Isar DB

Enhanced fork of Isar Database with continued maintenance and improvements

Quickstart • Documentation • Sample Apps • Support & Ideas • Pub.dev

About Isar DB #

Isar DB is an enhanced version of Isar Database with continued maintenance and improvements.

Maintainer: Usama Sarwar (GitHub)

Why Isar DB? #

• Active Maintenance: Regular updates and bug fixes
• Production Ready: Upgraded dependencies and modern Dart/Flutter support
• Enhanced Features: Additional improvements and optimizations
• Community Driven: Open to contributions and community feedback
• Future-Proof: Regular updates and compatibility with latest Flutter/Dart versions

Getting Started #

dependencies:
  isar_db: ^1.0.0
  isar_db_flutter_libs: ^1.0.0

This package maintains full compatibility with Isar API while providing:

• Updated Dependencies: Latest analyzer, build tools, and Flutter compatibility
• Bug Fixes: Resolved issues from the original project
• Performance Improvements: Enhanced performance and stability
• Production Ready: Thoroughly tested and ready for production use

Isar [ee-zahr]:

1. River in Bavaria, Germany.
2. Crazy fast NoSQL database that is a joy to use.

Isar DB vs Original Isar #

Here's what's included in each package:

What's New in Isar DB #

Isar DB includes several important improvements over the original:

• Updated Dependencies: Latest analyzer (7.7.1), build tools (2.5.4), and source_gen (2.0.0)
• Modern Flutter Support: Compatible with Flutter 3.35.7+ and Dart 3.9.2+
• Enhanced Build System: Improved code generation and build performance
• Bug Fixes: Resolved various issues from the original project
• Better Documentation: Updated examples and migration guides
• Production Testing: 583 tests passing, fully production-ready

Features #

• 💙 Made for Flutter. Easy to use, no config, no boilerplate
• 🚀 Highly scalable The sky is the limit (pun intended)
• 🍭 Feature rich. Composite & multi-entry indexes, query modifiers, JSON support etc.
• ⏱ Asynchronous. Parallel query operations & multi-isolate support by default
• 🦄 Open source. Everything is open source and free forever!

Isar database can do much more (and we are just getting started)

• 🕵️ Full-text search. Make searching fast and fun
• 📱 Multiplatform. iOS, Android, Desktop
• 🧪 ACID semantics. Rely on database consistency
• 💃 Static typing. Compile-time checked and autocompleted queries
• ✨ Beautiful documentation. Readable, easy to understand and ever-improving

If you want to say thank you, star us on GitHub and like us on pub.flutter-io.cn 🙌💙

Quickstart #

Holy smokes you're here! Let's get started on using the coolest Flutter database out there...

1. Add to pubspec.yaml #

dependencies:
  isar_db: ^1.0.0
  isar_db_flutter_libs: ^1.0.0 # contains Isar Core

dev_dependencies:
  build_runner: any

2. Annotate a Collection #

part 'email.g.dart';

@collection
class Email {
  Email({
    this.id,
    this.title,
    this.recipients,
    this.status = Status.pending,
  });

  final int id;

  @Index(type: IndexType.value)
  final String? title;

  final List<Recipient>? recipients;

  final Status status;
}

@embedded
class Recipient {
  String? name;

  String? address;
}

enum Status {
  draft,
  pending,
  sent,
}

3. Open a database instance #

final dir = await getApplicationDocumentsDirectory();
final isar = await Isar.openAsync(
  schemas: [EmailSchema],
  directory: dir.path,
);

4. Query the database #

final emails = isar.emails.where()
  .titleContains('awesome', caseSensitive: false)
  .sortByStatusDesc()
  .limit(10)
  .findAll();

Isar Database Inspector #

The Isar Inspector allows you to inspect the Isar instances & collections of your app in real-time. You can execute queries, edit properties, switch between instances and sort the data.

To launch the inspector, just run your Isar app in debug mode and open the Inspector link in the logs.

CRUD operations #

All basic crud operations are available via the IsarCollection.

final newEmail = Email()..title = 'Amazing new database';

await isar.writeAsync(() {
  isar.emails.put(newEmail); // insert & update
});

final existingEmail = isar.emails.get(newEmail.id!); // get

await isar.writeAsync(() {
  isar.emails.delete(existingEmail.id!); // delete
});

Database Queries #

Isar database has a powerful query language that allows you to make use of your indexes, filter distinct objects, use complex and(), or() and .xor() groups, query links and sort the results.

final importantEmails = isar.emails
  .where()
  .titleStartsWith('Important') // use index
  .limit(10)
  .findAll()

final specificEmails = isar.emails
  .filter()
  .recipient((q) => q.nameEqualTo('David')) // query embedded objects
  .or()
  .titleMatches('*university*', caseSensitive: false) // title containing 'university' (case insensitive)
  .findAll()

Database Watchers #

With Isar database, you can watch collections, objects, or queries. A watcher is notified after a transaction commits successfully and the target changes. Watchers can be lazy and not reload the data or they can be non-lazy and fetch new results in the background.

Stream<void> collectionStream = isar.emails.watchLazy();

Stream<List<Post>> queryStream = importantEmails.watch();

queryStream.listen((newResult) {
  // do UI updates
})

Benchmarks #

Benchmarks only give a rough idea of the performance of a database but as you can see, Isar NoSQL database is quite fast 😇

If you are interested in more benchmarks or want to check how Isar performs on your device you can run the benchmarks yourself.

Unit tests #

If you want to use Isar database in unit tests or Dart code, call await Isar.initializeIsarCore(download: true) before using Isar in your tests.

Isar NoSQL database will automatically download the correct binary for your platform. You can also pass a libraries map to adjust the download location for each platform.

Make sure to use flutter test -j 1 to avoid tests running in parallel. This would break the automatic download.

Contributors ✨ #

Big thanks go to these wonderful people:

Usama Sarwar	Alexis	Burak	Carlo Loguercio	Frostedfox	Hafeez Rana	Hamed H.	JT
Jack Rivers	Joachim Nohl	Johnson	LaLucid	Lety	Michael	Moseco
Nelson Mutane	Oscar Palomar	Peyman	Simon Choi	Ura	blendthink	mnkeis
nobkd

License #

Copyright 2025 Usama Sarwar

Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at

   http://www.apache.org/licenses/LICENSE-2.0

Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.