SQLiteData Migration

Complete migration guide from Apple's SwiftData to Point-Free's SQLiteData, covering when to migrate, pattern equivalents, and gradual migration strategies.

Overview

Guide for migrating from SwiftData to SQLiteData, including decision framework, code pattern conversions, CloudKit sharing (SwiftData can't), and performance considerations.

When to Migrate

Migrate to SQLiteData When

• ✅ Need CloudKit record sharing (SwiftData only syncs, no sharing)
• ✅ Have 50k+ records with performance concerns
• ✅ Want value types (structs) over reference types (classes)
• ✅ Need more control over SQL queries
• ✅ Prefer explicit over magic behavior

Stay with SwiftData When

• Simple CRUD with native Apple integration
• Already working well with @Model classes
• Don't need CloudKit record sharing
• Team prefers Apple-native solutions

Pattern Equivalents

Model Definition

SwiftData

@Model
class Task {
    var id: UUID
    var title: String
    var isComplete: Bool

    init(title: String) {
        self.id = UUID()
        self.title = title
        self.isComplete = false
    }
}

SQLiteData

@Table
struct Task: Identifiable, Sendable {
    @Attribute(.primaryKey)
    var id: UUID
    var title: String
    var isComplete: Bool
}

Queries

SwiftData

@Query(filter: #Predicate { !$0.isComplete })
var incompleteTasks: [Task]

SQLiteData

@FetchAll(Task.where { !$0.isComplete })
var incompleteTasks: [Task]

Relationships

SwiftData

@Model
class Task {
    @Relationship(deleteRule: .cascade)
    var subtasks: [Subtask]
}

SQLiteData

@Table
struct Task: Identifiable, Sendable {
    var id: UUID
    // Relationships via foreign keys
}

@Table
struct Subtask: Identifiable, Sendable {
    var id: UUID
    var taskId: UUID  // Foreign key
}

Migration Strategy

Gradual Migration

1. Add SQLiteData alongside SwiftData
2. Migrate one model at a time
3. Keep both running during transition
4. Remove SwiftData when complete

Data Migration

func migrateToSQLiteData() async throws {
    // Fetch from SwiftData
    let tasks = try modelContext.fetch(FetchDescriptor<Task>())

    // Write to SQLiteData
    try await database.write { db in
        for task in tasks {
            try SQLiteTask.insert {
                SQLiteTask(
                    id: task.id,
                    title: task.title,
                    isComplete: task.isComplete
                )
            }.execute(db)
        }
    }
}

CloudKit Sharing

SwiftData limitation: Can only sync, cannot share records

SQLiteData advantage:

// Full CloudKit sharing support
let share = CKShare(rootRecord: record)
try await database.share(record, with: share)

Performance Comparison

Operation	SwiftData	SQLiteData
Insert 50k	~60s	~30s
Fetch 10k	~2s	~0.5s
Complex query	Core Data layer	Direct SQL

Related Resources

• sqlitedata — SQLiteData patterns
• swiftdata — SwiftData patterns
• database-migration — Safe schema evolution