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Home/Questions/SQL/Write a query to calculate the day's difference between the 1st and 3rd sales of the CustomerName = 'Alice Johnson'.

Write a query to calculate the day's difference between the 1st and 3rd sales of the CustomerName = 'Alice Johnson'.

SQLmedium0.3 min readPremium
Frequency
Low
Asked at 1 company
Category
487
questions in SQL
Difficulty Split
130E|271M|86H
in this category
Total Bank
1,863
across 7 categories
Asked at these companies
Grover
Key Concepts Tested
partition
Expert AnswerPremium
64 wordsInterview-ready
WITH ranked AS (SELECT CustomerName, sale_date, ROW_NUMBER() OVER (PARTITION BY CustomerName ORDER BY sale_date) AS rn FROM sales WHERE CustomerName = 'Alice Johnson') SELECT DATEDIFF((SELECT sale_date FROM ranked WHERE rn = 3), (SELECT sale_date FROM ranked WHERE rn = 1)) AS day_diff FROM ranked LIMIT 1. Or LAG/LEAD. **Why**: Extract 1st and 3rd sale dates; compute difference....
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