springboot如何连接mysql增删改查？

1、在pom.xml中增加依赖，mysql与jdbc

		<dependency>
			<groupId>mysql</groupId>
			<artifactId>mysql-connector-java</artifactId>
		</dependency>

		<dependency>
			<groupId>org.springframework.boot</groupId>
			<artifactId>spring-boot-starter-jdbc</artifactId>
		</dependency>

#集成mysql数据库的配置
spring.datasource.driverClassName=com.mysql.cj.jdbc.Driver
spring.datasource.url=jdbc:mysql://localhost:3306/studentscon?useSSL=false&useUnicode=true&characterEncoding=utf-8&autoReconnect=true&serverTimezone=Asia/Shanghai
spring.datasource.username=root
spring.datasource.password=root

3、然后定义个entity实体类

public class Student {
    private int id;
    private String name;
    private String password;
    private String sex;
    private int age;

    public Student() {
    }

    public Student(int id, String name, String password, String sex, int age) {
        this.id = id;
        this.name = name;
        this.password = password;
        this.sex = sex;
        this.age = age;
    }

    @Override
    public String toString() {
        return "Student{" +
                "id=" + id +
                ", name='" + name + '\'' +
                ", password='" + password + '\'' +
                ", sex='" + sex + '\'' +
                ", age=" + age +
                '}';
    }

    public int getId() {
        return id;
    }

    public void setId(int id) {
        this.id = id;
    }

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

    public String getPassword() {
        return password;
    }

    public void setPassword(String password) {
        this.password = password;
    }

    public String getSex() {
        return sex;
    }

    public void setSex(String sex) {
        this.sex = sex;
    }

    public int getAge() {
        return age;
    }

    public void setAge(int age) {
        this.age = age;
    }
}

import com.example.demo.entity.Student;
import jakarta.annotation.Resource;
import org.springframework.jdbc.core.JdbcTemplate;
import org.springframework.jdbc.core.RowMapper;
import org.springframework.stereotype.Controller;
import org.springframework.ui.Model;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.servlet.ModelAndView;

import java.sql.ResultSet;
import java.sql.SQLException;
import java.util.List;

@Controller
public class TestController {

    @Resource    // 自动注入，spring boot会帮我们实例化一个对象
    private JdbcTemplate jdbcTemplate;   // 一个通过JDBC连接数据库的工具类，可以通过这个工具类对数据库进行增删改查


    public void mySqlTest(){
        String sql = "select id,name,password,sex,age from students";
        List<Student> students = jdbcTemplate.query(sql, new RowMapper<Student>() {
            @Override
            public Student mapRow(ResultSet resultSet, int i) throws SQLException {
                Student student = new Student();
                student.setId(resultSet.getInt("id"));
                student.setName(resultSet.getString("name"));
                student.setPassword(resultSet.getString("password"));
                student.setSex(resultSet.getString("sex"));
                student.setAge(resultSet.getInt("age"));
                return student;
            }
        });

        System.out.println("查询成功");
        for(Student s : students){
            System.out.println(s);
        }
    }

    // 返回整个页面
    @RequestMapping("/test/1")
    public String test(){
        this.mySqlTest();
        return "hello";

    }
}