How to implement chat using jQuery, PHP, and MySQL?

Question

I have made a chat script using php, mysql and jquery. It uses json to get data from the server. It makes fixed interval requests to the server with the lastly fetched message id to get new messages from the server. But when multiple users will be chatting then thousands and crores of requests will be made to the server within an hour and the hosting people will block it for sure.

Th gmail chat uses socket I think. Because it does not sends fixed interval requests for sure. Could any one of you please give me some sample code or some direction to solve this issue.

Please I need help desperately.

Many thanks in advance. My respect and regards for all.

Answer 1

If the host you are using would "block it for sure" if it's making that many requests, then you may want to consider getting a different host or upgrading your hosting package before worrying about your code. Check out how Facebook implements their chat:

The method we chose to get text from one user to another involves loading an iframe on each Facebook page, and having that iframe's Javascript make an HTTP GET request over a persistent connection that doesn't return until the server has data for the client. The request gets reestablished if it's interrupted or times out. This isn't by any means a new technique: it's a variation of Comet, specifically XHR long polling, and/or BOSH.