Showing the delta of a value

Hi there!
I’m currently installing some self built smart meters in my house (water, gas and power) that provide their measurements via MQTT. For the visualization I chose Grafana.

Showing the absolute values of each smart meter in Grafana is of course easy. But what I haven’t figured out yet is how to visualize the deltas. E.g. I would like to have a bar graph that shows the power consumption for the last week grouped by day. Or the water consumption of a whole year grouped by month.

Since the meters are always counting up, it would suffice to subtract the max and min values of each day/week/month/year to get the delta in that timespan. This could then be done multiple times to get a bar graph with multiple days/weeks/months.

Is this possible with InfluxDB/Grafana? If so, how?
Or shoukd I choose a different database?

Use DIFFERENCE() function. IMHO DERIVATE() will be better for your case - you want to show daily rate.

Doc: https://docs.influxdata.com/influxdb/v1.5/query_language/functions/

Awesome. This tool just keeps getting better and better :grinning: