drift/docs/content/en/docs/platforms.md

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Supported platforms All platforms supported by moor, and how to use them

Being built ontop of the sqlite3 database, moor can run on almost every Dart platform. Since the initial release of moor, the Dart and Flutter ecosystems have changed a lot. For instance, dart:ffi wasn't a thing when moor first came out, and now it's the basis for moor's most popular implemention. To clear confusion about different moor packages and when to use them, this document lists all supported platforms and how to use moor when building apps for them.

To achive platform independence, moor separates its core apis from a platform-specific database implementation. The core apis are pure-Dart and run on all Dart platforms, even outside of Flutter. When writing moor apps, prefer to mainly use the apis in package:moor/moor.dart as they are guaranteed to work across all platforms. Depending on your platform, you can choose a different QueryExecutor.

Mobile (Android and iOS)

There are two moor implementations for mobile that you can use:

using moor_flutter

The original moor_flutter package uses sqflite and only works on Android and iOS. For new projects, we generally recommend the newer ffi-based implementation, but moor_flutter is still maintained and suppported.

using moor/ffi

The new package:moor/ffi.dart implementation uses dart:ffi to bind to sqlite3 on Android and iOS. This is the recommended approach for newer projects as described in the [getting started]({{<relref "Getting started/_index.md">}}) guide.

To ensure that your app ships with the latest sqlite3 version, also add a dependency to the sqlite3_flutter_libs package when using package:moor/ffi.dart!

Web

Main article: [Web]({{<relref "Other engines/web.md">}})

For apps that run on the web, you can use moor's experimental web implementation, located in package:moor/moor_web.dart. As it binds to sql.js, special setup is required. Please read the main article for details.

Desktop

Moor also supports all major Desktop operating systems where Dart runs on by using the VmDatabase from package:moor/ffi.dart. Depending on your operating system, further setup might be required:

Windows

On Windows, you can download sqlite and extract sqlite3.dll into a folder that's in your PATH environment variable to use moor.

You can also ship a custom sqlite3.dll along with your app. See the section below for details.

Linux

On most distributions, libsqlite3.so is installed already. If you only need to use moor for development, you can just install the sqlite3 libraries. On Ubuntu and other Debian-based distros, you can install the libsqlite3-dev package for this. Virtually every other distribution will also have a prebuilt package for sqlite.

You can also ship a custom libsqlite3.so along with your app. See the section below for details.

macOS

This one is easy! Just use the VmDatabase from package:moor/ffi.dart. No further setup is necessary.

If you need a custom sqlite3 library, or want to make sure that your app will always use a specific sqlite3 version, you can also ship that version with your app.

Bundling sqlite with your app

If you don't want to use the sqlite3 version from the operating system (or if it's not available), you can also ship sqlite3 with your app. The best way to do that depends on how you ship your app. Here, we assume that you can install the dynamic library for sqlite next to your application executable.

This example shows how to do that on Linux, by using a custom sqlite3.so that we assume lives next to your application:

import 'dart:ffi';
import 'dart:io';
import 'package:sqlite3/sqlite3.dart';
import 'package:sqlite3/open.dart';

void main() {
  open.overrideFor(OperatingSystem.linux, _openOnLinux);

  // After setting all the overrides, you can use moor!
}

DynamicLibrary _openOnLinux() {
  final script = File(Platform.script.toFilePath());
  final libraryNextToScript = File('${script.path}/sqlite3.so');
  return DynamicLibrary.open(libraryNextToScript.path);
}
// _openOnWindows could be implemented similarly by opening `sqlite3.dll`

Be sure to use moor after you set the platform-specific overrides.