Slow loading of data

Hi all,

I am working on a dashboard that needs a trendline for several months. It is about several thousand devices that poll every 90 seconds. All I need is the maximum value of these devices for each day and put that in an trendline summarized based on a filter/Slicer. It's all in one database.

I first used the normal Power query load al the data and then filter it all accordingly, it  takes about 15 seconds.

2nd attempt I tried an custom SQL statement that only get the maximum value for each day for each device, still around 14 seconds.

Any one got another tip or trick I can use ? 

Thanks in advance 🙂