Sockets vs XMLRequest... ??

I am currently working on a project (some may have experienced the test AJAX chatroom I made a few weeks ago).

Anyways, this project requires the ability of many computers gathering up to date information (to the second) from a database.

With the XMLRequest, I can manipulate the data and retrieve it exactly as I need it. The only problem is that each and every second (on every computer on the page) a new XML request is being generated. This seems some what feasible, however the bandwidth consumption can start to get pretty agressive.

A socket connection could solve this, but data cannot be retrieved from a database through the use of a socket, only retrieve the data that is currently being sent. My understanding of sockets is very limited, so if anyone has a good tutorial to which can show the way of using sockets, for instance to retrieve the next set of messages that are awaiting. Or maybe not even messages, but a way to extract specific data. Like I said, my understanding of sockets is very limited and if this can be used versus an XMLRequest this would be awesome.

Thoughts/ideas/suggestions or general comments on sockets alone are more then welcome!!