MySQL最终弹-并发（脏读，不可重复读，幻读及区别），JDBC的使用和安装,最全万字（二）

import com.mysql.jdbc.jdbc2.optional.MysqlDataSource;
import javax.sql.DataSource;
import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.SQLException;
public class Main {
   public static void main(String[] args) throws SQLException {
//1.创建数据源
      DataSource dataSource=new MysqlDataSource();
      ((MysqlDataSource)dataSource).setUrl("jdbc:mysql://127.0.0.1:3306/java108?characterEncoding=utf8&&useSSL=false");
//设置你的数据库名字的密码，不是随便设置哈，你自己的数据库密码，root也是不能乱设置
      ((MysqlDataSource)dataSource).setUser("root");
      ((MysqlDataSource)dataSource).setPassword("lcl15604007179");
//2.和数据库服务器建立链接，认准第二个sql的Connection,第一个com那个是mysql的驱动包
      Connection connection=dataSource.getConnection();
//构造SQL语句
      String sql=" insert student values(1,'张三') ";
      PreparedStatement statement=connection.prepareStatement(sql);
//4.执行SQL语句
      int n=statement.executeUpdate();     //返回有几行收到了影响
      System.out.println(n);
//5.释放必要资源，关闭链接 -注意关闭顺序，后创建的先关闭
      statement.close();          //创建的对象都会持有一些计算机硬件，软件中资源
      connection.close();
   }
}

import com.mysql.jdbc.jdbc2.optional.MysqlDataSource;
import javax.sql.DataSource;
import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.SQLException;
import java.util.Scanner;
public class Main {
   public static void main(String[] args) throws SQLException {
      Scanner scanner=new Scanner(System.in);
      System.out.println("输入姓名");
      String name=scanner.nextLine();
      System.out.println("输入数字");
      int id=scanner.nextInt();
//1.创建数据源
      DataSource dataSource=new MysqlDataSource();
      ((MysqlDataSource)dataSource).setUrl("jdbc:mysql://127.0.0.1:3306/java108?characterEncoding=utf8&&useSSL=false");
      ((MysqlDataSource)dataSource).setUser("root");
      ((MysqlDataSource)dataSource).setPassword("lcl15604007179");
//2.和数据库服务器建立链接
      Connection connection=dataSource.getConnection();
//3.构造SQL语句
      String sql=" insert student values(?,?) ";
      PreparedStatement statement=connection.prepareStatement(sql);
      statement.setInt(1,id);          //表示的是第一个问号
      statement.setString(2,name);     //表示的是第二个问号
//4.返回受影响的行数
      int n=statement.executeUpdate();
      System.out.println(n);
//5.释放必要资源，关闭链接
      statement.close();
      connection.close();
   }
}

import com.mysql.jdbc.jdbc2.optional.MysqlDataSource;
import javax.sql.DataSource;
import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.SQLException;
import java.util.Scanner;
public class Main {
   public static void main(String[] args) throws SQLException {
      Scanner scanner=new Scanner(System.in);
      System.out.println("输入姓名");
      String name=scanner.nextLine();
//1.创建数据源
      DataSource dataSource=new MysqlDataSource();
      ((MysqlDataSource)dataSource).setUrl("jdbc:mysql://127.0.0.1:3306/java108?characterEncoding=utf8&&useSSL=false");
      ((MysqlDataSource)dataSource).setUser("root");
      ((MysqlDataSource)dataSource).setPassword("lcl15604007179");
//2.和数据库服务器建立链接
      Connection connection=dataSource.getConnection();
//3.构造SQL语句
      String sql=" delete  from student  where  name=? ";
      PreparedStatement statement=connection.prepareStatement(sql);
      statement.setString(1,name);
//4.执行SQL语句
      int n=statement.executeUpdate();
      System.out.println(n);
//5关闭
      statement.close();
      connection.close();
   }
}

import com.mysql.jdbc.jdbc2.optional.MysqlDataSource;
import javax.sql.DataSource;
import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.util.Scanner;
public class Main {
   public static void main(String[] args) throws SQLException {
      Scanner scanner = new Scanner(System.in);
//1.创建数据源
      DataSource dataSource = new MysqlDataSource();
      ((MysqlDataSource) dataSource).setUrl("jdbc:mysql://127.0.0.1:3306/java108?characterEncoding=utf8&&useSSL=false");
      ((MysqlDataSource) dataSource).setUser("root");
      ((MysqlDataSource) dataSource).setPassword("lcl15604007179");
//2.和数据库服务器建立链接
      Connection connection = dataSource.getConnection();
//构造SQL语句
      String sql = " select * from student   ";
      PreparedStatement statement = connection.prepareStatement(sql);
//4.执行查询操作，要使用excuteQuery,返回值是一个ResultSet类型的对象，表示了一个表格
      ResultSet resultSet = statement.executeQuery();
//遍历结果集合
      while (resultSet.next()) {
//获取这一行学号列
         int id = resultSet.getInt("id");
//获取姓名列
         String name = resultSet.getString("name");
         System.out.println("id: " +  id + ",name: " + name);
      }
      statement.close();
      connection.close();
   }
}

public class Main {
   public static void main(String[] args) throws SQLException {
      Scanner scanner = new Scanner(System.in);
      int student_id=scanner.nextInt();
//1.创建数据源
      DataSource dataSource = new MysqlDataSource();
        ((MysqlDataSource)dataSource).setUrl("jdbc:mysql://127.0.0.1:3306/java108? characterEncoding=utf8&&useSSL=false");             
      ((MysqlDataSource) dataSource).setUser("root");
      ((MysqlDataSource) dataSource).setPassword("lcl15604007179");
//2.和数据库服务器建立链接
      Connection connection = dataSource.getConnection();
//注意哈，这里面是id不是你写的那个变量student_id
      String sql = " select * from student   where id = ? ";
      PreparedStatement statement = connection.prepareStatement(sql);
      statement.setInt(1,student_id);
//4.执行SQL语句
      ResultSet resultSet = statement.executeQuery();
      while (resultSet.next()) {
         int id = resultSet.getInt("id");
         String name = resultSet.getString("name");
         System.out.println("id: " +  id + ",name: " + name);
      }
//5.注意关闭的时候result也需要关闭
      resultSet.close();
      statement.close();
      connection.close();
   }
}