Angular 2:当MySQL数据库发生变化时,应用程序上的自动数据刷新

I'm working on an angular 2 web app, fetching the data from the MySQL database using php and display on the browser. But when I modify the data from the database, the changes are not automatically reflected in the browser.

I have to refresh the page manually to see changes.

So, how can I reflect those changes without manually refreshing the page?