Using SQLite in Node.js with Real-World Examples
SQLite is a popular open-source, serverless, and self-contained SQL database engine that is used in a wide range of applications, including mobile apps, desktop software, and web applications. In this blog post, we will explore how to use SQLite in Node.js and provide real-world examples of its applications.
What is SQLite?
SQLite is a C library that provides a lightweight disk-based database that doesn’t require a separate server process and allows direct interaction with the database files. It is often considered a zero-configuration, serverless, and self-contained database engine. Here are some key features:
- Self-contained: The entire SQLite database is a single ordinary file on disk.
- Zero-configuration: No need to set up a separate server or install complex software.
- Transactional: Supports ACID (Atomicity, Consistency, Isolation, Durability) transactions.
- Highly reliable: Widely used in production for mobile and desktop applications.
- Cross-platform: Runs on various operating systems.
Using SQLite in Node.js
To use SQLite in Node.js, you’ll need to install the sqlite3 package. You can do this by running:
npm install sqlite3
Now, let’s dive into some real-world examples of how to use SQLite in Node.js.
Example 1: Creating a SQLite Database
In this example, we will create a new SQLite database and define a table.
const sqlite3 = require('sqlite3').verbose();
const db = new sqlite3.Database('mydb.db');
db.serialize(() => {
db.run('CREATE TABLE users (id INT, name TEXT)');
});
db.close();
Example 2: Inserting Data
Now, let’s insert data into the database:
const sqlite3 = require('sqlite3').verbose();
const db = new sqlite3.Database('mydb.db');
const statement = db.prepare('INSERT INTO users VALUES (?, ?)');
statement.run(1, 'John Doe');
statement.run(2, 'Jane Smith');
statement.finalize();
db.close();
Example 3: Querying Data
You can query data from the database using SQL statements:
const sqlite3 = require('sqlite3').verbose();
const db = new sqlite3.Database('mydb.db');
db.each('SELECT id, name FROM users', (err, row) => {
console.log(row.id, row.name);
});
db.close();
Example 4: Updating and Deleting Data
Updating and deleting data is also straightforward:
const sqlite3 = require('sqlite3').verbose();
const db = new sqlite3.Database('mydb.db');
// Update
db.run('UPDATE users SET name = "Updated Name" WHERE id = 1');
// Delete
db.run('DELETE FROM users WHERE id = 2');
db.close();
Example 5: Error Handling
SQLite operations may encounter errors. You should include proper error handling in your code:
const sqlite3 = require('sqlite3').verbose();
const db = new sqlite3.Database('mydb.db');
db.run('sect from users', (err) => {
if (err) {
console.error('Error:', err.message);
}
});
db.close();
Conclusion
SQLite is a versatile and lightweight database engine that can be a great choice for many Node.js applications. In this blog post, we’ve covered the basics of using SQLite in Node.js with real-world examples. Feel free to explore more advanced features and libraries available for SQLite to build robust and efficient applications.
Happy coding with SQLite in Node.js!