Alerts in AWS Managed Grafana

Grafana Alerting
1

I have an Amazon Timestream Database which I can use in Dashboards without any problems. However when trying to set up an Alert I always get a strange error message:

“Failed to evaluate queries and expressions: input data must be a wide series but got type long (input refid)”

My timestream database looks like this
header:
DevEUI measure_name time measure_value::bigint measure_value::varchar
sample data:
A84041B841867DF4 distanz_mm 2024-03-27 10:34:24.336000000 1808 -
00404C4AADED14D4 distanz_mm 2024-03-27 10:30:05.960000000 2209 -

Using the following SQL statement creating the alert would then lead to the above error.

SELECT * FROM $__database.$__table WHERE measure_name=‘distanz_mm’ AND DevEUI=‘00404C4AADED14D4’

The strange thing is that I can use the same SQL statement in the Explore function or in dashboards and it will execute without errors.

Any help on this is highly appreciated.
Martin

2

OK so it seems the SQL query needs to be adjusted a bit.
Only time and measure_value::bigint needs to be selected:

SELECT time, measure_value::bigint FROM $__database.$__table WHERE measure_name=‘distanz_mm’ AND …

With this SQL query the alerts do work. Still not sure about the reason for the error message in the previous post though.