For example, there's a "completely dead" keyword which currently has 0 searches so it doesn't even show up in the tool. Now suppose that starting tommorow the keyword gets enough searches (per day on average?) to be shown in the tool. How much time will it take for the tool to display the keyword and corresponding search quantity? I guess this is inter-linked to a bunch of related questions... such as .. how often is Overture's search database updated? When is the update date? Etc., etc.
To be honest, I already knew that. My questions seeks more detailed information such as on what dates, when during the month the database is updated, are there "cut-off" dates and so on.
there's no specific time for that, it's depends on the span of times and number of sites need for an update. remember that there's always an equation for such process..
Span of times? number of sites need for an update? I'm sorry I don't understand what you're talking about. Can you please explain?