JDBC使用模板

柔情只为你懂 2022-10-16 00:46 139阅读 0赞

# JDBC使用模板 #

//1.导入驱动jar包
        //2.注册驱动
        Class.forName("com.mysql.jdbc.Driver");
        //3.获取数据库连接对象
        Connection conn = DriverManager.getConnection("jdbc:mysql://localhost:3306/school", "root", "123456");
        //4.定义sql语句
        String sql = "update user set username = 'qiqi' where userId = 1";
        //5.获取执行sql的对象 Statement
        Statement stmt = conn.createStatement();
        //6.执行sql
        int count = stmt.executeUpdate(sql);
        //7.处理结果
        System.out.println(count);
        //8.释放资源
        stmt.close();
        conn.close();

public static void main(String[] args)  {
            Connection conn = null;
            Statement stmt = null;
            try {
                //1.导入驱动jar包
                //2.注册驱动
                Class.forName("com.mysql.jdbc.Driver");
                //3.获取数据库连接对象
                conn = DriverManager.getConnection("jdbc:mysql:///school", "root", "123456");
                //4.定义sql语句
                String sql1 = "update user set username = 'zhier' where userId = 2";
                String sql2 = "Insert into user(userId,username,password) values (3,'sansan','123456')";
                String sql3 = "delete from user where userId = 3";
                //5.获取执行sql的对象 Statement
                stmt = conn.createStatement();
                //6.执行sql
                int i = stmt.executeUpdate(sql3);
                //7.处理结果
                System.out.println(i);
    
            } catch (ClassNotFoundException e) {
                e.printStackTrace();
            } catch (SQLException throwables) {
                throwables.printStackTrace();
            }finally {
                //8.释放资源
    //            stmt.close();
    //            conn.close()
                if (stmt != null){
                    try {
                        stmt.close();
                    } catch (SQLException throwables) {
                        throwables.printStackTrace();
                    }
                }
                if (conn != null){
                    try {
                        conn.close();
                    } catch (SQLException throwables) {
                        throwables.printStackTrace();
                    }
                }
            }
    
        }