From transactions, return transaction_id, user_id, total_amount, and LAG(total_amount) OVER (PARTITI

A medium SQL mock interview question on DataDriven. Practice with AI-powered feedback, real code execution, and a hire/no-hire decision.

Domain

SQL

Difficulty

medium

Interview Prompt

From transactions, return transaction_id, user_id, total_amount, and LAG(total_amount) OVER (PARTITION BY user_id ORDER BY transaction_date) AS prev_amount. Order by user_id, transaction_date.

How This Interview Works

1. Read the vague prompt (just like a real interview)
2. Ask clarifying questions to the AI interviewer
3. Write your sql solution with real code execution
4. Get instant feedback and a hire/no-hire decision