『Web』Jaba_Web-JDBC 查询记录操作模板

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

public class Select {

    public static void main(String[] args) throws Exception {

    	String driverName = "com.mysql.cj.jdbc.Driver"; // 驱动程序名
    	String userName = "root"; // 数据库用户名
    	String userPwd = ""; // 密码
    	String dbName = "students"; // 数据库名
    	String url = "jdbc:mysql://localhost:3306/" + dbName + "?useSSL=false&serverTimezone=UTC"; // 形成带数据库读写编码的数据库连接字

    	Class.forName(driverName); // 加载并注册驱动程序
    	Connection conn = DriverManager.getConnection(url, userName, userPwd);// 创建连接对象
    	if (!conn.isClosed())
    		System.out.println("Succeeded connecting to the Database!");
    	Statement stmt = conn.createStatement();// 在桥conn上直接创建一辆汽车

    	String sql = "select * from stu where cj>=0 and cj<=100";
    	PreparedStatement pstmt = conn.prepareStatement(sql);

    	ResultSet rs = pstmt.executeQuery();// 执行，得到查询结果集合
    	System.out.println("记录号	 学号		姓名		成绩");
    	while (rs.next()) {
    		int a = rs.getRow();
    		int b = rs.getInt("xh");
    		String c = rs.getString("name");
    		int d = rs.getInt("cj");
    		System.out.println(a + " | " + b + " | " + c + " | " + d);
    	}

    	pstmt.close();
    	stmt.close();
    	conn.close();

    }

}