Expo and SQLite: Local Data Storage Solution

In the world of mobile app development, data storage is of vital importance. When it is necessary to save user data, in-app settings, or other information, a robust data storage mechanism is required. In this article, we will examine local data storage methods using Expo and SQLite. First, we need to understand what Expo is and how it integrates with SQLite.

What is Expo?

Expo is a platform used for developing React Native applications. It provides developers with a fast prototyping process and supports them with many ready-made components and tools. In addition, the Expo SDK comes with various built-in tools such as the SQLite library. Thus, application developers can quickly create and test their applications.

Integration with SQLite

SQLite is a lightweight database engine and is especially ideal for mobile applications. Storing local data using SQLite with Expo is an effective way to store user data on the device. Thanks to the SQLite support offered by the Expo SDK, database operations can be carried out easily.

Installation

First, you need to install the SQLite library in your Expo project to be able to use it:

expo install expo-sqlite

Creating a Database and Adding Data

It is quite easy to create a database using SQLite. In the example below, we will create a database and add data:

import * as SQLite from 'expo-sqlite';

const db = SQLite.openDatabase('myDatabase.db');

db.transaction(tx => {
  tx.executeSql(
    'CREATE TABLE IF NOT EXISTS items (id INTEGER PRIMARY KEY NOT NULL, name TEXT);'
  );
  tx.executeSql(
    'INSERT INTO items (name) VALUES (?);', ['Example Item']
  );
});

Reading Data

You can use a similar SQL command to read the data you have added:

db.transaction(tx => {
  tx.executeSql(
    'SELECT * FROM items;',
    [],
    (_, { rows }) => console.log(JSON.stringify(rows)),
    (tx, error) => console.error(error)
  );
});

Conclusion

The combination of Expo and SQLite offers a powerful method for storing data in mobile applications. While keeping user data on the device, you can also increase the performance of your application. In this article, we explained step by step how to create a database, add data, and read data with SQLite. By applying these approaches in your own projects, you can improve the user experience.