JDBC 快速入门

create database if not exists `atguigudb`;

use atguigudb;

create table t_emp (
    emp_id int auto_increment comment '员工编号' primary key,
    emp_name varchar(100) not null comment '员工姓名',
    emp_salary double(10, 5) not null comment '员工工资',
    emp_age int not null comment '员工年龄'
);

insert into t_emp(emp_name, emp_salary, emp_age)
values ('andy', 777.77, 32),
       ('大风哥', 666.66, 41),
       ('康师傅', 111, 23),
       ('Cavin', 123, 26),
       ('小鱼儿', 123, 28);

package com.atguigu.base;

import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.Statement;

/**
 * Copyright (C) 2024 - 2024 Jasonakeke， Inc. All Rights Reserved
 *
 * @Desc :
 * @Time : 2024/10/3 15:28
 * @Author : Code_By_Jasonakeke
 * @Email : 2284037977@qq.com
 * @Class : JDBCBase
 * @IDE : IntelliJ IDEA
 */
public class JDBCBase {

	public static void main(String[] args) throws Exception {
		// 1.注册驱动
		Class.forName("com.mysql.cj.jdbc.Driver");

		// 2.获取连接对象
		String url = "jdbc:mysql://localhost:3306/atguigudb";
		String username = "root";
		String password = "123456";
		Connection connection = DriverManager.getConnection(url, username, password);

		// 3.获取执行 SQL 语句的对象
		Statement statement = connection.createStatement();

		// 4.编写 SQL 语句执行，得到返回的结果集
		String sql = "select emp_id, emp_name, emp_salary, emp_age from t_emp";
		ResultSet resultSet = statement.executeQuery(sql);

		// 5.处理结果：遍历 resultSet 结果集
		while (resultSet.next()) {
			int empId = resultSet.getInt("emp_id");
			String empName = resultSet.getString("emp_name");
			double empSalary = resultSet.getDouble("emp_salary");
			int empAge = resultSet.getInt("emp_age");
			System.out.println(empId + "\t" + empName + "\t" + empSalary + "\t" + empAge);
		}

		// 6.释放资源(先开后关)
		resultSet.close();
		statement.close();
		connection.close();
	}
}