Quick Start

We will demonstrate the powerful features of MyBatis-Plus through a simple demo. Before we begin, we assume you already have:

• A Java development environment and a corresponding IDE
• Familiarity with Spring Boot
• Familiarity with Maven or Gradle

---

Consider a User table with the following structure:

id	name	age	email
1	Jone	18	test1@baomidou.com
2	Jack	20	test2@baomidou.com
3	Tom	28	test3@baomidou.com
4	Sandy	21	test4@baomidou.com
5	Billie	24	test5@baomidou.com

The corresponding database Schema script is as follows:

schema-h2.sql

DROP TABLE IF EXISTS `user`;

CREATE TABLE `user`
(
    id BIGINT NOT NULL COMMENT 'Primary Key ID',
    name VARCHAR(30) NULL DEFAULT NULL COMMENT 'Name',
    age INT NULL DEFAULT NULL COMMENT 'Age',
    email VARCHAR(50) NULL DEFAULT NULL COMMENT 'Email',
    PRIMARY KEY (id)
);

The corresponding database Data script is as follows:

data-h2.sql

DELETE FROM `user`;

INSERT INTO `user` (id, name, age, email) VALUES
(1, 'Jone', 18, 'test1@baomidou.com'),
(2, 'Jack', 20, 'test2@baomidou.com'),
(3, 'Tom', 28, 'test3@baomidou.com'),
(4, 'Sandy', 21, 'test4@baomidou.com'),
(5, 'Billie', 24, 'test5@baomidou.com');

---

Did you know?

What do we need to do if we want to implement CRUD operations for this table using MyBatis-Plus from scratch?

Initialize Project

Create an empty Spring Boot project and add the H2 database for integration testing.

Tip

Click here Spring Initializer to quickly initialize a Spring Boot project

Add Dependencies

Introduce the MyBatis-Plus Starter dependency

Spring Boot 2

Maven

<dependency>
    <groupId>com.baomidou</groupId>
    <artifactId>mybatis-plus-boot-starter</artifactId>
    <version>3.5.12</version>
</dependency>

Gradle

implementation 'com.baomidou:mybatis-plus-boot-starter:3.5.12'

Spring Boot 3

Maven

<dependency>
    <groupId>com.baomidou</groupId>
    <artifactId>mybatis-plus-spring-boot3-starter</artifactId>
    <version>3.5.12</version>
</dependency>

Gradle

implementation 'com.baomidou:mybatis-plus-spring-boot3-starter:3.5.12'

Configuration

Add the relevant H2 database configuration to the application.yml configuration file:

application.yml

# DataSource Config
spring:
  datasource:
    driver-class-name: org.h2.Driver
    username: root
    password: test
  sql:
    init:
      schema-locations: classpath:db/schema-h2.sql
      data-locations: classpath:db/data-h2.sql

The configuration above is the database connection information that any Spring Boot project would configure. If you are using a different database, such as MySQL, you need to modify the corresponding configuration information.

Add the @MapperScan annotation to the Spring Boot startup class to scan the Mapper folder:

Application.java

@SpringBootApplication
@MapperScan("com.baomidou.mybatisplus.samples.quickstart.mapper")
public class Application {

    public static void main(String[] args) {
        SpringApplication.run(Application.class, args);
    }

}

Coding

Write the entity class User.java:

User.java

@Data
@TableName("`user`")
public class User {
    private Long id;
    private String name;
    private Integer age;
    private String email;
}

Note

The code above uses Lombok for code generation. If you are not comfortable with it, please generate the relevant Getter/Setter methods yourself.

Write the Mapper interface class UserMapper.java:

public interface UserMapper extends BaseMapper<User> {

}

Start Using

Add a test class for functional testing:

@SpringBootTest
public class SampleTest {

    @Autowired
    private UserMapper userMapper;

    @Test
    public void testSelect() {
        System.out.println(("----- selectAll method test ------"));
        List<User> userList = userMapper.selectList(null);
        Assert.isTrue(5 == userList.size(), "");
        userList.forEach(System.out::println);
    }

}

Tip

The parameter of the selectList() method in UserMapper is MP’s built-in condition wrapper Wrapper, so leaving it empty means no conditions.

Console Output:

User(id=1, name=Jone, age=18, email=test1@baomidou.com)
User(id=2, name=Jack, age=20, email=test2@baomidou.com)
User(id=3, name=Tom, age=28, email=test3@baomidou.com)
User(id=4, name=Sandy, age=21, email=test4@baomidou.com)
User(id=5, name=Billie, age=24, email=test5@baomidou.com)

Note

For complete code examples, please refer to: Spring Boot Quick Start Example | Spring MVC Quick Start Example

Summary

Through these simple steps, we have implemented the CRUD functions for the User table, without even needing to write an XML file!

From the steps above, we can see that integrating MyBatis-Plus is very simple. Just introduce the starter dependency and configure it briefly to use.

But the power of MyBatis-Plus goes far beyond these features. Want to learn more about the powerful features of MyBatis-Plus? Then keep reading!