Models
In ORM-based systems, models define structured representations of persisted entities and their relationships.
They provide a shared contract between application logic and database structure, including relation mapping, defaults, and lifecycle hooks.
Model design decisions influence query efficiency, migration complexity, and long-term maintainability, so they should be reviewed together with schema and indexing strategy.
Why model design matters
Models are often where a software system quietly reveals what it thinks its domain actually is. If the model layer is shallow, inconsistent, or overloaded, the rest of the application usually inherits that confusion.
Well-designed models help by making identities, relationships, ownership boundaries, and state transitions explicit.
Common pressures
- Domain entities should be modeled around stable concepts, not short-lived UI needs.
- Relations and deletion behavior deserve careful thought because they shape data integrity and cleanup rules.
- Model convenience should not override indexing, query shape, and database behavior.
- In API-heavy systems, the model layer should stay distinct from transport-layer validation even when the tools make them look similar.