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Given a table with sales data, write a query to find consecutive days with decreasing revenue.

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
Uber
Key Concepts Tested
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Expert AnswerPremium
63 wordsInterview-ready
**LAG approach**: WITH t AS (SELECT date, revenue, LAG(revenue) OVER (ORDER BY date) AS prev_rev FROM sales) SELECT date, revenue FROM t WHERE revenue < prev_rev AND prev_rev IS NOT NULL. **Consecutive pairs**: Self-join ON a.date = b.date + 1 WHERE a.revenue < b.revenue. **N consecutive**: Extend with multiple LAG or recursive pattern....
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