Swiftdata

This covers the full SwiftData lifecycle: defining @Model classes with attributes and relationships, querying with @Query and #Predicate, managing concurrency with @ModelActor, and planning schema migrations with VersionedSchema. You'll reach for it when setting up persistence in a new iOS app, migrating from Core Data, or debugging why your relationships cascade incorrectly. The predicate syntax takes getting used to,it's expressive but limited compared to arbitrary Swift,and the migration examples show both lightweight and custom stages, which is helpful since Apple's docs gloss over the custom case. Solid reference when you're past the hello-world phase and need to handle real schema evolution or background imports.