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VLOOKUP vs INDEX MATCH in SQL

MediumSQL & Data Manipulation00:00
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Welcome to your interview.

The question is on your right: VLOOKUP vs INDEX MATCH in SQL. Take a moment with it first.

Talk your thinking through with me if you like - when you're confident, submit your answer and I'll grade it like a real screen (7/10 or better passes). Discussion and graded submissions share your five interviewer interactions, so spend them well.

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Problem

Context

You often need to enrich one dataset with values from another, such as adding a supplier name, cost center, or booking attribute to a transaction table. In SQL, that usually means choosing the right join pattern and understanding how key matching behaves.

Core question

Explain the difference between VLOOKUP and INDEX/MATCH in spreadsheet workflows, and translate that comparison into SQL terms. In your answer, describe when each lookup style is appropriate, what limitations VLOOKUP has compared with INDEX/MATCH, and how those trade-offs relate to join design, key uniqueness, and null handling in PostgreSQL.

Scope guidance

Keep your answer practical and interview-focused: define both approaches, compare their flexibility and reliability, and call out the data-shaping implications for many-to-one lookups. You do not need to write a query, but you should connect the concept to SQL data manipulation clearly.