Chart which updates upon refresh...but retains previous data??

[Creative_tree88]

Hi all - I'm not even sure this is possible, so just want to rule it out of a possible development.

We have connected to a database which allows us to see how many clients are waiting for an appt.  It is auto refreshed every hour.  Obviously, every hour, the numbers change.  What i'd love to show is how these numbers change throughout the day using the 'refresh' time to form the X axis of a chart.  So, a new refresh will add the new data to a chart which displays the old refresh data - and so we end up with a chart which tracks this waiting change over the course of a day, or week etc?  This would be really useful to see.

A bit like a stock market chart which keeps track of the daily, or hourly changes of a stock price - this would essentially do the same thing.  

Would really value your feedback on whether this is even possible.  If it is - how on earth would I go about setting this sort of report up??  Many thanks.  Kind regards.

[ppm1]

This is possible, isn't that difficult, but does require several steps. You can create a Power Automate flow to query your current dataset after each hourly refresh, create a csv file with a name that contains date and time, store it somewhere (usually SharePoint), and then combine those files into a new table in your model, parsing the filename into Date and Time columns (the flow also re-trigger the dataset refresh, if needed).  

Pat

[Creative_tree88]

@ppm1 - do you have any examples of this?  Pretty new to Power BI so could do with seeing some examples of how this is applied / works etc.  Many thanks!

[amitchandak]

@Creative_tree88 , if you do not have snapshot at source, you need to consider DAX append method

https://blog.crossjoin.co.uk/2020/04/13/keep-the-existing-data-in-your-power-bi-dataset-and-add-new-...
https://www.thebiccountant.com/2017/01/11/incremental-load-in-powerbi-using-dax-union/