real time notifications with jquery and php

I'm trying to find some php and jquery tutorial/plugin or piece of code which enables to get the real time notifications. For example, if some data is inserted in the database, i want to receive the notification on the webpage in real time without refresh etc. If you开发者_如何学Python know any resource, please let me know. Bundle of thanks.

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You will need to poll the server, preferably using long polling (not trivial with PHP).

The server can respond blank, or a JSON message if there is something to be returned.

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here is periodic updater built as a jQuery plugin that tries to implement long polling and reduce the load on the server.

https://github.com/RobertFischer/JQuery-PeriodicalUpdater/