What is the typical sequence for converting a conceptual model to a physical schema?

• A. Identify entities/relationships, define keys and constraints, map to tables/columns, decide data types, apply normalization, implement in DB
• B. Define data types first, then identify entities
• C. Implement in DB, then map to tables
• D. Create physical tables before defining relationships

Answer: (C)

This question is about the order in which you move from a conceptual model to a physical schema. The best fit is to implement in the database first and then map to tables. Doing the implementation in the DB first lets you work with the actual database environment, which reveals real constraints, supported data types, storage considerations, and engine-specific features. That concrete foundation then guides how you translate entities, relationships, keys, and constraints into the final table structures, columns, and relationships. It centers the design process on the database’s realities, ensuring the physical design aligns with how the system will actually run.

Other approaches jump ahead to data types or structure without first grappling with the database’s capabilities, or they describe creating tables and relationships before engaging with the implementation context. That can lead to mismatches between the abstract model and what the database supports or how it performs.