使用SQL中的SELECT语句可以查询出数据库的全部结果,在JDBC的操作中数据库的所有查询记录将使用ResultSet进行接收,并使用ResultSet显示内容。
从user表中查询数据
//================================================= // File Name : MySQL_demo //------------------------------------------------------------------------------ // Author : Common import java.sql.*; //主类 //Function : MySQL_demo public class MySQL_demo { //定义MySQL的数据库驱动程序 public static final String DBDRIVER = "org.gjt.mm.mysql.Driver"; //定义MySQL数据库的连接地址 public static final String DBURL = "jdbc:mysql://localhost:3306/mysql_demo"; //MySQL数据库的连接用户名 public static final String DBUSER = "root"; //MySQL数据库的连接密码 public static final String DBPASS = "123456"; public static void main(String[] args) throws Exception { // TODO 自动生成的方法存根 Connection conn = null; //数据库连接 Statement stmt = null; //数据库操作 ResultSet rs = null; //保存查询结果 String sql = "SELECT id,name,password,age,sex,birthday FROM user"; Class.forName(DBDRIVER); //加载驱动程序 //连接MySQL数据库时,要写上连接的用户名和密码 conn = DriverManager.getConnection(DBURL,DBUSER,DBPASS); stmt = conn.createStatement(); //实例化Statement对象 rs = stmt.executeQuery(sql); //实例化ResultSet对象 while(rs.next()){ // int id = rs.getInt("id"); // String name = rs.getString("name"); // String pass = rs.getString("password"); // int age = rs.getInt("age"); // String sex = rs.getString("sex"); // Date d = rs.getDate("birthday"); int id = rs.getInt(1); String name = rs.getString(2); String pass = rs.getString(3); int age = rs.getInt(4); String sex = rs.getString(5); Date d = rs.getDate(6); System.out.println("编号:"+id); System.out.println("名字:"+name); System.out.println("密码:"+pass); System.out.println("年龄:"+age); System.out.println("性别:"+sex); System.out.println("生日:"+d); } rs.close(); //关闭结果集 stmt.close(); //操作关闭 conn.close(); //数据库关闭 } }