1.1新建项目

选择Spring Initializr或者maven项目都可以

初始化好的项目

1.2 引pom

完全可以和java项目中引入依赖画等号
引入SQLServer的驱动包 还有我们要来操作数据库的Mybatis -plus

 <!--lombok用来简化实体类：需要安装lombok插件-->
        <dependency>
            <groupId>org.projectlombok</groupId>
            <artifactId>lombok</artifactId>
        </dependency>
        <!--for SqlServer-->
        <dependency>
            <groupId>com.microsoft.sqlserver</groupId>
            <artifactId>sqljdbc4</artifactId>
            <version>4.0</version>
        </dependency>
        <dependency>
            <groupId>com.baomidou</groupId>
            <artifactId>mybatis-plus-boot-starter</artifactId>
            <version>3.0.5</version>
        </dependency>

1.3 改yml

spring:
  datasource:
    driver-class-name: com.microsoft.sqlserver.jdbc.SQLServerDriver
    url: jdbc:sqlserver://localhost:1433;databaseName=demo01
    username: sa
    password: 123456rw

1.4新建实体类绑定表

新建User表和数据库中表帮绑定

@Data
@TableName("user1")
public class User {


    private Integer id;

    private String name;

}

1.5 建Mapper接口

@Repository
public interface UserMapper extends BaseMapper<User> {

}

1.6让启动时扫描dao层mapper接口

@SpringBootApplication
@MapperScan("com.rw.Mapper")
public class Main {
    public static void main(String[] args) {
        SpringApplication.run(Main.class, args);
    }
}

1.7写接口去测试

@Controller
public class TestController {
    @Autowired
    private UserMapper userMapper;
    @RequestMapping("getAllUser")
    @ResponseBody//把返回值打印到页面（JSON）
    public List<User> getAlluser(){
        //queryWrapper 查询条件 如果过传递 null 就是查询所有数据
        //先创建一个条件对象
        QueryWrapper<User> queryWrapper=new QueryWrapper<>();
        //添加条件
        //eq 是等于 查询id==1 的数据
        //queryWrapper.eq("id","2");
        /**
         * ne 是不等于
         */
       //queryWrapper.ge("id","5");
        //queryWrapper.between("id",2,5);
        //queryWrapper.like("name","小");
        queryWrapper.orderByDesc("id");
        return userMapper.selectList(queryWrapper);
    }

    @ResponseBody
    @RequestMapping("/add")
    public String add(){
        User user=new User();
        user.setId(11);
        user.setName("小王");
        int insert = userMapper.insert(user);
        if (insert>0){
            return "添加成功！";
        }else {
            return "添加失败！";
        }
    }
    @RequestMapping("/update")
    @ResponseBody
    public String update(){
        //1.查询要修改的内容
        User user = userMapper.selectById("3");
        System.out.println(user);
        //2.修改
        user.setName("New Hello");
        //userMapper.updateById() 根据你user的id进行修改
        int i = userMapper.update(user,new QueryWrapper<User>().eq("id","3"));
        if (i>0){
            System.out.println("修改成功！");
            return "修改成功！";
        }else {
            System.out.println("修改失败！");
            return "修改失败";
        }
    }
    @RequestMapping("/delete")
    @ResponseBody
    public String delete(){
        //创建一个条件对象
        QueryWrapper<User> wrapper=new QueryWrapper();
        //添加条件
        /**
         * 删除的是 name=New Hello 这条数据
         */
        wrapper.eq("name","New Hello");
        int delete = userMapper.delete(wrapper);
        if (delete>0){
            return "删除成功！";
        }else {
            return "删除失败！";
        }
    }
}