I have a a prometheus metric with dynamic labels indicating the revision of some data source. The records of the versions_info data source look like this:

{instance="loogle.lean-lang.org:80", job="loogle", loogle="36c07149f33f122a5498369409eafe8c8e7f514b", mathlib="df0b4dd7c1ca19a2861ca6ec1bd63851cb6037e9"}

How would I create a Grafana alert that fires when this metric did not change in the last 24h?

I tried

changes(versions_info[24h]) == 0

but it shows up in in the “Table” as one row per label and a value of 0, as if it is counting the changes separately for each set of label values.

I wonder if I want some way of saying “give me the value of this label for each sample”:

changes(versions_info[24h].mathlib) == 0