Isar Database

🚧 Very unstable and not ready for serious usage 🚧

Quickstart • Documentation • Examples • Support & Ideas • Pub.dev

Isar [ee-zahr]:

1. River in Bavaria, Germany.
2. Database that will make your life easier.

Features

• ⚡️ Launch your app instantly no matter how much data you have
• 📈 Highly scalable from hundreds to tens of thousands of records
• 😎 Lazy loaded. Only load data when you need it
• 🔎 Full text search. Make searching fast and fun
• 📱 Multiplatform. iOS, Android, Desktop and the web (soon™)
• 💙 Made for Flutter. Easily use it in your Flutter app
• 🧪 ACID semantics. Rely on consistency
• ⏱ Asynchronous. Parallel query operations & multi-isolate support
• ⚠️ Static typing with compile time checked and autocompleted queries

Add to pubspec.yaml

dependencies:
  isar: any
  isar_flutter: any # contains the binaries

dev_dependencies:
  isar_generator: any
  build_runnder: any

Schema definition

@Collection()
class Post with IsarObject {

  @ObjectId() // implicit unique index
  String uuid;
  @Index(stringType: StringIndexType.words, caseSensitive: false) // Search index
  String title;
  List comments
}

CRUD operations

All basic crud operations are available via the IsarCollection.

final newPost = Post()
  ..id = uuid()
  ..title = 'Amazing new database'
  ..comments = ['First'];

await isar.writeTxn((isar) {
  await isar.posts.put(newPost); // insert
});
final existingPost = await isar.get(newPost.id); // get
await isar.writeTxn((isar) {
  await isar.posts.delete(existingPost.id); // delete
});

Queries

Isar has a powerful query language that allows you to make use of your indexes, filter distinct objects, use complex

and()

or()

final isar = await openIsar();

final databasePosts = isar.posts
  .where()
  .titleWordBeginsWith('dAtAb') // use search index
  .limit(10)
  .findAll()
final postsWithFirstCommentOrTitle = isar.posts
  .where()
  .sortedById() // use implicit ObjectId index
  .filter()
  .commentsAnyEqualTo('first', caseSensitive: false)
  .or()
  .titleEqualTo('first')
  .findAll();

Watchers

With Isar you can watch Collections, Objects or Queries. A watcher is notified after a transactions commits succesfully and the target actually changes. Watchers can be lazy and not reload the data or they can be non-lazy and fetch the new results in background.

Stream collectionStream = isar.posts.watch(lazy: true);

Stream> queryStream = databasePosts.watch(lazy: false);
queryStream.listen((newResult) {
  // do UI updates
})

Licence

Copyright 2021 Simon Leier

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.