JDBC常用

import java.sql.*;  //1 
String url = "jdbc:mysql://localhost:3306/数据库名`?useUnicode=true&characterEncoding=UTF-8;
String username = "root";
String password = "root";

8.0以上
		String url="jdbc:mysql://localhost:3306/student?"+"useSSL=false&serverTimezone=UTC";
			String user="root";
			String password="root";
		Class.forName("com.mysql.cj.jdbc.Driver");
		public static void main(String[] args) throws SQLException {
			Connection connection=null;
			Statement statement;
			ResultSet rs;
			
			try {
				Class.forName("com.mysql.cj.jdbc.Driver");
			} catch (Exception e) {
				System.out.println(e);
			}
			String url="jdbc:mysql://localhost:3306/student?"+"useSSL=false&serverTimezone=UTC";
			String user="root";
			String password="root";
			try {
				connection=DriverManager.getConnection(url,user,password);
			}catch (Exception e) {
				// TODO: handle exception
			System.out.println(e);
			}
			try {
				statement=(Statement) connection.createStatement();
				rs=((java.sql.Statement) statement).executeQuery("select * from test where c_grade>60&&java_grade>60");
				while(rs.next()) {
					String name=rs.getString(2);
					double c_grade=rs.getDouble(3);
					double java_grade=rs.getDouble(4);
					String stu_id=rs.getString(5);
					System.out.println("所有成绩大于60的 学生: "+ " 姓名" +name+c_grade+" "+java_grade+"  id "+stu_id);
				
				}
				connection.close();