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Describe how partitioning helps improve query performance in a large dataset.

SQLmedium0.4 min readPremium
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Asked at 1 company
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1,863
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Disney+ Hotstar
Key Concepts Tested
bigquerypartitionsnowflake
Expert AnswerPremium
82 wordsInterview-ready
**Architectural Logic**: Partitioning enables partition pruning—skip irrelevant data, reduce I/O and cost. **Mechanism**: Data split by partition column (e.g., date); stored in separate physical units. Query with `WHERE sale_date BETWEEN '2024-01-01' AND '2024-01-31'` reads only January partitions. **Why**: Full scan of 1TB → scan 30GB for one month; 30x reduction. **Scalability**: Partition count matters—10K+ partitions can hurt metadata overhead....
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