sqflite common

The platform independent API of sqflite: DatabaseFactory, Database, Transaction, Batch, OpenDatabaseOptions, DatabaseException... It does not contain SQLite itself: an implementation package provides a DatabaseFactory.

Which package to use

An application depends on one (or several) of these packages. They all re-export this API, so an application does not need to depend on sqflite_common itself.

Depend on sqflite_common directly when your code must not depend on a platform: a package shared by a Flutter app and a Dart program, or code tested with sqflite_common_ffi. Import package:sqflite_common/sqlite_api.dart and take a DatabaseFactory as a parameter.

Usage in platform independent code

import 'package:sqflite_common/sqlite_api.dart';

/// Platform independent code: it only needs a [DatabaseFactory].
class NoteStore {
  NoteStore(this.factory, this.path);

  final DatabaseFactory factory;
  final String path;
  Future<Database>? _db;

  /// Opened once, on first use.
  Future<Database> get database => _db ??= factory.openDatabase(
    path,
    options: OpenDatabaseOptions(
      version: 1,
      onCreate: (db, version) async {
        await db.execute(
          'CREATE TABLE Note (id INTEGER PRIMARY KEY, content TEXT NOT NULL)',
        );
      },
    ),
  );

  Future<int> add(String content) async {
    var db = await database;
    return db.insert('Note', {'content': content});
  }

  Future<List<String>> list() async {
    var db = await database;
    var rows = await db.query('Note', orderBy: 'id');
    return rows.map((row) => row['content'] as String).toList();
  }

  Future<void> close() async {
    var db = await _db;
    _db = null;
    await db?.close();
  }
}

The caller gives the factory and the path:

• Flutter (sqflite): NoteStore(databaseFactory, join(await getDatabasesPath(), 'notes.db'))
• Dart VM, desktop, tests (sqflite_common_ffi): sqfliteFfiInit(); then NoteStore(databaseFactoryFfi, path) (inMemoryDatabasePath in tests)
• Web (sqflite_common_ffi_web): NoteStore(databaseFactoryFfiWeb, 'notes.db')

Global API

package:sqflite_common/sqflite.dart adds the global openDatabase(), deleteDatabase(), getDatabasesPath()... which use the global databaseFactory. The sqflite plugin sets it on Android, iOS and macOS; elsewhere, set it once in main() (databaseFactory = databaseFactoryFfi;). Using the global before it is set throws databaseFactory not initialized.

Rules

• Open a database once and keep it. With the default singleInstance: true, opening the same path again returns the same Database, including for inMemoryDatabasePath while it is open.
• onCreate, onUpgrade and onDowngrade run in a transaction; increment version for any schema change.
• In a transaction, use the Transaction object, not the Database (deadlock).
• Values are int, num, String, Uint8List or null; pass them as ? arguments, not in the SQL string.

See the sqflite README for a longer list of common pitfalls.

Documentation

• sqflite documentation (opening a database, SQL, transactions, batches)
• Iterate through results using a cursor
• SqfliteSqlCommand to prepare commands
• Logger
• API reference