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SQL Problem - multiple table joins and window functions

SQLmedium0.5 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
Lumiq
Key Concepts Tested
joinpartitionsqlwindow
Expert AnswerPremium
94 wordsInterview-ready
Multiple tables + window: join fact to dims, then apply window (PARTITION BY dim, ORDER BY date). Example: SELECT f.*, d.name, SUM(f.amount) OVER (PARTITION BY f.customer_id ORDER BY f.date) running_total FROM fact f JOIN dim_customer d ON f.customer_id = d.id. Use CTEs: with joined as (select ... joins), windowed as (select *, row_number() over (...) from joined) select * from windowed where ... **Why it matters**: Design choices compound at scale—wrong approach can cause 100× overhead....
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