31.1. Data Persistence with SQLite in Flutter: Introduction to SQLite

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SQLite is a C language library that provides a lightweight disk-based database that does not require a separate server process and allows access to the database through local variables. SQLite is a popular component on mobile operating systems and is widely used on Android and iOS, making it an excellent choice for data persistence in Flutter as well.

Introduction to SQLite

SQLite is a relational database management system (RDBMS) contained in a C library. In contrast to many other database systems, SQLite is not a client-server system. This means that, unlike MySQL, PostgreSQL and SQL Server, SQLite does not have a separate server process. SQLite reads and writes directly to disk files.

SQLite is a perfect choice for applications that need a lightweight database without the need to install a separate database management system (DBMS). It is easy to use and requires little or no configuration. Furthermore, SQLite supports all relational database operations such as transactions, triggers and full SQL queries.

Data Persistence with SQLite in Flutter

Flutter is a mobile application development SDK that offers a variety of tools and libraries to facilitate application development. It offers a library called "sqflite" to integrate SQLite into your Flutter application.

sqflite is a Flutter plugin that allows you to perform SQLite database operations such as CRUD (Create, Read, Update, Delete), queries and other database operations. It provides a high-level abstract interface for communicating with an SQLite database.

How to use SQLite in Flutter

To start using SQLite in Flutter, you need to add the sqflite dependency to your pubspec.yaml file:

dependencies:
  flutter:
    sdk: flutter
  sqflite: any

After that you can import the sqflite into your Dart file:

import 'package:sqflite/sqflite.dart';

To create an SQLite database, you can use the openDatabase method, which returns a Database object. You can use this object to perform database operations.

Here is an example of how to create a database:

final Future database = openDatabase(
  join(await getDatabasesPath(), 'my_database.db'),
);

This code creates a database called 'my_database.db'. If the database already exists, Flutter will open the existing database. If not, Flutter will create a new one.

To create a table in your database, you can use the onCreate method, which is called when the database is first created.

final Future database = openDatabase(
  join(await getDatabasesPath(), 'my_database.db'),
  onCreate: (db, version) {
    return db.execute(
      "CREATE TABLE my_table(id INTEGER PRIMARY KEY, name TEXT)",
    );
  },
  version: 1,
);

This code creates a table called 'my_table' with two columns: 'id' and 'name'.

With SQLite and Flutter, you can easily build applications with data persistence, making your applications more robust and efficient. With the sqflite library, you can perform all database operations required by your application, from creating the database to performing CRUD operations.

In summary, SQLite is an excellent choice for data persistence in Flutter applications due to its simplicity, efficiency and ease of use. With SQLite, you can build more robust and efficient Flutter applications that can handle a large amount of data efficiently.

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25631.2. Data persistence with SQLite in Flutter: Configuration and installation of the SQLite plugin