JDBC：操作所有关系型数据库的规则，即接口；各个数据库厂商去实现接口提供所谓的驱动jar

1：导入jar包

2：注册驱动

3：获取数据库连接对象Connection

4: 定义Sql

5: 获取Statement对象

6 执行sql接收返回结果 resultset

7：释放资源

package cn.jdbc;import com.mysql.jdbc.Driver;import java.sql.*;public class Demo1 { public static void main(String[] args) { String url = "jdbc:mysql://localhost:3306/day11"; String username = "root"; String password = "123456"; try { Class.forName("com.mysql.jdbc.Driver"); //将Driver类加载到内存 就会自动执行以下的静态代码块 // com.mysql.jdbc.Driver 通过查看源码Driver中含有以下静态代码块// static {// try {// DriverManager.registerDriver(new Driver());// } catch (SQLException var1) {// throw new RuntimeException("Can‘t register driver!");// }// } Connection cn = DriverManager.getConnection(url,username,password); String sql = "select * from day11"; PreparedStatement sta = cn.prepareStatement(sql); ResultSet rs = sta.executeQuery(); while (rs.next()){ int id = rs.getInt(1); String name = rs.getString(2); System.out.println(id+"___"+name); } rs.close(); sta.close(); cn.close(); } catch (Exception e) { e.printStackTrace(); } }}