一、场景说明

在项目中，可能有些同事需要查询线上数据库的数据，但又不能泄露密码给他们，手写一个程序方便他们查询。

二、Java代码

需要引入mysql驱动包：downloads.mysql.com

// mysql8.0以上版本com.mysql.jdbc.Driver 更换为 com.mysql.cj.jdbc.Driver
private static final String driver = "com.mysql.jdbc.Driver"; 
private static final String con_url = "jdbc:mysql://localhost:3306/test?useUnicode=true&useSSL=false&characterEncoding=utf8";
private static final String user_name = "root";
private static final String user_passward = "forlan";

// 驱动只需要加载一次，所以放在静态代码块里面
static {
	try {
		Class.forName(driver);
	} catch (ClassNotFoundException e) {
		e.printStackTrace();
	}
}

public static void main(String[] args) {
	ResultSet rs = null;
	try (Connection connection = DriverManager.getConnection(con_url, user_name, user_passward);
		 Statement stmt = connection.createStatement(); Scanner sc = new Scanner(System.in)) {
		while (true) {
			System.out.println("请输入要执行的sql：");
			String sql = sc.nextLine();
			StringBuilder sb = new StringBuilder();
			rs = stmt.executeQuery(sql);
			ResultSetMetaData metaData = rs.getMetaData();
			while (rs.next()) {
				for (int i = 0; i < metaData.getColumnCount(); i++) {
					String col_name = metaData.getColumnName(i + 1);// 获取列名
					sb.append(col_name).append("=").append(rs.getObject(col_name)).append(";");
				}
				sb.append("\n");
			}
			System.out.println(sb.toString());
		}
	} catch (Exception e) {
		System.out.println("执行失败，请联系管理员处理");
		e.printStackTrace();
	}finally {
		try {
			rs.close