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Given a dataset, perform transformations: Filter rows where sales > 1000, Add a new column calculating a 10% discount on sales, Group data by region and calculate total revenue.

SQLeasy0.2 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
Warner Bros Discovery
Key Concepts Tested
spark
Expert AnswerPremium
38 wordsInterview-ready
SELECT region, SUM(sales * 0.9) AS total_revenue FROM sales WHERE sales > 1000 GROUP BY region. **Filter first** to reduce rows before aggregate. **Revenue** = post-discount (sales * 0.9). **PySpark**: df.filter(col('sales')>1000).withColumn('discount', col('sales')*0.1).groupBy('region').agg(sum(col('sales')*0.9).alias('revenue'))....
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