Try it out below, you can see instant responses from the server back to flex creating a very responsive and realtime feel. The search is looking through over 30,000 records. View source is enabled as well. Click on the Search text field and try searching for general things like the letter “A” or more fine grained terms like “Led”. The search polls the database on a short interval using setTimeout().

private function onKeyUp( e:KeyboardEvent ):void
{
	if( TextInput(e.currentTarget).text.length != 0 )
	{
		__interval = setTimeout(query, 100);
	}
	else
	{
		dgUserRequest.visible = false;
	}
}

You can modify the interval length, but from my testing I felt that 100 milliseconds was a good time for someone to type letter by letter and see instant responses, as well as not slow someone down who types rather fast and knows the search terms they are looking for.

Source includes the MySQL database, Request.php which proctors the requests, and all the flex goodness. Source can be found here: http://projects.lejnieks.com/flex_inline_search_poc/inline_search.html