Dynamodb hard
How does the 'Export to S3' feature dump terabytes of DynamoDB data for analysis without consuming ANY Read Capacity Units (RCUs) from the live production table?
- A It uses a hidden 'Read-Only' replica cluster that is not shared with the application.
- B PITR (Point-in-Time Recovery) Snapshots: It process the data directly from the underlying storage snapshots maintained for recovery purposes, bypassing the DynamoDB query engine and RCU metering entirely.
- C It runs the export only during the database's nightly maintenance window (UTC 00:00).
- D The export data is fetched from the DAX nodes instead of the storage nodes.
Answer: B. PITR (Point-in-Time Recovery) Snapshots: It process the data directly from the underlying storage snapshots maintained for recovery purposes, bypassing the DynamoDB query engine and RCU metering entirely.
This is a massive benefit for ETL. By leveraging the Continuous Backup (PITR) feature, AWS can read consistent 'frozen' versions of your data from the log-stream and storage snapshots. This means you can run massive exports during peak traffic hours with zero impact on your production users' latency or RCU availability.
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- DynamoDB has a strict 400KB limit on the size of a single item. What is the recommended design pattern if you need to store larger documents (e.g., 5MB PDFs)?
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- DynamoDB is a 'fully managed' serverless database. What is a primary operational benefit of this model for an engineering team?
- In 'Provisioned Capacity' mode, how is the performance budget of a DynamoDB table defined?
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