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Discuss Delta Logs file format and its significance.

Spark/Big Dataeasy0.4 min readPremium
Frequency
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Asked at 1 company
Category
452
questions in Spark/Big Data
Difficulty Split
88E|81M|283H
in this category
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1,863
across 7 categories
Asked at these companies
Hexaware
Expert AnswerPremium
75 wordsInterview-ready
**Why Delta Log matters**: Enables ACID, time travel, schema evolution. **Format**: JSON files in `_delta_log/`; each transaction = new file. Records add/remove file actions, metadata. **Significance**: Single source of truth for table state; concurrent readers see consistent snapshot. **Scalability trade-offs**: Log grows; VACUUM removes old files beyond retention. **Cost implications**: Log = small storage; many small transactions = many small log files....
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