Replay

Database Migrations

The Replay app uses different database backends depending on the platform:

• Tauri (desktop): SQLite with Drizzle ORM
• Web: IndexedDB with the idb library

SQLite Migrations (Tauri)

SQLite schema is defined in src/db/schema/ using Drizzle ORM. Migrations are auto-generated.

To add a migration:

1. Update the schema in src/db/schema/ (e.g., history.schema.ts)
2. Generate the migration from the apps/replay-app directory:

   pnpm db:generate

3. This creates a new .sql file in apps/replay-app/src-tauri/migrations/ with a unique name
4. Migrations run automatically on app startup via the Rust backend
5. Alternatively, manually create a new migration file in apps/replay-app/src-tauri/migrations/:

# Format: YYYYMMDDHHMMSS_description.sql
src-tauri/migrations/20241224120000_add_user_settings.sql

-- Add new table
CREATE TABLE IF NOT EXISTS user_settings (
    id TEXT PRIMARY KEY NOT NULL,
    key TEXT NOT NULL UNIQUE,
    value TEXT NOT NULL
);

IndexedDB Migrations (Web)

IndexedDB uses version-based migrations.

To add a migration:

1. Increment the version constant in the storage class (e.g., HISTORY_DB_VERSION in HistoryIndexedDBStorage.ts)
2. Update the setupDatabase() method to handle both initial creation and upgrades:

const HISTORY_DB_VERSION = 2; // Increment for new migration

private static setupDatabase(db: IDBPDatabase<unknown>): void {
  // Initial setup (runs for new databases)
  if (!db.objectStoreNames.contains('history')) {
    const store = db.createObjectStore('history', { keyPath: 'id' });
    store.createIndex('by-date', 'date');
  }

  // Version 2: Add new index (runs on upgrade from v1)
  const tx = db.transaction('history', 'readwrite');
  const store = tx.objectStore('history');
  if (!store.indexNames.contains('by-new-field')) {
    store.createIndex('by-new-field', 'newField');
  }
}

Best practices:

• Always check if stores/indexes exist before creating
• Keep schema definitions in sync between SQLite and IndexedDB
• Test migrations with existing data before release