Now that Power BI is finally available (I still use terms as “released” for software and “in production” for a service…) I made some test on the new Scheduled Refresh option that you have for your models (other info here.
First of all, the Refresh feature within the Excel workbook no longer works, at least when you are using Data Management Gateway – you need to schedule a refresh for that, and I think this is a good idea. The refresh time could be very slow and waiting 30 seconds or more without being able to interact with the workbook wasn’t good from the user experience point of view. Well done.
Now, when you schedule the refresh, you can set a frequency that can be daily or weekly. No intra-day updates, unfortunately. I think you might workaround this by creating several copies of the same workbook and then defining a different daily schedule for each copy, at different hours. I think that a more frequent update could be a good idea for certain businesses. Maybe with some limitation, but if the workbook is small I don’t see the real reason for such a limitation (considering that it could incentivize bad behaviors like the workaround I just described).
You can also request a manual refresh – the strange thing is that you can do that only after you defined a scheduled refresh (maybe I don’t need that, so I might create an unnecessary schedule just for a single manual refresh).
I observed that when you request a manual refresh, in reality you just put a request in an internal queue somewhere on the cloud. After you request a refresh, you cannot request a second one, because one refresh is running.
At this point, you see the status Running in the History tab:
In reality, chances are that you are just waiting but nothing is running. In fact, I have seen my workbook refreshed after 10 minutes, but history log says that execution time was only 28 seconds. For this reason I assume that there is a queue that handles these requests on the cloud and manual refresh can take so long to finish. However, the second execution required less than 2 minutes, so I am not sure it was because I refreshed a workbook on my tenant for the first time (maybe some deployment was involved) or I was just unlucky and my queue was particularly slow at the previous request.
I look forward to see more data sources supported by scheduled data refresh, and in particular Power Query would be an important step for making Power BI adoption even larger.
Originally appeared on: http://sqlblog.com/blogs/marco_russo/archive/2014/02/11/scheduled-data-refresh-in-power-bi.aspx