Elevate your expertise in AWS DynamoDB with these 30 multiple-choice questions (MCQs) focusing on advanced features and integrations. Learn about DynamoDB Streams, TTL for data expiry, ACID transactions, backup and recovery, and DAX for caching. These AWS DynamoDB MCQ questions and answers are perfect for mastering this NoSQL database’s real-world applications and preparing for exams.
Chapter 5: Advanced Features and Integrations
1. DynamoDB Streams: Real-Time Data Processing
What is the primary purpose of DynamoDB Streams? a. To trigger backups b. To log query history c. To enable real-time data processing d. To increase storage capacity
How long are DynamoDB Streams records retained by default? a. 7 days b. 24 hours c. 48 hours d. 3 days
Which AWS service can be integrated with DynamoDB Streams for processing changes? a. AWS Lambda b. Amazon S3 c. AWS CloudFormation d. Amazon RDS
What is a key feature of a stream-enabled DynamoDB table? a. Provides point-in-time recovery b. Tracks all data changes in the table c. Automatically archives deleted items d. Enables high write throughput
Which operation can trigger a DynamoDB Stream? a. Data retrieval b. Table deletion c. Data modification d. Read operation
2. TTL (Time to Live) for Data Expiry
What does the TTL feature in DynamoDB do? a. Enables point-in-time recovery b. Deletes expired items automatically c. Enhances query speed d. Creates automatic backups
How is the expiration time for items set in DynamoDB TTL? a. By using a predefined timestamp attribute b. By assigning a priority level c. By setting an auto-delete policy d. By specifying an event trigger
Which format is used for TTL expiration values? a. ISO 8601 b. UNIX epoch time c. UTC string d. Local timezone
What happens to expired items in a DynamoDB table? a. They are deleted automatically in the background b. They are marked as archived c. They generate a DynamoDB Stream event d. They are stored in a backup
Why should TTL be used in DynamoDB? a. To reduce storage costs b. To improve read throughput c. To enhance item replication d. To simplify query operations
3. Transactions: ACID Support in DynamoDB
What is a key benefit of using transactions in DynamoDB? a. Enables eventual consistency b. Guarantees ACID properties c. Improves table scaling d. Increases data retention
How many operations can be included in a single DynamoDB transaction? a. Up to 10 b. Up to 20 c. Unlimited d. Up to 5
Which DynamoDB SDK method is used to write transactional items? a. BatchWriteItem b. TransactWriteItems c. PutItem d. UpdateItem
What happens if one operation in a DynamoDB transaction fails? a. Only the failing operation is rolled back b. The entire transaction is rolled back c. The successful operations are retained d. The transaction is retried automatically
Which of the following is an example of a DynamoDB transaction use case? a. Read-heavy applications b. Real-time analytics c. Multi-item update consistency d. Large-scale data migrations
4. Backup and Restore, Point-In-Time Recovery
What does DynamoDB Point-In-Time Recovery (PITR) allow you to do? a. Automatically scale tables b. Restore data to a previous state c. Archive data indefinitely d. Schedule automatic exports
What is the retention period for PITR in DynamoDB? a. 35 days b. 7 days c. 24 hours d. 14 days
How are backups created in DynamoDB? a. Through manual API calls or AWS Management Console b. Automatically triggered after table creation c. As part of a TTL policy d. Using CloudFormation templates
What type of backups does DynamoDB provide? a. Incremental backups only b. Full table backups c. Selective backups d. Query-specific backups
Which of the following is a limitation of DynamoDB on-demand backups? a. Cannot back up tables larger than 1 TB b. Only available for on-demand tables c. Does not support global tables d. Does not restore indexes
5. DynamoDB Accelerator (DAX) for Caching
What is the purpose of DynamoDB Accelerator (DAX)? a. To enhance query speed with in-memory caching b. To replicate tables across regions c. To enable automatic backups d. To store query logs
How does DAX improve application performance? a. By reducing the number of write operations b. By caching frequently accessed data c. By scaling read capacity units automatically d. By minimizing TTL expiration delays
Which API calls are accelerated by DAX? a. Write-heavy operations b. All read operations c. Query and GetItem calls d. Backup and Restore operations
Which feature is unique to DAX? a. Allows asynchronous query execution b. Provides single-digit millisecond latency c. Supports unlimited caching size d. Enables data encryption
What is required to integrate DAX with a DynamoDB application? a. Updating the DynamoDB SDK to support DAX b. Creating a global secondary index c. Enabling TTL on all items d. Configuring DynamoDB Streams
What happens if an item is not found in the DAX cache? a. The application throws an error b. The request is automatically forwarded to DynamoDB c. The cache is refreshed from a backup d. The operation is retried
How can DAX reduce costs for read-heavy applications? a. By replacing DynamoDB tables with DAX clusters b. By reducing read capacity unit (RCU) consumption c. By automatically deleting expired data d. By enabling write operation optimization
Which DynamoDB API operation is not supported by DAX? a. BatchGetItem b. Query c. Scan d. TransactWriteItems
What is a potential limitation of DAX? a. Does not support on-demand tables b. Limited to specific AWS regions c. Requires additional configuration for encryption d. Inconsistent performance for write-heavy workloads
How does DAX handle eventual consistency? a. By maintaining a write-through cache b. By providing strongly consistent reads only c. By ensuring immediate replication d. By relying on eventual consistency of DynamoDB
Answer Key
QNo
Answer
1
c. To enable real-time data processing
2
b. 24 hours
3
a. AWS Lambda
4
b. Tracks all data changes in the table
5
c. Data modification
6
b. Deletes expired items automatically
7
a. By using a predefined timestamp attribute
8
b. UNIX epoch time
9
a. They are deleted automatically in the background
10
a. To reduce storage costs
11
b. Guarantees ACID properties
12
a. Up to 10
13
b. TransactWriteItems
14
b. The entire transaction is rolled back
15
c. Multi-item update consistency
16
b. Restore data to a previous state
17
a. 35 days
18
a. Through manual API calls or AWS Management Console
19
b. Full table backups
20
d. Does not restore indexes
21
a. To enhance query speed with in-memory caching
22
b. By caching frequently accessed data
23
c. Query and GetItem calls
24
b. Provides single-digit millisecond latency
25
a. Updating the DynamoDB SDK to support DAX
26
b. The request is automatically forwarded to DynamoDB
27
b. By reducing read capacity unit (RCU) consumption
28
d. TransactWriteItems
29
d. Inconsistent performance for write-heavy workloads