PCAUpdated 8d ago · Aug 28, 2026
PCA: Prometheus Certified Associate
60 questions across 1 topics, with suggested answers, explanations where available, and imported community discussion. The first 6 questions are free to preview.
Topics
| # | Topic | Questions | Free |
|---|---|---|---|
| 1 | PromQL | 60 | 6 |
Preview
6 of 60 accessibleQuestion 1 · PromQL Open
Which PromQL expression returns the total of every `node_memory_MemAvailable_bytes` metric value from 10 minutes earlier?
Answer: C
In PromQL, `offset` shifts an instant-vector selector back in time and must immediately follow that selector. Thus, `node_memory_MemAvailable_bytes offset 10m` retrieves the values from 10 minutes ago, and `sum(...)` totals them across all matching series.
**Learn more:** [Prometheus Querying Basics — Offset modifier](https://prometheus.io/docs/prometheus/latest/querying/basics/)
Question 2 · PromQL Open
Given the metric `prometheus_tsdb_lowest_timestamp_seconds`, how can you determine the month to which the lowest timestamp in your Prometheus TSDB belongs?
Answer: A
PromQL’s `month()` function returns the calendar month, in UTC, for each input timestamp. Applying it to `prometheus_tsdb_lowest_timestamp_seconds` extracts the month represented by that metric’s Unix timestamp.
**Learn more:** [Prometheus query functions: month()](https://prometheus.io/docs/prometheus/latest/querying/functions/#month)
Question 3 · PromQL Open
Which of the following is an invalid `@` modifier expression?
Answer: B
The `@` modifier must immediately follow an instant-vector or range-vector selector. It cannot be applied to the result of `sum(...)`; the timestamp modifier belongs inside the aggregation, attached to `http_requests_total{method="GET"}`. `start()` and `end()` are valid special values for this modifier.
**Learn more:** [Prometheus Querying Basics: @ modifier](https://prometheus.io/docs/prometheus/latest/querying/basics/)