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What is the purpose of the VACUUM command in Delta Lake?

Spark/Big Dataeasy0.4 min readPremium

**Purpose**: Removes files older than retention (default 7 days) that are no longer in current table state. Reclaims storage. **Why**: Delta keeps all file versions for time travel. Old files accumulate. VACUUM deletes reclaimable files. **Trade-off**: Removes time-travel...

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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
Total Bank
1,863
across 7 categories
Asked at these companies
Puma

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Expert Answer
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Purpose: Removes files older than retention (default 7 days) that are no longer in current table state. Reclaims storage.

Why: Delta keeps all file versions for time travel. Old files accumulate. VACUUM deletes reclaimable files.

Trade-off: Removes time-travel capability beyond retention. Ensure no active time-travel queries.

Syntax: VACUUM table_name or VACUUM table_name RETAIN 168 HOURS.

Scalability Trade-offs: Expensive on huge tables; run during maintenance.

Cost Implications: Un-vacuumed = 2–5x storage. Schedule weekly.

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