How to develop a real time system using PHP & MySQL

I will be working on a project for my friend. It will involve handling real time user data. Like SO, I would like to let a user login with his/her OpenID. I want advice on

• MySQL db engine and or design for a real time system
• authentication mechanisms
• I am good at CodeIgniter and chances are I will be using it, any othe开发者_JAVA百科r suggestion
• jQuery has most supporter/users here on SO and I am comfortable with jQuery as well as Prototype, out of these two which one is better or there is any other competitor to these?

The system will have users, who will be using a stand-alone client that will communicate with centralised server, one can have a view of this data on web front end.

Similar Question : Is there a way to have PHP print the data to a web browser in real time?

Javascript library is your choice.

For real time web applications trends like WebSocket, Server-Sent Events are not supported across all platforms. You might consider checking Push Technology, Comet. Hope this gives you some direction.