Database Modernization And Migration Strategy — AWS Solutions Architect Pro (SAP-C02)
Access Pattern Selects the Database, Not Familiarity with RDS
High-speed ingestion of timestamped IoT sensor data with time-range queries maps to Amazon Timestream. Highly connected data requiring traversal across many entity relationships maps to Neptune. Single-digit millisecond reads at any scale with a flexible schema and no complex joins maps to DynamoDB. Sub-millisecond in-memory access to a hot working set maps to ElastiCache. Multi-table relational data with complex queries and ACID transactions maps to Aurora. SAP-C02 presents these as workload and access pattern descriptions, not as service names. Knowing this mapping directly is faster under time pressure than reasoning from first principles; the workload description contains the answer when read against the access-pattern-to-service correspondence.
What This Pattern Tests
The exam tests database migration approach selection. Homogeneous migration (Oracle to Oracle on RDS, PostgreSQL to Aurora PostgreSQL) uses DMS with direct replication — minimal schema changes. Heterogeneous migration (Oracle to Aurora PostgreSQL, SQL Server to MySQL) requires AWS Schema Conversion Tool (SCT) to convert schema and stored procedures first, then DMS for data. Modernization to DynamoDB or DocumentDB requires application-level changes because the data model changes fundamentally. The trap is assuming DMS handles schema conversion (it migrates data, not schema) or that NoSQL migration is just a data copy (the application queries must change).
Decision Axis
Schema compatibility determines approach: same engine = DMS, different engine = SCT + DMS, different model (relational to NoSQL) = application rewrite.
Associated Traps
More Top Traps on This Exam
Decision Rules
Whether the workload's dominant access pattern—multi-table relational JOINs—maps to a managed relational engine (Aurora) or a purpose-built NoSQL engine (DynamoDB), where the JOIN requirement is a hard disqualifier for DynamoDB regardless of its operational, scalability, or modernization appeal.
Domain Coverage
Difficulty Breakdown