PCA (Prometheus Certified Associate) sample exam question with answer 18

Question:
Which of the following best describes the deriv() function in PromQL?

1. Calculates the per-second rate of increase of a counter metric
2. Calculates the per-second rate of change of a gauge metric
3. Calculates the average rate of increase of a counter metric over a time range
4. Calculates the rate of change of a gauge metric at a specific point in time

Answer:
B - The deriv() function calculates the per-second rate of change of a gauge metric.
This is useful for seeing how quickly a gauge metric is changing over time