Connecting a MySQL database to your Spring Boot project is one of the most common and essential tasks for building real-world web applications. In this tutorial, we'll go step-by-step to set up and integrate MySQL into a Spring Boot application.

Prerequisites

Before we start, make sure you have the following installed:

• Java 17+
• Maven or Gradle
• MySQL Server (Running locally or remotely)
• Spring Boot (v3+)
• IDE such as IntelliJ IDEA or Eclipse

Step 1: Create a Spring Boot Project

You can create a Spring Boot project in two ways:

Option 1: Using Spring Initializr

1. Go to https://start.spring.io/
2. Choose:
   • Project: Maven Project
   • Language: Java
   • Spring Boot Version: 3.x
   • Dependencies:
     • Spring Web
     • Spring Data JPA
     • MySQL Driver
3. Click Generate, and extract the downloaded project.

Option 2: Using IDE (like IntelliJ or Eclipse)

• Go to File → New → Project → Spring Initializr
• Add the same dependencies mentioned above.

Step 2: Configure MySQL Database

Create a new MySQL database:

CREATE DATABASE springboot_db;

You can use any name for the database.

Step 3: Add Database Configuration in application.properties

In src/main/resources/application.properties , add:

# Database Configuration
spring.datasource.url=jdbc:mysql://localhost:3306/springboot_db
spring.datasource.username=root
spring.datasource.password=your_password
 
# JPA Configuration
spring.jpa.hibernate.ddl-auto=update
spring.jpa.show-sql=true
spring.jpa.properties.hibernate.dialect=org.hibernate.dialect.MySQL8Dialect

Explanation: - ddl-auto=update : Automatically creates or updates tables based on entity classes. - show-sql=true : Logs SQL queries to the console. - MySQL8Dialect : Optimizes Hibernate for MySQL 8.

Step 4: Create a JPA Entity

Inside src/main/java/com/example/demo/model , create a class named User.java :

package com.example.demo.model;
 
import jakarta.persistence.*;
 
@Entity
@Table(name = "users")
public class User {
 
    @Id
    @GeneratedValue(strategy = GenerationType.IDENTITY)
    private Long id;
 
    private String name;
    private String email;
 
    // Constructors
    public User() {}
    public User(String name, String email) {
        this.name = name;
        this.email = email;
    }
 
    // Getters & Setters
    public Long getId() { return id; }
    public String getName() { return name; }
    public void setName(String name) { this.name = name; }
    public String getEmail() { return email; }
    public void setEmail(String email) { this.email = email; }
}

Step 5: Create a Repository Interface

Inside src/main/java/com/example/demo/repository , create UserRepository.java :

package com.example.demo.repository;
 
import com.example.demo.model.User;
import org.springframework.data.jpa.repository.JpaRepository;
 
public interface UserRepository extends JpaRepository<User, Long> {
}

This gives you all CRUD methods (save, findAll, delete, etc.) without writing SQL manually.

Step 6: Create a Service and Controller

Service Layer

package com.example.demo.service;
 
import com.example.demo.model.User;
import com.example.demo.repository.UserRepository;
import org.springframework.stereotype.Service;
 
import java.util.List;
 
@Service
public class UserService {
 
    private final UserRepository repository;
 
    public UserService(UserRepository repository) {
        this.repository = repository;
    }
 
    public List<User> getAllUsers() {
        return repository.findAll();
    }
 
    public User addUser(User user) {
        return repository.save(user);
    }
}

Controller Layer

package com.example.demo.controller;
 
import com.example.demo.model.User;
import com.example.demo.service.UserService;
import org.springframework.web.bind.annotation.*;
 
import java.util.List;
 
@RestController
@RequestMapping("/api/users")
public class UserController {
 
    private final UserService service;
 
    public UserController(UserService service) {
        this.service = service;
    }
 
    @GetMapping
    public List<User> getUsers() {
        return service.getAllUsers();
    }
 
    @PostMapping
    public User createUser(@RequestBody User user) {
        return service.addUser(user);
    }
}

Step 7: Run the Application

Run the application using:

mvn spring-boot:run

Or run DemoApplication.java directly from your IDE.

Once it starts, visit:

• GET Users: http://localhost:8080/api/users\
• POST Users: http://localhost:8080/api/users

Sample JSON for POST request:

{
  "name": "Akshay",
  "email": "akshay@example.com"
}

Step 8: Verify in MySQL

Run this in your MySQL terminal:

SELECT * FROM users;

You should see your inserted data!

Common Troubleshooting Tips

   |  Ensure MySQL server is running and port is correct|

|Table doesn’t exist | Try spring.jpa.hibernate.ddl-auto=create for first run|

Conclusion

You've successfully integrated MySQL with Spring Boot! 🎉 Now your app can store and manage data efficiently with the power of Spring Data JPA.