SpringBoot整合MyBatisPlus

-- 删除tb_brand表
drop table if exists tb_brand;
-- 创建tb_brand表
create table tb_brand
(
    -- id 主键
    id           int primary key auto_increment,
    -- 品牌名称
    brand_name   varchar(20),
    -- 企业名称
    company_name varchar(20),
    -- 排序字段
    ordered      int,
    -- 描述信息
    description  varchar(100),
    -- 状态：0：禁用  1：启用
    status       int
);
-- 添加数据
insert into tb_brand (brand_name, company_name, ordered, description, status)
values ('三只松鼠', '三只松鼠股份有限公司', 5, '好吃不上火', 0),
       ('华为', '华为技术有限公司', 100, '华为致力于把数字世界带入每个人、每个家庭、每个组织，构建万物互联的智能世界', 1),
       ('小米', '小米科技有限公司', 50, 'are you ok', 1);

<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
  xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 https://maven.apache.org/xsd/maven-4.0.0.xsd">
  <modelVersion>4.0.0</modelVersion>
  <parent>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-starter-parent</artifactId>
    <version>2.7.6</version>
    <relativePath/> <!-- lookup parent from repository -->
  </parent>
  <groupId>com.example</groupId>
  <artifactId>SpringBootMybatis-plus</artifactId>
  <version>0.0.1-SNAPSHOT</version>
  <name>SpringBootMybatis-plus</name>
  <description>SpringBootMybatis-plus</description>
  <properties>
    <java.version>1.8</java.version>
  </properties>
  <dependencies>
    <dependency>
      <groupId>com.baomidou</groupId>
      <artifactId>mybatis-plus-boot-starter</artifactId>
      <version>3.4.3</version>
    </dependency>
    <dependency>
      <groupId>mysql</groupId>
      <artifactId>mysql-connector-java</artifactId>
      <scope>runtime</scope>
    </dependency>
    <dependency>
      <groupId>org.springframework.boot</groupId>
      <artifactId>spring-boot-starter-test</artifactId>
      <scope>test</scope>
    </dependency>
  </dependencies>
  <build>
    <plugins>
      <plugin>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-maven-plugin</artifactId>
      </plugin>
    </plugins>
  </build>
</project>

# 数据库配置信息
spring:
  datasource:
    driver-class-name: com.mysql.cj.jdbc.Driver
    url: jdbc:mysql://localhost:3306/mybatis
    username: root
    password: 123456
# 设置Mp相关配置
mybatis-plus:
  global-config:
    db-config:
      table-prefix: tb_ # 这里写数据库表的前缀

package com.example.springbootmybatisplus.domain;
public class Brand {
    private Integer id;
    private String brand_name;
    private String companyName;
    private Integer ordered;
    private String description;
    private boolean status;
    @java.lang.Override
    public java.lang.String toString() {
        return "brand{" +
                "id=" + id +
                ", brand_name='" + brand_name + '\'' +
                ", companyName='" + companyName + '\'' +
                ", ordered=" + ordered +
                ", description='" + description + '\'' +
                ", status=" + status +
                '}';
    }
    public Integer getId() {
        return id;
    }
    public void setId(Integer id) {
        this.id = id;
    }
    public String getBrand_name() {
        return brand_name;
    }
    public void setBrand_name(String brand_name) {
        this.brand_name = brand_name;
    }
    public String getCompanyName() {
        return companyName;
    }
    public void setCompanyName(String companyName) {
        this.companyName = companyName;
    }
    public Integer getOrdered() {
        return ordered;
    }
    public void setOrdered(Integer ordered) {
        this.ordered = ordered;
    }
    public String getDescription() {
        return description;
    }
    public void setDescription(String description) {
        this.description = description;
    }
    public boolean isStatus() {
        return status;
    }
    public void setStatus(boolean status) {
        this.status = status;
    }
}

package com.example.springbootmybatisplus.dao;
import com.example.springbootmybatisplus.domain.Brand;
import org.apache.ibatis.annotations.Mapper;
import org.apache.ibatis.annotations.Select;
import java.awt.print.Book;
@Mapper
public interface BrandDao {
    @Select("select * from tb_brand where id = #{id}")
    public Brand getById(Integer id);
}

package com.example.springbootmybatisplus;
import com.example.springbootmybatisplus.dao.BrandDao;
import com.example.springbootmybatisplus.domain.Brand;
import org.junit.jupiter.api.Test;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.test.context.SpringBootTest;
@SpringBootTest
class SpringBootMybatisPlusApplicationTests {
  @Autowired
  private BrandDao brandDao;
  @Test
  void contextLoads() {
    System.out.println(brandDao.getById(1));
  }
}