Hi all.
I’m using Grafana v10.4.2 (22809dea50).
I have a panel showing a series of soil moisture values along with permanent wilting point, saturation point, field capacity and some other values. There is a soil moisture value every 5 minutes but Permanent Wilting Point etc. are rarely changed.
I wanted to reduce the data packet size by eliminating the long series of identical values for permanent wilting point and those other items so broke it down into two queries:
Query A
time1, time2, time3… time99
soil_moisture1, soil_moisture2, soil_moisture3… soil_moisture99
Query B
time1, time99
permanent_wilting_point1, permanent_wilting_point99
…
I use the join transformation to make one data set, and in the panel use the interpolation options to make the line bridge the gap between permanent_wilting_point1 and permanent_wilting_point99 and so on.
This works really well in showing the line graph, but the tool tip shows nothing for permanent wilting point etc over that long gap. Is there some way to have the tooltip show the most recent non-null value, or alternatively is there a transformation that I could use to replicate the most recent non-null value over subsequent null values?
This is how the tool tips appear at time1 and a time midway across the panel - note the blank values against Permanent Wilting Point etc…:
And this is the merged data set in Table View:
Many thanks.
Beau.