- Authors

- Name
- Youngju Kim
- @fjvbn20031
Exam Overview
| Item | Details |
|---|---|
| Duration | 180 minutes |
| Questions | 65 |
| Passing Score | 750 / 1000 |
| Question Types | Single answer, Multiple answer |
| Exam Cost | USD 300 |
Domain Breakdown
| Domain | Weight |
|---|---|
| Domain 1: Collection | 18% |
| Domain 2: Storage and Data Management | 22% |
| Domain 3: Processing | 24% |
| Domain 4: Analysis and Visualization | 18% |
| Domain 5: Data Security | 18% |
AWS Data Analytics Services Ecosystem
[Data Sources]
├── Streaming: Kinesis Data Streams → Kinesis Data Analytics (Flink)
│ → Kinesis Data Firehose → S3/Redshift/OpenSearch
├── Batch: DMS, Snow Family, Direct Connect
└── SaaS: AppFlow
[Storage]
├── Data Lake: S3 + Lake Formation
├── Data Warehouse: Redshift (RA3, Spectrum)
├── NoSQL: DynamoDB
└── Search: OpenSearch Service
[Processing]
├── Large-scale Batch: EMR (Spark, Hive, Flink)
├── Serverless ETL: AWS Glue
└── Lightweight Transforms: Lambda
[Analysis & Visualization]
├── Serverless Query: Athena
├── BI Dashboards: QuickSight (SPICE)
└── Exploratory Analysis: OpenSearch Dashboards
[Security]
├── Access Control: Lake Formation, IAM
├── Encryption: KMS, SSE
└── Network: VPC Endpoints, PrivateLink
Practice Questions
Domain 1: Collection
Q1. You need to collect IoT sensor data at 50,000 events per second. Data must be ordered and replayable for 24 hours. Which service is most appropriate?
A) Kinesis Data Firehose B) Kinesis Data Streams C) SQS FIFO Queue D) Amazon MSK
Answer: B
Explanation: Kinesis Data Streams provides partition-key-based ordering, configurable data retention up to 7 days (default 24 hours), and real-time replay capability. Firehose does not support replay, and SQS FIFO has throughput limits.
Q2. Your Kinesis Data Streams consumers are hitting the shared read throughput limit. Multiple consumer applications read from the same stream. How do you improve read throughput per consumer?
A) Increase the number of shards B) Enable Enhanced Fan-Out C) Switch to Provisioned capacity mode D) Reduce GetRecords API call frequency
Answer: B
Explanation: Enhanced Fan-Out provides each registered consumer with a dedicated 2 MB/s throughput per shard. Standard GetRecords shares the 2 MB/s per shard across all consumers, while Enhanced Fan-Out gives each consumer its own dedicated pipe.
Q3. You want to use Kinesis Data Firehose to convert JSON records to Parquet and route them to different S3 prefixes based on a field value. What is the correct configuration?
A) Lambda transformation + prefix expressions B) Format Conversion + Dynamic Partitioning C) Integrate with Glue ETL D) Use S3 Object Lambda
Answer: B
Explanation: Kinesis Data Firehose Format Conversion transforms JSON to Parquet/ORC using the Glue Data Catalog schema. Dynamic Partitioning extracts values from records using jq expressions or inline parsing to build dynamic S3 prefixes. Both features are configured natively in Firehose.
Q4. You need to implement continuous CDC replication from an on-premises Oracle database to Amazon Redshift. What is the most appropriate approach?
A) Use AWS Glue ETL to periodically copy full tables B) Use AWS DMS with a continuous replication task C) Use Kinesis Data Streams + Lambda D) Initial load with Snowball, then Direct Connect
Answer: B
Explanation: AWS DMS reads transaction logs from the source database to implement CDC. After an initial full load, the ongoing replication task continuously synchronizes changes. For heterogeneous migration (Oracle to Redshift), use SCT (Schema Conversion Tool) alongside DMS to convert the schema.
Q5. You need to transfer petabytes of data from on-premises to S3. Internet bandwidth is 1 Gbps and transfer would take months. What is the most cost-effective and fast approach?
A) Build an AWS Direct Connect dedicated line B) Order multiple Snowball Edge Storage Optimized devices C) Use AWS Snowmobile D) Enable S3 Transfer Acceleration
Answer: C
Explanation: For petabyte-scale (100 PB+) data transfers, Snowmobile is the appropriate choice. Each Snowmobile can hold up to 100 PB. Internet or Direct Connect transfers at this scale would take too long and cost too much. Snowball Edge holds up to 80 TB per device, requiring many devices for petabyte-scale.
Q6. You are choosing between Amazon MSK and Kinesis Data Streams. Your team has existing applications built on Apache Kafka APIs and requires long message retention (up to 1 year). Which service is appropriate?
A) Kinesis Data Streams — better scalability B) Amazon MSK — Kafka compatibility and long retention support C) Kinesis Data Firehose — fully managed D) SQS — longer message retention
Answer: B
Explanation: Amazon MSK is a fully managed Apache Kafka service, enabling existing Kafka client code to work without modification. Retention can be set to unlimited. Kinesis supports up to 365 days retention but is not compatible with the Kafka API.
Q7. ProvisionedThroughputExceededException errors occur frequently on your Kinesis Data Streams. Analysis of the partition key distribution shows concentration on specific keys. What is the solution?
A) Double the number of shards B) Add a random prefix to the partition key for uniform shard distribution C) Enable Enhanced Fan-Out D) Disable KPL aggregation
Answer: B
Explanation: Hot shard problems (write concentration on specific partition keys) are resolved by distributing the partition key. Prepending a random prefix (e.g., a number in range 0 to N) distributes records across multiple shards. On the read side, you must fan-out across all shards to reconstruct the full dataset.
Q8. In Kinesis Data Analytics (Apache Flink) for real-time anomaly detection, you need to compare current values against the past 30 minutes. Which Flink windowing feature should you use?
A) Tumbling Window B) Sliding Window C) Session Window D) Global Window
Answer: B
Explanation: A Sliding Window has a fixed size that moves forward at a defined interval. For example, a 30-minute window sliding every 1 minute always evaluates the most recent 30 minutes of data. Tumbling Windows are non-overlapping fixed intervals.
Domain 2: Storage and Data Management
Q9. You want to optimize Athena query performance over a partitioned S3 data lake. Data is appended daily and queries typically filter by date range and region code. What is the optimal partitioning strategy?
A) Single partition: year/month/day B) Composite partition: year/month/day/region C) No partitioning, use Athena Partition Projection D) Store all data under a single prefix with compression
Answer: B
Explanation: Aligning the partitioning scheme with query patterns minimizes data scanned by Athena. A year/month/day/region hierarchy enables partition pruning for both filter conditions simultaneously, maximizing performance.
Q10. In AWS Lake Formation, you need to restrict specific columns in a table to be visible only to specific IAM roles. What is the correct approach?
A) Restrict access via S3 bucket policy on specific prefixes B) Apply Glue catalog resource-based policies at the table level C) Configure Lake Formation column-level security D) Set query filters per Athena workgroup
Answer: C
Explanation: Lake Formation provides fine-grained access control at the table, column, and row level. Column-level security restricts which columns are visible to specific IAM roles or users. S3 bucket policies only control at the file level and cannot enforce column-level restrictions.
Q11. Redshift large-table join performance is degrading. Both tables have billions of rows and are frequently joined. What is the optimal distribution style combination?
A) Both tables: EVEN distribution B) Both tables: ALL distribution C) Large fact table: KEY distribution (join key); small dimension table: ALL distribution D) Both tables: AUTO distribution
Answer: C
Explanation: Using KEY distribution on both fact tables with the same join key means data is co-located on the same nodes, enabling local joins without network redistribution. Small dimension tables with ALL distribution are broadcast to every node, avoiding broadcast join overhead for large-to-small joins.
Q12. Your DynamoDB table stores user orders with UserID (partition key) and OrderDate (sort key). What is the most efficient way to query all orders for a specific user after a specific date?
A) Use a Scan with FilterExpression B) Use a Query with KeyConditionExpression specifying UserID and an OrderDate range C) Create a GSI and query it D) Use DynamoDB Streams + Lambda to maintain an index
Answer: B
Explanation: Using a Query with the table's primary key (UserID as partition key, OrderDate as sort key) is the most efficient access pattern. Set KeyConditionExpression to UserID = :uid AND OrderDate >= :date. Scans read the entire table and are highly inefficient.
Q13. What is the primary reason to use Redshift RA3 nodes?
A) To independently scale compute and storage B) For maximum query performance through in-memory caching C) To automatically parallelize queries D) To directly access data in S3
Answer: A
Explanation: Redshift RA3 nodes separate compute and storage, allowing each to scale independently. Frequently accessed data is cached on local NVMe SSD, while the rest resides in Redshift Managed Storage (RMS) backed by S3. You can grow storage without increasing compute costs.
Q14. You need to manage aging index data in OpenSearch Service cost-effectively. The last 7 days are frequently queried, 30 days to 1 year occasionally, and beyond 1 year rarely. What is the optimal storage tier configuration?
A) Keep all data in Hot storage B) Transition data: Hot → UltraWarm → Cold storage C) Export data older than 30 days to S3 D) Use Index State Management to delete data after 30 days
Answer: B
Explanation: OpenSearch Service provides Hot (fast NVMe SSD), UltraWarm (S3-backed, lower cost), and Cold (lowest cost) storage tiers. Use Index State Management (ISM) to define automated policies that move indices through these tiers based on age, balancing performance and cost.
Q15. You applied Lake Formation Governed Tables to your S3 data lake. What is the primary benefit?
A) Automatic file compression reduces storage costs B) ACID transaction support and automatic data compaction C) Real-time streaming data ingestion D) Automatic column-level encryption
Answer: B
Explanation: Lake Formation Governed Tables provide ACID transactions (atomicity, consistency, isolation, durability) on S3 data, ensuring data consistency during concurrent reads and writes. Automatic compaction resolves the small files problem. Row-level security is also supported.
Q16. What is the most effective way to maximize Redshift Spectrum performance when querying S3 data lake?
A) Store S3 data in CSV format B) Store S3 data in Parquet format with partitioning C) Maximize the number of Redshift cluster nodes D) Limit each Spectrum slice to one file
Answer: B
Explanation: Redshift Spectrum achieves best performance with columnar formats like Parquet or ORC. Column pruning (reading only required columns) combined with partition pruning (reading only required partitions) drastically reduces the data scanned. CSV requires reading entire files.
Domain 3: Processing
Q17. You want to minimize EMR cluster costs using Spot Instances while minimizing the risk of job failure. What is the correct configuration?
A) Use Spot for master, core, and task nodes B) Use On-Demand for master and core nodes; Spot only for task nodes C) Use On-Demand for master; Spot for core and task nodes D) Use Reserved Instances for all nodes
Answer: B
Explanation: The master node manages the cluster, and core nodes store HDFS data. Using On-Demand for both master and core nodes ensures stability and data durability. Task nodes (additional compute only, no HDFS storage) can safely use Spot. Spot interruption of task nodes does not cause data loss.
Q18. What is the most accurate description of the difference between AWS Glue DynamicFrame and Apache Spark DataFrame?
A) DynamicFrame has no schema and handles all data types B) DynamicFrame tolerates schema inconsistencies (choice type) and provides AWS-specific transforms like relationalize C) DataFrame is always faster so DynamicFrame should be avoided D) DynamicFrame supports only structured streaming
Answer: B
Explanation: AWS Glue DynamicFrame represents columns with mixed types as a "choice" type. It provides AWS-specific transformations such as resolveChoice() and relationalize(). For performance-critical paths, you can convert DynamicFrame to DataFrame, process it, and convert back.
Q19. A Glue Crawler re-crawling your entire S3 partitioned dataset each time a new partition is added is inefficient. What is the alternative?
A) Schedule the Glue Crawler to run every minute B) Use Athena MSCK REPAIR TABLE or ADD PARTITION C) Use Lake Formation blueprints to auto-manage partitions D) Use an S3 event notification to trigger Lambda that updates Glue Catalog partitions
Answer: D
Explanation: An S3 ObjectCreated event triggers a Lambda function that calls glue:BatchCreatePartition to add only the new partition to the Glue Catalog. This is the most efficient approach. Athena MSCK REPAIR TABLE also works but becomes slower as the partition count grows.
Q20. What is the key difference between EMR Serverless and EMR on EC2?
A) EMR Serverless maintains a permanent cluster; EMR on EC2 uses ephemeral clusters B) EMR Serverless automatically scales without cluster provisioning and has no idle costs C) EMR Serverless only supports Hive, not Spark D) EMR on EC2 is always more cost-effective
Answer: B
Explanation: EMR Serverless automatically provisions resources when a job is submitted without you managing any cluster. There are no charges when no jobs are running. It supports Spark, Hive, and other frameworks. It is ideal for intermittent batch workloads.
Q21. What is the primary use case for AWS Glue DataBrew?
A) Large-scale distributed Spark ETL processing B) No-code visual data preparation and cleaning C) Real-time streaming data transformation D) Data catalog metadata management
Answer: B
Explanation: AWS Glue DataBrew provides a visual, code-free interface for exploring, cleaning, and normalizing data. It offers 250+ pre-built transformations and supports data quality rule definitions and profiling. It is designed for data analysts and data scientists who prefer visual tooling.
Q22. In a Step Functions-orchestrated data pipeline, you need to implement automatic retry logic when an EMR job fails. What is the correct approach?
A) Poll EMR status with a Lambda function and restart on failure B) Add a Retry block to the Step Functions state definition C) Detect EMR failure with a CloudWatch Alarm and send SNS notification D) Wrap the EMR job in a Glue Workflow
Answer: B
Explanation: Adding a Retry block to each task state in Step Functions enables automatic retries for specified error types. You can configure the number of retries, interval, and backoff rate. A Catch block handles the final failure case with an alternative path.
Q23. An AWS Glue ETL job produces thousands of small files in S3 after processing. How do you resolve this small files problem?
A) Reduce the number of Glue workers B) Use coalesce() or repartition() to control the output partition count before writing C) Use S3 Lifecycle policies to automatically delete small files D) Merge files using Kinesis Firehose
Answer: B
Explanation: In Spark, coalesce(N) reduces the number of partitions without a shuffle (may produce uneven sizes), while repartition(N) redistributes evenly (incurs shuffle). Using either before a write operation controls the number of output files. coalesce is generally preferred for merging small files.
Q24. How do you increase the processing speed of a Lambda function used as an event source for Kinesis Data Streams?
A) Increase Lambda function memory B) Increase the Parallelization Factor per shard C) Decrease the batch size D) Increase Lambda reserved concurrency
Answer: B
Explanation: The Parallelization Factor (1–10) for the Kinesis-Lambda event source mapping allows multiple concurrent Lambda invocations per shard. The default value of 1 means one concurrent Lambda execution per shard. Setting it to 10 enables up to 10 parallel Lambda invocations per shard simultaneously.
Domain 4: Analysis and Visualization
Q25. You want to minimize Athena costs for frequently executed queries by reusing previous results. Which Athena feature should you use?
A) Athena Query Result Reuse B) Athena Federated Query C) CTAS to save results D) Athena workgroup query queuing
Answer: A
Explanation: Athena Query Result Reuse reuses previous query results for identical queries within a configurable period (up to 7 days). No scan charges are incurred for reused results. This is highly effective for repeated queries on static data.
Q26. You want to avoid managing partition metadata in the Glue Catalog for hourly partitioned S3 data queried with Athena. What is the most efficient approach?
A) Run MSCK REPAIR TABLE every hour B) Configure Athena Partition Projection C) Run ALTER TABLE ADD PARTITION every hour D) Use Lake Formation for automatic partition management
Answer: B
Explanation: Athena Partition Projection computes partition values dynamically from rules defined in the table properties, without storing partition metadata in the Glue Catalog. It is especially effective for regular patterns (dates, numeric ranges) and eliminates partition registration overhead.
Q27. An Athena EXPLAIN output for a Redshift query shows DS_DIST_ALL_NONE. What does this mean?
A) Both tables use KEY distribution for efficient co-located joins B) One table uses ALL distribution so no data redistribution is needed for the join C) EVEN distribution requires data redistribution D) No distribution key, broadcast join not possible
Answer: B
Explanation: DS_DIST_ALL_NONE means one table in the join uses ALL distribution (copied to every node), so no redistribution is needed. This is an efficient join pattern. DS_DIST_ALL_INNER indicates redistribution cost is involved.
Q28. You want to quickly visualize a dataset with hundreds of millions of rows in QuickSight. Data is updated daily. What is the optimal configuration?
A) Direct Query mode connected to Redshift B) Import data into SPICE with a scheduled refresh C) Direct query of S3 data via Athena D) Use QuickSight Paginated Reports
Answer: B
Explanation: SPICE (Super-fast Parallel In-memory Calculation Engine) is QuickSight's in-memory storage that enables ultra-fast queries and visualization even for hundreds of millions of rows. Scheduled refresh keeps SPICE data current. Direct Query mode is real-time but may be slow for very large datasets.
Q29. Long-running Redshift queries are blocking short queries. How do you best resolve this with Workload Management (WLM)?
A) Add nodes to the cluster B) Enable Short Query Acceleration (SQA) C) Assign equal priority to all queries D) Schedule long-running queries for nighttime
Answer: B
Explanation: Redshift Short Query Acceleration (SQA) uses machine learning to predict short-running queries and run them in a dedicated priority queue. It requires no separate WLM queue configuration and automatically optimizes environments where short and long queries coexist.
Q30. You need to implement Row-Level Security in QuickSight so that sales representatives can only see data for their own region. What is the correct approach?
A) Create a separate dataset per sales representative B) Apply a QuickSight RLS (Row-Level Security) rule to the dataset C) Restrict S3 data access via IAM policies D) Use Athena views to filter data per user
Answer: B
Explanation: QuickSight RLS attaches a rules file (CSV or another dataset) mapping users/groups to filter values to a dataset. Data is automatically filtered based on the logged-in user. A single dataset serves all representatives, each seeing only their own region's data.
Q31. What is the primary scenario for using Athena Federated Query?
A) Join S3 data lake with RDS, DynamoDB, and other heterogeneous sources in a single SQL statement B) Query Redshift and S3 data together C) Process S3 buckets across multiple AWS accounts in a single query D) Analyze real-time streaming data with SQL
Answer: A
Explanation: Athena Federated Query uses Lambda-based data source connectors to run SQL on data sources beyond S3 (RDS, DynamoDB, ElastiCache, CloudWatch, Redis, etc.). Multiple heterogeneous sources can be joined in a single query, enabling integrated analytical workloads without data movement.
Q32. When indexing large volumes of log data in OpenSearch Service, how do you optimize indexing performance?
A) Reduce the Refresh Interval to 1 second B) Use the Bulk API and increase the Refresh Interval C) Call the Index API for each document individually D) Maximize the number of shards
Answer: B
Explanation: The Bulk API batches multiple documents per request, reducing network overhead. Increasing the Refresh Interval (e.g., from the default 1 second to 30 seconds or more) reduces segment creation frequency and significantly improves indexing throughput. Call a manual refresh after the bulk load completes.
Domain 5: Data Security
Q33. You need to ensure that specific departments can only access specific tables in your S3 data lake. Should you use Lake Formation or S3 bucket policies?
A) S3 bucket policies alone provide fine-grained data access control B) Lake Formation data permissions for table/column/row-level access control C) IAM policies to control Glue Catalog access D) S3 Access Points to control access by prefix
Answer: B
Explanation: Lake Formation integrates with the Glue Data Catalog to provide logical table, column, and row-level fine-grained access control. Permissions are based on logical data structure rather than physical S3 file paths. S3 bucket policies only control at the file/prefix level and cannot enforce column or row-level restrictions.
Q34. You need to enable in-transit encryption for Kinesis Data Streams using an AWS-managed key. What is the correct approach?
A) Enable S3 server-side encryption (SSE-S3) B) Enable Server-Side Encryption (SSE) on the Kinesis stream — select the aws/kinesis KMS key C) Create a customer-managed KMS key (CMK) and attach it to Kinesis D) Use client-side encryption before sending data
Answer: B
Explanation: Kinesis Data Streams supports server-side encryption (SSE). Selecting the AWS-managed key (aws/kinesis) encrypts all stream data with KMS without additional configuration. A customer-managed key (CMK) provides more granular key policy control but requires additional setup.
Q35. Your Redshift cluster is deployed in a VPC. You want COPY commands loading data from S3 to never traverse the public internet. What should you configure?
A) Assign a public IP to the Redshift cluster B) Route S3 traffic through a NAT Gateway C) Configure a VPC endpoint (gateway endpoint) for S3 D) Use Direct Connect for AWS network connectivity
Answer: C
Explanation: An S3 gateway VPC endpoint routes Redshift COPY/UNLOAD operations through the AWS private network. S3 traffic does not traverse the internet gateway or NAT Gateway, improving security and eliminating data transfer costs.
Q36. How do you encrypt metadata (table definitions, partition information) stored in the AWS Glue Data Catalog?
A) It is automatically handled by S3 server-side encryption B) Enable metadata encryption in Glue Security Configuration C) Directly attach a KMS key to Glue Catalog tables D) Use Lake Formation to control metadata access
Answer: B
Explanation: AWS Glue Security Configuration enables encryption of Glue Data Catalog metadata with a KMS key. ETL job data encryption (at rest, in transit) and job bookmark encryption are also configured in Security Configuration.
Q37. Your analytics team needs access to the production S3 data lake, but PII must be masked. What is an efficient solution?
A) Maintain a separate S3 bucket copy with PII removed for the analytics team B) Lake Formation column-level security + S3 Object Lambda for dynamic masking C) Deny full bucket access in the analytics team IAM role, allow only specific prefixes D) Use Glue ETL to generate a daily PII-free dataset
Answer: B
Explanation: Lake Formation column-level security blocks PII columns. S3 Object Lambda can dynamically mask PII at read time using a Lambda function. This approach avoids duplicating data and allows centralized management of masking logic.
Q38. For compliance auditing, your organization must log all query activity on Redshift. What is the correct configuration?
A) Use CloudTrail to record Redshift API calls B) Enable Redshift Audit Logging to S3 C) Use VPC Flow Logs to record Redshift network traffic D) Use CloudWatch Logs to record Redshift connections
Answer: B
Explanation: Redshift Audit Logging writes connection logs, user activity logs, and user logs to S3. The user activity log records every executed SQL query. This provides complete Who/What/When information needed for compliance auditing. CloudTrail captures only Redshift API calls.
Advanced Scenarios
Q39. An e-commerce company needs to analyze real-time purchase events. Requirements: 1) 100,000 events/sec, 2) real-time fraud detection within 100ms, 3) daily purchase reports, 4) 3-year data retention. Choose the architecture.
A) Kinesis Firehose → S3 → Athena (satisfies all requirements) B) Kinesis Data Streams → Lambda (real-time fraud detection) + Firehose → S3 (batch) + Glue + Redshift (reports) C) MSK → Spark Streaming → DynamoDB D) SQS → Lambda → RDS → QuickSight
Answer: B
Explanation: Kinesis Data Streams feeds Lambda for sub-100ms fraud detection and simultaneously routes to Firehose for S3 storage. Glue ETL processes S3 data and loads it into Redshift for daily reports. S3 Intelligent-Tiering manages 3-year retention cost-effectively.
Q40. A healthcare organization needs to analyze electronic health records on AWS. Which two security configurations are required for HIPAA compliance? (Select 2)
A) Enable S3 server-side encryption (KMS) B) Enforce in-transit encryption (SSL/TLS) for Redshift C) Distribute data via CloudFront D) Store data in a public S3 bucket E) Use Kinesis streams without encryption
Answer: A, B
Explanation: HIPAA compliance requires encryption at rest (S3 SSE-KMS) and in transit (SSL/TLS). VPC deployment, access logging, and audit trails are also required. Options D and E violate HIPAA requirements, and CloudFront is not directly related to HIPAA data protection.
Q41. For a data lake migration project, you need to move petabytes of on-premises Hadoop HDFS data to S3, including the Hive Metastore. What is the correct approach?
A) Copy data with S3 DistCp, regenerate metadata with Glue Crawler B) Physical data transfer with Snowball family, schema conversion with SCT C) Copy data with AWS DataSync, migrate Hive Metastore by importing into Glue Catalog D) Use DMS for the entire migration
Answer: C
Explanation: AWS DataSync efficiently transfers large datasets from on-premises HDFS to S3 with parallel transfer and automatic integrity verification. The Glue Data Catalog is compatible with the Hive Metastore and supports importing metadata. EMR can run existing Hive queries against the Glue Catalog.
Q42. You used Athena CTAS to convert CSV data to Parquet with partitioning. What additional step maximizes performance?
A) Minimize file sizes to increase file count B) Optimize file sizes to 128 MB–1 GB to maintain splittable format C) Disable compression to speed up file reads D) Increase partitioning granularity with smaller partitions
Answer: B
Explanation: Parquet files are splittable by default. Maintaining the optimal file size (128 MB–1 GB) ensures maximum parallelism during Athena scans. Too-small files increase overhead; too-large files reduce parallelism. Combine with Snappy or ZSTD compression for best results.
Q43. The data engineering team has enabled Glue Job Bookmarks. What is the primary purpose of this feature?
A) Track Glue job execution history B) Track already-processed data to implement incremental processing C) Optimize Glue job costs D) Save data quality checkpoints
Answer: B
Explanation: Glue Job Bookmarks track which data was processed in previous runs. Subsequent runs process only newly added data, preventing duplicate processing. They use S3 file modification times and names to determine processing status. This enables efficient incremental ETL pipelines without reprocessing all data.
Q44. In a Kinesis Data Analytics (Apache Flink) application, you need to enrich streaming events using an external database as reference data. What is the recommended approach?
A) Load all reference data into Flink memory B) Use Flink Async I/O to asynchronously query the external database C) Send reference data as a Kinesis stream and join D) Enrich with a Lambda function and re-publish to Kinesis
Answer: B
Explanation: Flink Async I/O processes external database lookups (Redis, DynamoDB, etc.) asynchronously, minimizing processing latency. Synchronous lookups would block on external system responses and severely reduce throughput. Async I/O processes multiple outstanding requests concurrently. Consider local caching with RocksDB State Backend for further optimization.
Q45. A BI team wants to implement embedded analytics in a web application using QuickSight. External users (non-AWS users) must be able to view dashboards. What is the correct approach?
A) Create standard QuickSight user accounts for each external user B) Use the QuickSight embedded URL API with anonymous embedding or Reader sessions C) Share public dashboard links D) Export dashboard images to S3 and display on the web
Answer: B
Explanation: The QuickSight embedding API generates time-limited URLs for external users to view dashboards without a QuickSight account. Anonymous embedding (unauthenticated access) or Reader sessions (per-session pricing) are available. The embedded dashboard is rendered in an iframe within the web application.
Q46. When a Kinesis Data Firehose Lambda transformation function fails, how are failed records handled?
A) All records are deleted B) Failed records are stored in a separate S3 prefix (processing-failed prefix) C) Firehose automatically retries until success D) Failed records are returned to the source
Answer: B
Explanation: Records that fail Lambda transformation in Kinesis Data Firehose are written to the processing-failed S3 prefix. Successfully transformed records go to the configured destination. Failed records are preserved separately for later reprocessing or error analysis.
Q47. In a multi-AWS account environment, you want to build a central data lake in a central account and query business unit account data with Athena. How does Lake Formation support this?
A) Copy each account's S3 data to the central account B) Use Lake Formation cross-account data sharing C) Configure S3 cross-account replication D) Use AWS Organizations SCP to consolidate data access
Answer: B
Explanation: Lake Formation supports cross-account data sharing. Data owner accounts grant Lake Formation data permissions to IAM roles/users in the central account. Athena or Redshift Spectrum in the central account can query other accounts' data catalogs. This achieves centralized governance without data movement.
Q48. What is the primary benefit of using Apache Hudi on EMR?
A) Automatically converts Hive queries to Spark B) Supports UPSERT/DELETE and incremental processing on S3 C) Automatically scales the EMR cluster D) Automatically syncs data between HDFS and S3
Answer: B
Explanation: Apache Hudi enables UPSERT (insert/update), DELETE operations on data lake storage like S3, overcoming the immutability limitation of traditional data lakes. It provides Copy-on-Write and Merge-on-Read table types, and supports incremental queries to efficiently process only changed data.
Q49. What problem does AWS Glue Elastic Views solve?
A) Resolves out-of-memory issues in Glue ETL jobs B) Provides materialized views that replicate and combine data from multiple sources in near-real-time C) Fixes schema detection errors in Glue Crawlers D) Automatically caches Athena query results
Answer: B
Explanation: AWS Glue Elastic Views automatically replicates and combines data from source databases (DynamoDB, Aurora, RDS) to targets (OpenSearch, S3, Redshift) maintaining materialized views. A SQL-based view definition enables data integration without complex ETL pipelines.
Q50. What is the primary reason to apply S3 Intelligent-Tiering to a data lake?
A) Automatically encrypts all S3 operations B) Automatically monitors access patterns and moves data to the most cost-effective storage tier C) Automatically creates backups of S3 data D) Automates global data replication
Answer: B
Explanation: S3 Intelligent-Tiering monitors access frequency and automatically moves data: frequently accessed to Frequent Access tier, data not accessed for 30+ days to Infrequent Access, and 90+ days to Archive Instant Access. It is ideal for data lakes with unpredictable access patterns. Only a monitoring fee is added.
Q51. What is the primary purpose of the VACUUM command in Redshift?
A) Terminate unnecessary database connections B) Reclaim storage from deleted/updated rows and re-sort data by sort key order C) Clear the Redshift cluster cache D) Update table statistics
Answer: B
Explanation: Redshift VACUUM physically removes rows that were only soft-deleted/updated and re-sorts data by the sort key. Regular VACUUM reclaims storage and maintains query performance. ANALYZE updates table statistics. Redshift Serverless and recent versions support automatic VACUUM.
Q52. You extended Kinesis Data Streams retention to 7 days. You need to reprocess data starting from a specific timestamp. How do you do this?
A) Creating a new consumer group automatically starts from the beginning B) Use GetShardIterator API with AT_TIMESTAMP to start reading from a specific time C) Reprocess via S3 through Firehose D) Copy retention data to a new stream
Answer: B
Explanation: Setting ShardIteratorType to AT_TIMESTAMP in the Kinesis GetShardIterator API and specifying the desired timestamp lets you read data starting from that point. When using KCL, set the initial position to a timestamp.
Q53. What is the primary benefit of using the Glue Catalog as the shared metastore for Athena, Redshift Spectrum, and EMR?
A) Single metadata registry that shares schemas across multiple analytics engines, ensuring consistency B) Faster data processing speed C) Reduced S3 storage costs D) Automatic data quality validation
Answer: A
Explanation: The Glue Data Catalog is the central metadata store in AWS. Athena, Redshift Spectrum, and EMR all reference the same Glue Catalog, so table definitions, partition information, and schemas are managed in one place. Schema changes are automatically reflected across all analytics engines.
Q54. Data quality issues occur frequently in the data lake pipeline. Which AWS service automates quality checks in the data pipeline?
A) CloudWatch Alarms to monitor S3 file sizes B) AWS Glue Data Quality rules for automated validation C) Run manual data validation scripts with Lambda D) Send manual review notifications to the data team via SNS
Answer: B
Explanation: AWS Glue Data Quality defines quality rules (completeness, uniqueness, referential integrity, etc.) on datasets and automatically validates them during ETL jobs. It provides quality scores and rule pass/fail results. Integration with CloudWatch enables alerts when quality degrades.
Q55. What is the primary reason to choose EMR on EKS?
A) Always cheaper than EMR on EC2 B) Run Spark jobs on existing Kubernetes infrastructure, integrating container-based workloads C) Configure HDFS storage on the EKS cluster D) GPU-based deep learning only
Answer: B
Explanation: EMR on EKS runs Apache Spark on an existing Amazon EKS cluster. Organizations already using Kubernetes can consolidate data processing workloads without managing separate EMR clusters. Benefits include container isolation, resource sharing, and integration with existing Kubernetes tooling (Helm, Argo Workflows, etc.).
Q56. What is the benefit of enabling Redshift Concurrency Scaling?
A) Automatically adds cluster nodes for permanent expansion B) Automatically provisions additional cluster capacity during peak concurrency to maintain SLAs C) Automatically upgrades the Redshift cluster D) Automatically schedules overnight batch processing
Answer: B
Explanation: Redshift Concurrency Scaling automatically starts additional read clusters when concurrent queries saturate the main cluster. The first 24 hours per day are free; subsequent usage is billed per second. Users experience consistent, low-latency query performance without manual intervention.
Q57. When migrating from Aurora MySQL to Amazon Redshift using DMS, is the Schema Conversion Tool (SCT) required?
A) No, DMS automatically handles schema conversion B) Yes, Aurora MySQL and Redshift are different engines; SCT is needed for schema conversion C) No, Aurora and Redshift are both AWS services so conversion is unnecessary D) SCT is only required for on-premises databases
Answer: B
Explanation: DMS handles data movement; SCT handles schema (DDL, procedures, functions, etc.) conversion. A heterogeneous migration from Aurora MySQL (OLTP) to Redshift (OLAP) requires data type and table structure conversion. Run SCT first to generate Redshift-compatible DDL, then use DMS to replicate the data.
Q58. You want to share Athena query results with other teams and charge costs back by team. What is the correct approach?
A) Create a separate AWS account per team B) Use Athena Workgroups to isolate queries, track costs, and control data usage per team C) Use CloudWatch cost alarms to monitor budgets per team D) Use IAM tags to track query costs
Answer: B
Explanation: Athena Workgroups isolate queries by team or project and separately track query costs and data scanned per workgroup. You can set per-query data scan limits, specify result storage locations, and integrate with CloudWatch metrics. Combined with cost allocation tags, this enables team-level cost chargebacks.
Q59. What is the most appropriate use case for QuickSight ML Insights?
A) Directly train and deploy machine learning models B) Detect anomalies, generate forecasts, and auto-narratives from time-series data C) Display SageMaker model results in QuickSight D) Analyze A/B test results
Answer: B
Explanation: QuickSight ML Insights provides code-free Anomaly Detection, Forecasting, and Auto-narratives for time-series data. It internally uses Amazon Forecast and the Random Cut Forest algorithm. Business users can obtain ML-driven insights without data scientists.
Q60. What does the Lake Formation Blueprint feature do?
A) Provides data lake security policy templates B) Automates data ingestion workflows from common sources (RDS, DMS, etc.) to the S3 data lake C) Automatically generates Glue ETL job code D) Provides QuickSight dashboard templates
Answer: B
Explanation: Lake Formation Blueprints provide pre-configured workflows for common ingestion patterns (Database Snapshot, Incremental Database, Log File). They automatically create Glue crawlers and ETL jobs internally, reducing the complexity of data lake construction.
Q61. A data engineer needs to optimize a Glue ETL job converting S3 JSON data to Parquet. Currently processing as a single partition. How do you reduce processing time?
A) Switch the Glue job to Python Shell B) Use the groupFiles option to group small files and increase worker count C) Load data into Redshift first, then unload as Parquet D) Parallelize conversion with a Lambda function chain
Answer: B
Explanation: Glue ETL's groupFiles setting logically groups small files to optimize processing partition count. Increasing the number of workers (DPUs) enables greater parallelism. Spark internally processes data in parallel partitions, so sufficient DPU allocation is needed to fully utilize the parallelism.
Q62. How do you identify bottlenecks in long-running Redshift queries?
A) Check CPUUtilization in CloudWatch metrics B) Analyze STL_QUERY, STL_EXPLAIN, SVL_QUERY_SUMMARY system tables C) Search by query ID in Redshift audit logs D) Trace API calls with CloudTrail
Answer: B
Explanation: Redshift system tables enable query performance analysis. STL_QUERY contains completed query information, STL_EXPLAIN contains query plans, and SVL_QUERY_SUMMARY provides per-step execution statistics. Use the EXPLAIN command to view the execution plan and analyze data distribution, join strategies, and sort key effectiveness.
Q63. How do Buffering Hints (Buffer Size and Buffer Interval) work in Kinesis Data Firehose?
A) Both conditions must be met before data is delivered to S3 B) Data is delivered to S3 when either condition is met first C) Only Buffer Size is used as the delivery criterion D) Only Buffer Interval is used as the delivery criterion
Answer: B
Explanation: Kinesis Firehose delivers data to S3 when either the Buffer Size (MB) or Buffer Interval (seconds) threshold is reached first. For example, with a 5 MB buffer size and 60-second interval, data is flushed when either 5 MB accumulates or 60 seconds elapse — whichever comes first.
Q64. What information does enabling DynamoDB Streams capture?
A) All Read operations on the table B) Write change events (Put, Update, Delete) retained for 24 hours C) Only Scan operations D) GSI/LSI creation and deletion events
Answer: B
Explanation: DynamoDB Streams captures item-level changes (INSERT, MODIFY, REMOVE) on the table, retaining them for up to 24 hours. It can capture the before/after images of changed items. Combined with Lambda triggers, it enables event-driven architectures, real-time aggregations, and cross-system synchronization.
Q65. An enterprise needs to analyze data from various sources (RDS, DynamoDB, S3, Redshift) in a single platform. What is the most comprehensive solution?
A) Move all data to Redshift and analyze there B) AWS Glue Catalog + Athena Federated Query + Lake Formation integrated governance C) Use separate analytics tools for each source D) Consolidate all data into DynamoDB
Answer: B
Explanation: Using the AWS Glue Catalog as a central metadata store, Athena Federated Query for single-SQL access across heterogeneous sources, and Lake Formation for unified security and governance is the most comprehensive solution. Data remains in place; a unified access control policy is applied across all sources.
Study Resources
- AWS DAS-C01 Exam Guide
- AWS Data Analytics Documentation
- AWS Skill Builder DAS-C01 Official Learning Path
- AWS Big Data Whitepapers and Architecture Best Practices
This practice exam is created for study purposes. Actual exam questions may differ.