Prometheus
prometheus.io › docs › prometheus › latest › querying › functions
Query functions | Prometheus
The info function is an experiment to improve UX around including labels from info metrics . The behavior of this function may change in future versions of Prometheus, including its removal from PromQL.
Chronosphere
docs.chronosphere.io › investigate › querying › promql › apply-functions
Applying PromQL functions - Chronosphere Documentation
July 9, 2026 - PromQL functions perform calculations with and on your metrics data, letting you complete complex processing with pre-built operations. Each function takes different arguments, but typically at minimum, an instant or range vector.
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PromQL Tutorial: A COMPLETE Guide to Prometheus Queries - YouTube
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Querying metrics w/ PromQL - YouTube
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Understanding Counter Rates and Increases in PromQL | Reset Handling, ...
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PromQL (Prometheus Query Language) - YouTube
13:58
PromQL Data Selection Explained | Selectors, Lookback Delta, Offsets, ...
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Prometheus Functions Changes - deriv(), predict_linear | Prometheus ...
What is PromQL?
PromQL (Prometheus Query Language) is the query language built into Prometheus for selecting, filtering, and aggregating time series data. You use it to write expressions that power dashboards, alerts, and ad-hoc metric analysis.
last9.io
last9.io › blog › promql-cheat-sheet
PromQL Cheat Sheet: Queries, Functions, and Labels | Last9
How do I filter by label values in PromQL?
Use curly brace selectors: http_requests_total{job="api", status="500"} for exact matches, {status=~"5.."} for regex matches, and {status!="200"} to exclude a value. Multiple label filters combine with AND logic.
last9.io
last9.io › blog › promql-cheat-sheet
PromQL Cheat Sheet: Queries, Functions, and Labels | Last9
How do I find the top N series by a metric in PromQL?
Use topk(N, expr). For example, topk(5, sum(rate(http_requests_total[5m])) by (service)) returns the 5 services with the highest request rate. Use bottomk() for the lowest values.
last9.io
last9.io › blog › promql-cheat-sheet
PromQL Cheat Sheet: Queries, Functions, and Labels | Last9
Prometheus
prometheus.io › docs › prometheus › latest › querying › basics
Querying basics | Prometheus
Both float samples and histogram ... writing PromQL queries. (By convention, time series containing float counters have a name ending on _total to help with the distinction.) Since histogram samples “know” their counter or gauge flavor, this allows reliable warnings about mismatched operations. For example, applying the rate function to gauge floats ...
VictoriaMetrics
victoriametrics.com › blog › prometheus monitoring: functions, subqueries, operators, and modifiers
Prometheus Monitoring: Functions, Subqueries, Operators, and Modifiers
April 25, 2025 - This function looks at all data points collected over the past 3 minutes and returns the highest value to represent those samples. ... In the example above, max_over_time is evaluated at every 5-minute step between 00:10 and 00:30. Each time, it looks back over the previous 3 minutes, collects the samples, and returns the maximum value found in that range. PromQL and MetricsQL both support many rollup functions.
BytePlus
docs.byteplus.com › en › docs › vmp › Basic-PromQL-functions
PromQL common functions--Vital Managed Service for Prometheus-Byteplus
August 19, 2025 - PromQL common functions · Billing · Billing overview · Billing methods · Pay-as-you-go · Package · Package Overview · Purchasing packages · Viewing Packages · Renew Package · Canceling packages and changing package specifications · Price calculator ·
Medium
valyala.medium.com › promql-tutorial-for-beginners-9ab455142085
PromQL tutorial for beginners and humans | by Aliaksandr Valialkin | Medium
September 15, 2023 - VictoriaMetrics extends these functions with more convenient label manipulation functions: label_set — sets additional labels to time series · label_del — deletes the given labels from time series · label_keep — deletes all the labels from time series except the given labels · label_copy — copies label values to another labels ... Sometimes it is necessary to return multiple results from a single PromQL query.
Last9
last9.io › blog › prometheus-functions
Prometheus Functions: How to Make the Most of Your Metrics | Last9
February 28, 2025 - The resets() function helps you identify when this happens: ... This returns the number of counter resets within the last hour, which can be a useful indicator of service stability. To detect sudden changes in rates, you can compare the short-term rate to a longer-term average: ... This alerts when the 5-minute rate differs from the 1-hour rate by more than 30%, indicating a significant change in traffic patterns. PromQL supports powerful label matching techniques that let you zero in on exactly the metrics you care about:
Compile N Run
compilenrun.com › prometheus tutorial › promql (prometheus query language) › promql functions
PromQL Functions | Compile N Run
Use irate for fast-changing counters or when you need to see rapid changes. Use increase when you want the absolute increase rather than a per-second rate. PromQL offers various mathematical functions to transform your data.
Promlabs
promlabs.com › promql-cheat-sheet
PromLabs | PromQL Cheat Sheet
See all available xxx_over_time() aggregation functions. Get the Unix time in seconds at each resolution step: ... Calculate the 5-minute-averaged rate over a 1-hour period, at the default subquery resolution (= global rule evaluation interval): rate(demo_api_request_duration_seconds_count[5m])[1h:] ... Want to learn more? Check out our self-paced in-depth PromQL training by the creator of PromQL.