Using DynamoDB GSI for Non-Key Attribute Queries

• A.Use DynamoDB Accelerator (DAX) to cache query results.
• B.Create a local secondary index (LSI) with genre as sort key and uploaded_timestamp as partition key.
• C.Increase the provisioned RCUs to 6000.
• ✓ D.Create a global secondary index (GSI) with genre as partition key and uploaded_timestamp as sort key.

Why D: Option D is correct because creating a Global Secondary Index (GSI) with genre as the partition key and uploaded_timestamp as the sort key allows efficient querying by genre and date without scanning the entire table. This directly supports the access pattern, reducing RCU consumption by using index key lookups instead of full table scans. The GSI is ideal for read-heavy workloads with occasional writes, as it offloads query traffic from the main table.

• A.Change the table's partition key to customer_id and use a composite sort key.
• B.Create a Local Secondary Index (LSI) on customer_id.
• ✓ C.Create a Global Secondary Index (GSI) with customer_id as the partition key and timestamp as the sort key.
• D.Use the Scan operation with a filter expression for customer_id and timestamp.

Why C: Option C is correct because creating a Global Secondary Index (GSI) with customer_id as the partition key and timestamp as the sort key allows efficient querying of all transactions for a given customer within a date range without redesigning the base table. The GSI provides a new access pattern with its own partition and sort keys, enabling the Query operation on customer_id and timestamp, which is far more efficient than a Scan. This approach preserves the existing table schema and supports the required query pattern with minimal overhead.

• ✓ A.Create a global secondary index with customer_id as partition key and transaction_timestamp as sort key.
• B.Enable DynamoDB Accelerator (DAX) on the table.
• C.Increase the provisioned RCUs to 10000.
• D.Change the sort key to a composite key including a tenant identifier.

Why A: Option A is correct because creating a global secondary index (GSI) with customer_id as the partition key and transaction_timestamp as the sort key allows efficient querying of transactions for a specific customer within a date range. The existing table's sort key is transaction_timestamp, but the GSI provides a separate index optimized for this access pattern, avoiding full table scans on large customer partitions. This improves query performance without requiring application code changes, as the application can query the GSI directly.

• A.Add DynamoDB Accelerator (DAX) to the table.
• B.Change the table's sort key from TransactionDate to Month.
• C.Enable DynamoDB Streams and process the stream with AWS Lambda to pre-aggregate results.
• ✓ D.Create a Global Secondary Index (GSI) with partition key AccountId and sort key Month.

Why D: Option D is correct because creating a Global Secondary Index (GSI) with partition key AccountId and sort key Month allows the analytical queries to efficiently retrieve aggregated data by account and month without scanning the entire base table. The GSI reorganizes data by month, enabling DynamoDB to use the sort key for range queries and avoid full table scans, which directly addresses the performance issue.