Choosing the Right Offline Database for Your Flutter App

Overview of Each Database

In today’s always-connected world, there are still many use cases for storing data offline, especially in mobile development. When it comes to choosing an offline database for your Flutter app, there are several options to consider. Here are five popular offline databases for Flutter:

• Hive: A key-value database written in pure Dart, with no native dependencies.
• Sembast: A NoSQL database that uses a text document where each entry is a JSON object.
• Sqflite: A SQL database that provides the ability to write raw SQL commands.
• Isar: A feature-rich offline database with powerful queries, filters, and sort functionalities.
• ObjectBox: A NoSQL database written in pure Dart, with support for type annotations and code generation.

Setup and Syntax

Setting up each database is relatively straightforward. However, the syntax and ease of use vary between them.

// Hive example
import 'package:hive/hive.dart';

Future main() async {
  var box = await Hive.openBox('myBox');
  box.put('name', 'John Doe');
  print(box.get('name'));
}

// Sembast example
import 'package:sembast/sembast.dart';

Future main() async {
  var db = await databaseFactoryIo.openDatabase('myDB.db');
  var store = StoreRef.main();
  await store.add(db, {'name': 'John Doe'});
  var records = await store.find(db);
  print(records.first['name']);
}

Benchmarking Results

To compare the performance of each database, we ran benchmarking tests on both Android and iOS physical devices. The tests included writing, reading, and deleting 1,000 individual items, as well as using optimized methods to perform these operations.

The results showed that:

• Isar was the fastest for write operations on iOS, while Hive was the fastest on Android.
• Hive was the fastest for read operations on both iOS and Android.
• Isar was the fastest for delete operations on both iOS and Android.

Conclusion

Choosing the right offline database for your Flutter app depends on your specific needs and preferences. If you prioritize ease of use and simplicity, Hive or Sembast may be a good choice. If you need more features and flexibility, Isar or ObjectBox may be a better fit. Ultimately, the best database for your app will depend on your specific requirements and performance needs.

By considering the strengths and weaknesses of each database, you can make an informed decision and choose the best offline database for your Flutter app.