Sure, check out the ajax section,
http://api.jquery.com/category/ajax/ . What you'll want to do is create your web page that contains the jQuery. That jQuery will execute one of the ajax methods, probably get() or ajax(), and then in its response handler it would process whatever it gets back.
The ajax method will call a server side php page that will access your database and return the value of the column.
This is sort of a high level view, if you want something more specific post a few more details about what your doing and how it is triggered and what the next steps are. But this should be enough to get you started.
Dave