Persistence

Comprehensive database patterns for safe schema evolution and choosing the right persistence framework for your needs.

Skills

• Database Migration – Safe schema evolution for SQLite/GRDB/SwiftData, prevents data loss

  • "I need to add a column to my live app without losing user data. How do I migrate safely?"
  • "I'm getting 'cannot add NOT NULL column' errors. What does this mean?"

• SQLiteData – Point-Free's SQLiteData patterns, batch performance, and CloudKit sync

  • "I'm building a task app with type-safe queries. How do I set up @Table models and filter by priority?"
  • "I'm importing 50,000 notes from an API. How do I batch insert efficiently without blocking the UI?"

• SQLiteData Migration – Migration guide from SwiftData to SQLiteData

  • "SwiftData's CloudKit sync is causing conflicts. Should I migrate to SQLiteData?"
  • "How do I convert my @Model classes to @Table? What's the equivalent of @Relationship?"

• GRDB – Raw SQL queries, ValueObservation, and DatabaseMigrator patterns

  • "I need to query messages with their authors and reaction counts in one query. How do I write the JOIN?"
  • "I want to observe notes with a specific tag and update the UI whenever they change."

• SwiftData – iOS 26+ features, @Model, @Query patterns, and Swift 6 concurrency

  • "I have a notes app with folders. How do I filter and sort with @Query?"
  • "When a user deletes a task list, all tasks should auto-delete too. How do I set up cascading deletes?"

• Core Data – Stack setup, concurrency patterns, relationship modeling for iOS 16 and earlier

  • "I'm targeting iOS 16. How do I set up Core Data with CloudKit sync?"
  • "I'm getting thread-confinement errors. How do I use background contexts correctly?"

• Cloud Sync – CloudKit vs iCloud Drive, offline-first patterns, conflict resolution

  • "Should I use CloudKit or iCloud Drive for my app's data?"
  • "How do I handle sync conflicts when users edit on multiple devices?"