Observability · Flashcard
What does http_requests_total return with no brackets?
- AOne sample per matching series — an instant vector
- BEvery sample — the last five minutes of each series
- COne number — the total across every matching series
- DThe names alone — the series come back without values
Why this is the answer
A bare selector evaluates to an instant vector: the most recent sample for each matching series, taken from within the lookback window. Returning every sample in a window needs a range selector such as [5m], summing across series needs sum(), and values always come back with the series.
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