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How would you retrieve the first and last order for each customer from a sales table?

SQLmedium0.7 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
Wipro
Key Concepts Tested
partitionwindow
Expert AnswerPremium
134 wordsInterview-ready
To get first and last order per customer, use window functions MIN/MAX over order dates, or FIRST_VALUE/LAST_VALUE. Example: SELECT customer_id, order_id, order_date, FIRST_VALUE(order_id) OVER (PARTITION BY customer_id ORDER BY order_date) AS first_order_id, LAST_VALUE(order_id) OVER (PARTITION BY customer_id ORDER BY order_date ROWS BETWEEN UNBOUNDED PRECEDING AND UNBOUNDED FOLLOWING) AS last_order_id FROM sales....
The complete answer continues with detailed implementation patterns, architectural trade-offs, and production-grade considerations. It covers performance optimization strategies, common pitfalls to avoid, and real-world examples from companies like Wipro. The answer also includes follow-up discussion points that interviewers commonly explore.

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