在Core Data SQLite Persistent存储上使用Sqlite3 VACUUM命令

func vacuumDatabase(at storeURL: URL) throws {
    // 创建一个新的NSPersistentStoreCoordinator实例
    let coordinator = NSPersistentStoreCoordinator(managedObjectModel: managedObjectModel)

    // 创建一个新的数据库文件
    try coordinator.addPersistentStore(ofType: NSSQLiteStoreType, configurationName: nil, at: storeURL.appendingPathComponent("temp.sqlite"), options: nil)

    // 将现有的数据从旧的数据库文件复制到新的数据库文件中
    let moc = NSManagedObjectContext(concurrencyType: .mainQueueConcurrencyType)
    moc.persistentStoreCoordinator = coordinator
    let fetchRequest = NSFetchRequest<NSFetchRequestResult>(entityName: "YourEntityName")
    let results = try moc.fetch(fetchRequest)
    for result in results {
        moc.delete(result as! NSManagedObject)
    }
    try moc.save()

    // 使用Sqlite3 VACUUM命令优化新的数据库文件
    let sqliteConnection = try SQLiteConnection(storeURL.appendingPathComponent("temp.sqlite"))
    try sqliteConnection.execute("VACUUM")

    // 将现有的数据库文件替换为新的数据库文件
    try FileManager.default.removeItem(at: storeURL)
    try FileManager.default.moveItem(at: storeURL.appendingPathComponent("temp.sqlite"), to: storeURL)
}