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Home/Questions/SQL/map() vs mapPartitions(): Highlight the difference between map (row-level transformation) and mapPartitions (partition-level transformation).

map() vs mapPartitions(): Highlight the difference between map (row-level transformation) and mapPartitions (partition-level transformation).

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
Capgemini
Key Concepts Tested
partition
Expert AnswerPremium
58 wordsInterview-ready
**map()**: One element → one output; row-level. Higher overhead per record. **mapPartitions()**: One partition (iterator) → iterator; enables setup/teardown per partition (e.g., DB connection); amortizes cost. **Use mapPartitions when**: DB connections, batch writes, per-partition setup. **Scalability**: mapPartitions reduces function call overhead; avoids creating connection per row....
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