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Home/Questions/SQL/Given two dataframes (df1: id, name and df2: id, country, address, city, count), join them, filter for rows where country = 'Singapore', and pivot the output. Sort cities in descending order of population count

Given two dataframes (df1: id, name and df2: id, country, address, city, count), join them, filter for rows where country = 'Singapore', and pivot the output. Sort cities in descending order of population count

SQLmedium0.2 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
JP Morgan
Key Concepts Tested
join
Expert AnswerPremium
38 wordsInterview-ready
joined = df1.join(df2, 'id').filter(col('country')=='Singapore'). Order by population (count): .orderBy(col('count').desc()). Pivot: .groupBy('id','name').pivot('city').agg(first('count')). **Pivot cardinality**: High city count = many columns; coalesce or limit. **Broadcast** df1 if small....
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