AWS Data Engineer (DEA-C01) pattern recognition

Streaming versus batch and service selection by constraint are the main recurring patterns

Data ingestion questions recur around the streaming-versus-batch decision: which Kinesis variant, MSK, or batch import pattern fits the described producer and consumer behavior. Transformation questions follow a service-selection-by-overhead pattern: Glue for managed ETL, EMR for cluster-level control, Lambda for lightweight event-driven transformation, with the scenario providing the overhead tolerance and scale signal. Storage placement questions test the decision between S3, DynamoDB, RDS, and Redshift based on access pattern and query structure. Security and governance questions test IAM policy scoping, Lake Formation permission configuration, and the boundary between data catalog access and underlying storage access. The question structures repeat across domains; the scenario context changes but the underlying decision logic stays the same.