搭建步骤
- 准备数据库
- 官网下载数据库连接驱动jar 包。https://downloads.mysql.com/archives/c-j/
- 创建 java 项目,在项目下创建 lib 文件夹,将下载的驱动 jar 包复制到文件夹里
- 选中 lib 文件夹右键 -> Add as Library,与项目集成
- 编写代码
代码实现
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);
java 代码
package com.atguigu.base;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.Statement;
public class JDBCBase {
public static void main(String[] args) throws Exception {
Class.forName("com.mysql.cj.jdbc.Driver");
String url = "jdbc:mysql://localhost:3306/atguigudb";
String username = "root";
String password = "123456";
Connection connection = DriverManager.getConnection(url, username, password);
Statement statement = connection.createStatement();
String sql = "select emp_id, emp_name, emp_salary, emp_age from t_emp";
ResultSet resultSet = statement.executeQuery(sql);
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);
}
resultSet.close();
statement.close();
connection.close();
}
}