover tie behavior, ordering requirements, and a simple example showing why the three functions return different results even when used over the same ORDER BY clause.