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What file format does Delta Lake use, and why is it beneficial?

Spark/Big Dataeasy0.4 min readPremium
Frequency
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Asked at 1 company
Category
452
questions in Spark/Big Data
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88E|81M|283H
in this category
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1,863
across 7 categories
Asked at these companies
Chryselys
Expert AnswerPremium
71 wordsInterview-ready
**Format**: Parquet for data files + JSON transaction log in _delta_log. **Parquet Benefits**: Columnar; compression (snappy, zstd); predicate pushdown; schema in footer. **Delta Additions**: Transaction log for ACID; versioning; MERGE/UPDATE/DELETE; compaction (checkpoint.parquet). **Why Both**: Parquet gives storage efficiency; log gives transactional semantics. Best of both. **Scalability Trade-offs**: Log grows; checkpoint files aggregate....
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