Hey I created canvas widget using below script but widgets failed to load in 8.4.2 Version

[JLeysens (Jean-Louis Leysens)]

As time passes your datatable sometimes has data other times not (since you are looking at the last 5 minutes based on your query this is probably a smallish sample set).

See this solution for handling a potentially empty datatable:

Handling an empty datatable

Finally figured this one out. I replaced the line: math "mean(percentage)" with: if {rowCount | eq 0} then=0 else={math "mean(percentage)"} If the datatable is not empty, then it returns the average of the "percentage" column, otherwise it returns an "average" value of 0. Now I no longer get the error triangle at runtime of the canvas.

You should be able to prevent the empty datatable from causing issues for your getCell call too (note: getCell defaults to using row 0 if now value is provided, see the docs)