# CRUD Application with Node.js and MySQL

##  Objective
This project is a **CRUD (Create, Read, Update, Delete)** application built with **Node.js (Express)** and connected to a **MySQL database**.  
It demonstrates CRUD operations for the **Users** entity and can be extended to support more entities (e.g., Courses, Orders, etc.).

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##  Technologies Used
- **Node.js** – Backend runtime  
- **Express.js** – REST API framework  
- **MySQL** – Relational database  
- **mysql2** – Node.js MySQL driver  
- **Nodemon** – Development server auto-reload  
- **Postman** – API testing  

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##  Project Setup

### 1️⃣ Clone the Repository
```bash
git clone <your-repo-link>
cd crud-app-node-mysql

2️⃣ Install Dependencies

npm install

3️⃣ Configure Environment Variables

Create a .env file in the root directory:

DB_HOST=localhost
DB_USER=root
DB_PASSWORD=<your_mysql_password>
DB_NAME=crud_db
PORT=4000

4️⃣ Setup Database

Start MySQL and run the following commands:

CREATE DATABASE IF NOT EXISTS crud_db;
USE crud_db;

CREATE TABLE IF NOT EXISTS users (
  id INT AUTO_INCREMENT PRIMARY KEY,
  name VARCHAR(255) NOT NULL,
  email VARCHAR(255) NOT NULL,
  age INT NOT NULL
);

5️⃣ Run the Server

npx nodemon server.js

Expected output:

Server running on http://localhost:4000
Connected to MySQL
Users table ready

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🔗 API Endpoints

👤 User Entity (/api/users)

Method	Endpoint	Description	Example Body (JSON)
POST	/api/users	Create new user	{ "name": "Rebira", "email": "rebira@example.com", "age": 22 }
GET	/api/users	List all users	N/A
GET	/api/users/:id	Get user by ID	N/A
PUT	/api/users/:id	Update user info	{ "age": 23 }
DELETE	/api/users/:id	Delete a user	N/A

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Testing the API

Using Postman

• Import endpoints manually and test CRUD operations.

Using cURL

Create a user:

curl -X POST http://localhost:4000/api/users \
-H "Content-Type: application/json" \
-d '{"name":"Rebira","email":"rebira@example.com","age":22}'

Get all users:

curl -X GET http://localhost:4000/api/users

Update a user:

curl -X PUT http://localhost:4000/api/users/1 \
-H "Content-Type: application/json" \
-d '{"age":23}'

Delete a user:

curl -X DELETE http://localhost:4000/api/users/1

Using MySQL CLI / Workbench

USE crud_db;
SELECT * FROM users;

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Skills Demonstrated

• Designing database schema in MySQL
• SQL basics: INSERT, SELECT, UPDATE, DELETE
• Building REST APIs with Node.js + Express
• Database integration using mysql2
• API testing with Postman / cURL

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Author

Rebira Adugna Software Engineering Student | Full Stack & Cloud Enthusiast ASTU, Ethiopia