Google Cloud Professional Data Engineer · Free practice question 6 of 12
Bigtable garbage collection by age
A Bigtable table at Marlowe Weather stores sensor values in a column family that receives a new version of each cell every minute. Only the last 30 days of versions are useful, and storage keeps growing. What should the data engineer configure?
- A.A garbage collection policy on the column family with a maximum age of 30 days
- B.A Cloud Scheduler job that deletes old rows through the Bigtable API every night
- C.A lifecycle rule on the table, like the ones used for Cloud Storage buckets
- D.A reduced number of cluster nodes
Show answer and explanation
Correct answer: A. A garbage collection policy on the column family with a maximum age of 30 days
Why: Garbage collection policies are set per column family and automatically remove cell versions that are older than a maximum age or beyond a maximum number of versions. A scheduled delete job adds code and load. Bigtable has no Cloud Storage-style lifecycle rules, and fewer nodes do not remove data.
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