how to set countdown of time in jquery...
in my database i have one field which content time in int format..

I don't believe you can do it with jQuery, that's as easy as that.

jQuery is client-side, this is code provided to you by server, and your browser manages what you see by it. If server sends you "move block to left 500px", your browser does it, because that's what website requests.

The database requires server-sided langauge. Which does whatever it has to do and your browser doesn't get anything to see out of it, except when file exclusively wants to show you something.