1. Database Integration in Node.js
Database integration is a crucial part of building dynamic and data-driven applications. Node.js provides several tools and libraries to connect with databases, perform CRUD operations, and manage data efficiently.
2. Types of Databases
SQL Databases: Structured databases that use tables for data storage. Examples:
NoSQL Databases: Flexible, schema-less databases for unstructured data. Examples:
3.Steps to Integrate a Database in Node.js
1. Install Database Driver or ORM
Use npm to install the required library for the database you want to use.
npm install mongoose # For MongoDB
npm install mysql # For MySQL
2. Connect to the Database
Establish a connection using the library's API.
3. Perform Operations
Execute queries, insert data, or retrieve results from the database.
4. Close Connection
Always close the connection when it's no longer needed to free resources.
Example 1: MongoDB Integration
1. Install Dependencies
npm install mongoose
2. Example Code
const mongoose = require('mongoose');
// Connect to MongoDB
mongoose.connect('mongodb://localhost:27017/mydatabase', {
useNewUrlParser: true,
useUnifiedTopology: true,
});
const db = mongoose.connection;
db.on('error', console.error.bind(console, 'Connection error:'));
db.once('open', () => {
console.log('Connected to MongoDB');
});
// Define a Schema
const userSchema = new mongoose.Schema({
name: String,
email: String,
age: Number,
});
// Create a Model
const User = mongoose.model('User', userSchema);
// Insert Data
const newUser = new User({ name: 'John', email: 'john@example.com', age: 25 });
newUser.save((err) => {
if (err) return console.error(err);
console.log('User saved to database');
});
Example 2: MySQL Integration
MySQL is a widely used SQL database. Below is an example of integrating MySQL with Node.js.
1. Install Dependencies
npm install mysql
2. Example Code
const mysql = require('mysql');
// Create a MySQL connection
const connection = mysql.createConnection({
host: 'localhost',
user: 'root',
password: 'password',
database: 'mydatabase',
});
// Connect to MySQL
connection.connect((err) => {
if (err) throw err;
console.log('Connected to MySQL');
});
// Query Data
connection.query('SELECT * FROM users', (error, results) => {
if (error) throw error;
console.log('Data from users table:', results);
});
// Close Connection
connection.end();
Best Practices for Database Integration
1. Use Environment Variables: Store sensitive information (e.g., database credentials) in environment files.
DB_HOST=localhost
DB_USER=root
DB_PASSWORD=password
DB_NAME=mydatabase