VACUUM removes lakehouse files older than seven days that are no longer in use
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AnswerCorrect answer: A - VACUUM deletes files no longer referenced by the Delta log after the default seven-day retention, matching the cleanup requirement.
You have a Fabric workspace that contains an eventstream named EventStream1. EventStream1 outputs events to a table in a lakehouse. You need to remove files that are older than seven days and are no longer in use. Which command should you run?
100% of anonymous learners picked answer A.
Votes are pick records left by other test-takers — they are not the verified answer.
Community Insight
VACUUM's default retention threshold is seven days; it deletes files older than that which are no longer referenced by the Delta table log.
The VACUUM command on the lakehouse table removes files no longer referenced by the Delta log and older than the retention threshold, which defaults to seven days - exactly the cleanup the eventstream landing table needs.
Using OPTIMIZE, which only consolidates small files; removing stale unreferenced files is VACUUM's job, while COMPUTE and CLONE serve entirely different purposes.
The default retention period for the VACUUM command is 7 days, therefore it will remove files older than 7 days.
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Expert Analysis
Why the Answer Is Correct
Files written by the eventstream land as Delta table files, and older versions become unreferenced as new data arrives. The VACUUM command removes files no longer referenced by the Delta log and older than the retention threshold, whose default is seven days - precisely the requirement to remove files older than seven days that are no longer in use.
Why the Other Options Are Wrong
Option C (OPTIMIZE) consolidates small files into larger ones but never deletes stale files. Option B (COMPUTE) is not a Delta maintenance command for cleanup. Option D (CLONE) creates a copy of a table rather than removing unused files.
Community Comment Notes
The community is unanimous (A 100). GHill1982 (4 likes) notes the default retention period for the VACUUM command is 7 days, and 38578c4 links the lakehouse table maintenance documentation.