On Fri, Jan 7, 2011 at 5:21 PM, Oliver Kohll - Mailing Lists < oliver.li...@gtwm.co.uk> wrote:
> Charts are updated once a day overnight, or cached whenever someone looks > at them in the system underlying the dashboard, so they are at most one day > old. A chart is also updated when a user clicks on it to drill down to the > data. > > Of course what you decide depends on what the business use case is and what > demands there are on the system. In my cases so far the slowest charts take > 1 or 2 seconds to generate by SQL so if necessary, each could be loaded in > in real time over AJAX, though that hasn't been needed yet. > We found for our use case that customers don't like "1 day old" reports. We've moved much of our dashboard statistics to trigger-based materialized view, so whenever they reload, they get current numbers and the cost to compute those numbers has already been amortized over the metric-gazillion updates and inserts that comprise them. :) Computing them on-the-fly is just too time consuming and people don't like to wait, either.
