swiftdata-inheritance

Implement SwiftData class inheritance by applying the `@Model` macro to both base and subclass definitions, establishing hierarchical data structures and polymorphic relationships for iOS and macOS development.

Query specific subclasses from a SwiftData base class by constructing proper predicates for type filtering, fetching data from the base class to isolate distinct model variants like `MeetingEvent` or `TaskEvent`.

Use SwiftData class inheritance when modeling hierarchical data requiring polymorphic relationships and type-based querying across model variants, whereas enums or protocols suit flatter data structures without complex querying needs.

SwiftData supports polymorphic relationships through class inheritance, allowing you to define a common base class like `CalendarEvent` and link various user-defined event types such as `ReminderEvent` efficiently.

Common pitfalls when querying SwiftData model variants include incorrect predicate construction for type filtering and failing to apply the `@Model` macro to subclass definitions, which disrupts type-based querying.