Hi, I have time series data of temperatures from x10 different sensors, and am displaying the “current” value using a Bar Gauge.
The sensors should get a new value roughly every hour, but I would like some way to show if the sensor has failed (e.g. hasn’t had any data for let’s say 1 day). The problem is that data is always being displayed, no matter how old it is (as expected, because I am selecting LAST):
Idea (so you need to play and develop it): create A query which doesn’t have timefilter - that will have all timeseries - all rooms, value doesn’t matter.
Create query B with time filter e. g. last hour
Use tranformations on the Grafana level:
join A with B by room name
organize - hide unwanted columns
Use only B value in the final result, you can replace text no data with Not available for last hour - it depends if this option is available in used panel type.
How one should understand what doesn’t work? As I said that’s idea. Play, try, improve it until you have desired result. Don’t try to achieve everything in one go. Step by step. First you need data in right format, so don’t focus on visualization - just use table panel, where you will have room and value/no data.
Not every value (metric value), but every tag value (all friendly names).
Yes, it will be inefficient, but you have user on other side with requirement “I WANT this”. So it’s up to you what do you prioritise when used query language doesn’t support it directly. You can also hardcode that list, but that also has pros and cos. You need to decide what you can accept and what is not acceptable.
I don’t know. I gave you the idea only based on my professional experience. Please don’t expect from me that I spent hours just to develop solution to fix your problem for free. It is opinionated idea and you may find that’s non sense idea. Then you should to find better solution for you.