🗄️ SwiftDataBeginneriOS 17+ · macOS 14+

@Model & ModelContainer

Turn a Swift class into a persistent model and wire the storage into your app with one modifier.

The @Model macro makes a class persistable. Stored properties become columns; relationships to other models are inferred automatically.

Attach .modelContainer(for:) at the app level, then read the context with @Environment(\.modelContext) to insert and delete objects.

swiftdata-model.swift

1import SwiftData
2import SwiftUI
3
4@Model
5final class Habit {
6    var name: String
7    var createdAt: Date
8    @Relationship(deleteRule: .cascade) var entries: [HabitEntry] = []
9
10    init(name: String, createdAt: Date = .now) {
11        self.name = name
12        self.createdAt = createdAt
13    }
14}
15
16@Model
17final class HabitEntry {
18    var date: Date
19    init(date: Date = .now) { self.date = date }
20}
21
22@main
23struct HabitsApp: App {
24    var body: some Scene {
25        WindowGroup { ContentView() }
26            .modelContainer(for: Habit.self)
27    }
28}

Common pitfalls

@Model only works on classes, not structs.
Changing a model after release needs a migration plan (VersionedSchema + SchemaMigrationPlan) for non-trivial changes.

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Common pitfalls

Still unclear? Ask BeeAI about @Model & ModelContainer.

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