增删改查——Statement接口-蒲公英云

增删改查——Statement接口

迷南。 2023-08-17 16:09 233阅读 0赞

1、增加数据表中的元组

package pers.datebase.zsgc;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.SQLException;
import java.sql.Statement;
public class JDBC {
    public static void main(String[] args) throws ClassNotFoundException,
            SQLException {
        // 加载驱动
        Class.forName("com.mysql.jdbc.Driver");
        // 链接到数据库
        String url = "jdbc:mysql://localhost:3306/student mangement system";
        String username = "root";
        String password = "root";
        Connection con = DriverManager.getConnection(url, username, password);
        // 获取到SQL语句的执行者对象
        Statement stat = con.createStatement();
        // 增加
        stat.executeUpdate("insert into student(studentno,sname,sex,birthday,classno,point,phone,email)"
                + "values('201712219','张涵','女','1989-12-18','080601','666','15878945612','han@163.com')");
        // 释放资源
        stat.close();
        con.close();
    }
}

2、删除元组

package pers.datebase.zsgc;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.SQLException;
import java.sql.Statement;
public class JDBC {
    public static void main(String[] args) throws ClassNotFoundException,
            SQLException {
        // 加载驱动
        Class.forName("com.mysql.jdbc.Driver");
        // 链接到数据库
        String url = "jdbc:mysql://localhost:3306/student mangement system";
        String username = "root";
        String password = "root";
        Connection con = DriverManager.getConnection(url, username, password);
        // 获取到SQL语句的执行者对象
        Statement stat = con.createStatement();
        // 删除
        String sql = "delete from student where sname='张涵'"; // SQL语句
        stat.executeUpdate(sql); // 将sql语句上传至数据库执行
        // 释放资源
        stat.close();
        con.close();
    }
}

3、修改元组

package pers.datebase.zsgc;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.SQLException;
import java.sql.Statement;
public class JDBC {
    public static void main(String[] args) throws ClassNotFoundException,
            SQLException {
        // 加载驱动
        Class.forName("com.mysql.jdbc.Driver");
        // 链接到数据库
        String url = "jdbc:mysql://localhost:3306/student mangement system";
        String username = "root";
        String password = "root";
        Connection con = DriverManager.getConnection(url, username, password);
        // 获取到SQL语句的执行者对象
        Statement stat = con.createStatement();
        String sql="update student set classno='201718' where sname='平靖' ";   //SQL语句
        stat.executeUpdate(sql);         //将sql语句上传至数据库执行
        // 释放资源
        stat.close();
        con.close();
    }
}

4、查询数据表

package pers.datebase.zsgc;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;
public class JDBC {
    public static void main(String[] args) throws ClassNotFoundException,
            SQLException {
        // 加载驱动
        Class.forName("com.mysql.jdbc.Driver");
        // 链接到数据库
        String url = "jdbc:mysql://localhost:3306/student mangement system";
        String username = "root";
        String password = "root";
        Connection con = DriverManager.getConnection(url, username, password);
        // 获取到SQL语句的执行者对象
        Statement stat = con.createStatement();
        String sql="select * from score";           //sql语句
        ResultSet rs=stat.executeQuery(sql);          //ResultSet 是java中执行select后，返回的结果集类。 rs 就是结果集的变量。
        while(rs.next()){    //next（）获取里面的内容
            System.out.println(rs.getString(1)+" "+rs.getString(2)+" "+rs.getString(3)+""+rs.getString(4));
        }
        // 释放资源
        stat.close();
        con.close();
        rs.close();
    }
}