Purging stale data from charts

[burlmd]

Hello everyone,

I am having an issue understanding how data gets purged from charts in a streaming analytics to power bi setup.  I have a bar chart that displays the count of trips that are late by 15+ minutes, 30+, 45+, etc... (think delivery driver).  With streaming analytics, I am able to process messages from an event hub and send the results to the power bi bar chart.  My query does a group by on the trip id and when I test my query it only ever produces one row per trip, which is what I want.  However, over time, I notice the bar chart is holding on to the result of each past query.  The net effect is I have a bar chart displaying trip A is 10 min late, then trip A is 12 min late, and then trip A is 14 min late.  What I want to see is just that trip A is 14 min late.

How can I purge (or update) existing data in power bi via streaming analytics?

Thanks for the help!

Mark

[AlexChen]

Hi,

Even Power BI can generate dataset for streaming data, it’s still not supported to purge the stream data and keep the latest only.

In this scenario, since you want to get the max last minutes, you can change the aggregation type for the late minutes field on visual level.

Best Regards

Alex

[burlmd]

In my scenario, the driver could potentially make up time between stops, so I believe I will need to add a timestamp with each data record and only display the latest record for a given driver/trip. 

Thanks for the ideas.  I'll let you know if I'm able to get this to work. 

[samdthompson]

Hi, to me that looks like a problem with the relationships. Can you post a picture of the relationship diagram.

//if this is a solution please mark as such

[burlmd]

Hmm, I don't see how to view the relationship diagram in the online version of power bi.  Is there something I'm missing?  I see the relationships tab in the power bi desktop app, but I'm only using the online version right now.

This leads to another issue, which is I would like to be able to define my dataset and all associated charts, upload that to the online power bi, and then have streaming analytics just fill the dataset.  Is this possible?

[samdthompson]

Hi, you can not look at relationships in the online version. Yes that is possible if you have a gateway up and running.