JDBC1

public class TestInsert {
    public static void main(String[] args){
        //声明jdbc变量
        Connection conn=null;
        Statement stmt=null;
        //声明JDBC参数
            String driver="oracle.jdbc.driver.OracleDriver";
            String url="jdbc:oracle:thin:@localhost:1521:orcl";
            String username="scott";
            String password="oracle";
        //1 加载驱动类
        try {
            Class.forName(driver);
            //2 获取数据库连接对象(连接指定的数据库)
            conn=DriverManager.getConnection(url,username,password);
            //3 获取sql命令对象(编译和发送sql命令给数据库)
            stmt=conn.createStatement();
            //4 创建sql命令
            String sql="insert into dept values(1,‘清华‘,‘北京‘)";
            //5 指定sql命令
            int i=stmt.executeUpdate(sql);
            System.out.println("执行结果:"+i);
            
        } catch (ClassNotFoundException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        } catch (SQLException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }finally{
            //6 关闭资源
            try {
                stmt.close();
            } catch (SQLException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            }
            try {
                conn.close();
            } catch (SQLException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            }
        }
        
    }
}

public class TestUpdate {
    public static void main(String[] args) throws ClassNotFoundException, SQLException {
        //1加载驱动
        Class.forName("oracle.jdbc.driver.OracleDriver");
        //2创建连接对象
        Connection conn=DriverManager.getConnection("jdbc:oracle:thin:@localhost:1521:orcl", "scott","oracle");
        //3创建sql命令对象
        Statement stmt=conn.createStatement();
        //4创建sql命令
        String sname="张三";
        String sql="update student set sname=‘"+sname+"‘ where snum=2";
        //5执行sql命令
        int i=stmt.executeUpdate(sql);
        System.out.println(i);
        //6关闭资源
        stmt.close();
        conn.close();
        
    }
}

public class TestDel {
    public static void main(String[] args) throws ClassNotFoundException, SQLException {
        //1 加载驱动
            Class.forName("oracle.jdbc.driver.OracleDriver");
        //2创建连接对象
            Connection conn=DriverManager.getConnection("jdbc:oracle:thin:@LocalHost:1521:orcl", "scott", "oracle");
        //3创建sql命令对象
            Statement stmt=conn.createStatement();
        //4创建sql命令
            String sql="delete from student where snum=2";
        //5执行sql命令
            int i=stmt.executeUpdate(sql);
            System.out.println("删除数据量:"+i);
        //6关闭资源
            stmt.close();
            conn.close();
    }
}