package ts.jsj.lyh;

import java.sql.*;

/** *//**
* 使用JDBC連接數(shù)據(jù)庫MySQL的過程
* DataBase：JSJ， table：student；
* @author DuChangfeng 2008 09 18
*/
public class JDBCTest {

public static Connection getConnection() throws SQLException,
java.lang.ClassNotFoundException
{
//第一步：加載MySQL的JDBC的驅(qū)動
Class.forName("com.mysql.jdbc.Driver");

//取得連接的url,能訪問MySQL數(shù)據(jù)庫的用戶名,密碼；jsj：數(shù)據(jù)庫名
String url = "jdbc:mysql://localhost:3306/jsj";
String username = "root";
String password = "111";

//第二步：創(chuàng)建與MySQL數(shù)據(jù)庫的連接類的實例
Connection con = DriverManager.getConnection(url, username, password);
return con;
}


public static void main(String args[]) {
try
{
//第三步：獲取連接類實例con，用con創(chuàng)建Statement對象類實例 sql_statement
Connection con = getConnection();
Statement sql_statement = con.createStatement();

/** *//************ 對數(shù)據(jù)庫進行相關(guān)操作 ************/
//如果同名數(shù)據(jù)庫存在，刪除
//sql_statement.executeUpdate("drop table if exists student");
//執(zhí)行了一個sql語句生成了一個名為student的表
//sql_statement.executeUpdate("create table student (id int not null auto_increment, name varchar(20) not null default 'name', math int not null default 60, primary key (id) ); ");
//向表中插入數(shù)據(jù)
//sql_statement.executeUpdate("insert student values(1, 'liying', 98)");
//sql_statement.executeUpdate("insert student values(2, 'jiangshan', 88)");
//sql_statement.executeUpdate("insert student values(3, 'wangjiawu', 78)");
//sql_statement.executeUpdate("insert student values(4, 'duchangfeng', 100)");
//---以上操作不實用，但是列出來作為參考---

//第四步：執(zhí)行查詢，用ResultSet類的對象，返回查詢的結(jié)果
String query = "select * from student";
ResultSet result = sql_statement.executeQuery(query);
/** *//************ 對數(shù)據(jù)庫進行相關(guān)操作 ************/

System.out.println("Student表中的數(shù)據(jù)如下:");
System.out.println("------------------------");
System.out.println("學號" + " " + "姓名" + " " + "數(shù)據(jù)成績 ");
System.out.println("------------------------");

//對獲得的查詢結(jié)果進行處理，對Result類的對象進行操作
while (result.next())
{
int number = result.getInt("sno");
String name = result.getString("sname");
String mathScore = result.getString("sgrade");
//取得數(shù)據(jù)庫中的數(shù)據(jù)
System.out.println(" " + number + " " + name + " " + mathScore);
}

//關(guān)閉連接和聲明
sql_statement.close();
con.close();

} catch(java.lang.ClassNotFoundException e) {
//加載JDBC錯誤,所要用的驅(qū)動沒有找到
System.err.print("ClassNotFoundException");
//其他錯誤
System.err.println(e.getMessage());
} catch (SQLException ex) {
//顯示數(shù)據(jù)庫連接錯誤或查詢錯誤
System.err.println("SQLException: " + ex.getMessage());
}
}

}

String url = "jdbc:mysql://localhost:3306/jsj";
String username = "root";
String password = "111";

int number = result.getInt("sno");
String name = result.getString("sname");
String mathScore = result.getString("sgrade");