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How does PromQL handle operator precedence between arithmetic operators like multiplication (*) and addition (+)?
2Which selector syntax correctly matches all time series where the environment label does NOT equal production?
3An administrator wants to aggregate CPU usage across all nodes, keeping the instance label while summing the values. Which aggregation clause should be used?
4When performing a vector-to-vector binary operation between two instant vectors of different label sets, which modifier allows matching on a subset of common labels?
5An operator needs to query the current, un-extrapolated rate of increase per second over the last 5 minutes for a counter metric named http_requests_total. Which function should they use?
6A user executes an instant query for a metric without providing a range vector. What type of vector is returned by default?
7You need to calculate the 99th percentile HTTP request latency from a Prometheus histogram named http_request_duration_seconds. Which function is correct?
8An engineer needs to determine the total absolute increase in disk space consumed over the last 3 hours using a gauge metric node_disk_bytes_used. Which function is appropriate?
9Which PromQL aggregator should be used to count the total number of active time series matching a selector?
10Which label matcher operator is used for exact equality in PromQL selectors?
11You are joining an instant vector of application versions with an instant vector of metrics using a many-to-one relationship. The application version vector has more labels than the metric vector. Which keyword must be appended to the matching modifier to include labels from the 'many' side?
12A Prometheus alert expression uses rate(http_requests_total[5m]) > 10. During a service restart, counter resets occur. How does the rate() function account for these counter resets?
13Which regular expression matcher selects all time series where the status label begins with the digit 5?
14You want to find the maximum value of a gauge metric across all instances over a 1-hour sliding window. Which function accomplishes this?
15What is the primary difference between an instant vector and a range vector in PromQL?
16You need to calculate the per-second rate of increase of http_requests_total over a 1-minute window. Why is using a 1-minute range window generally discouraged in production?
17An operator writes the query sum(rate(http_requests_total[5m])) without any aggregation clauses. What is the output format?
18What is the behavior of the clamp_max() function when applied to an instant vector?
19When writing a query with arithmetic operators, how does PromQL handle vector matching when both vectors have the exact same label sets?
20Which function evaluates the predictable linear extrapolation of a gauge metric over time to predict future values?
21You need to perform a binary operation between two vectors where the left vector has labels {job="api", instance="a"} and the right vector has labels {job="api"}. You want to match them using the job label while retaining the instance label from the left side. Which modifier configuration is correct?
22An engineer executes topk(3, http_requests_total). What happens if there are fewer than 3 time series matching the selector?
23How does Prometheus handle subqueries embedded within an instant query, such as rate(http_requests_total[5m])[30m:1m]?
24When evaluating a rule with offset, such as http_requests_total offset 1h, what exact time does Prometheus query?
25Which TWO of the following are valid metric types natively supported by Prometheus? (Choose TWO)
26Which TWO of the following statements about PromQL label matchers are correct? (Choose TWO)
27Which THREE of the following functions are specifically designed to be used with range vectors? (Choose THREE)
28Which TWO of the following conditions will cause the rate() function to return NaN or empty results? (Choose TWO)
29Which THREE of the following modifiers or keywords are used in PromQL binary vector matching? (Choose THREE)
30Which THREE of the following are valid aggregation operators in PromQL? (Choose THREE)
31An operator writes a query to calculate error percentage: sum(rate(errors[5m])) / sum(rate(total[5m])) * 100. What happens if the denominator evaluates to zero or has no matching time series?
32What is the purpose of the instant vector selector syntax http_requests_total{job="api-server"}?
33Which function should be used to smooth out short-term fluctuations in a gauge metric by calculating the rolling average over a 10-minute window?
34You are troubleshooting a query and notice that label_replace is being used. What is the primary function of label_replace(v, dst_label, replacement, src_label, regex)?
35When evaluating a histogram metric, what does the special pseudo-label le represent in bucket time series?
36An operator needs to find the rate of change of a counter using deriv(). Why is this considered a bad practice in Prometheus?
37Which THREE of the following are valid set operators in PromQL for combining instant vectors? (Choose THREE)
38Which operator has higher precedence in PromQL: exponential (^), multiplication (*), or addition (+)?
39Which TWO of the following statements regarding native histograms in Prometheus are correct? (Choose TWO)
40A Prometheus administrator wants to query the current value of the metric 'http_requests_total'. Which of the following PromQL expressions should be used?
41Which PromQL function is specifically designed to calculate the per-second average rate of increase of a time series over a given range vector?
42You are monitoring a counter metric 'errors_total' and need to calculate the total number of errors that occurred over the last 1 hour. Which function is most appropriate?
43When evaluating a PromQL query involving arithmetic operators, such as 'vector1 + vector2 * vector3', which operator has the highest precedence?
44You are joining an instant vector of application metrics with a static configuration instant vector containing target metadata using 'on(instance) group_right'. What does the 'group_right' modifier achieve?
45You need to calculate the 99th percentile of request latency across all instances using a Prometheus histogram metric 'http_request_duration_seconds_bucket'. Which function and setup is correct?
46A Prometheus selector includes a negative regex match for environment names: 'environment!="staging"'. Which selector operator achieves this using regular expressions instead of exact matching?
47When writing a PromQL query involving a vector and a scalar, such as 'node_memory_free_bytes / (1024 * 1024)', how does Prometheus handle label matching?
48You are joining two vectors where the left vector has labels {job="api", instance="host1"} and the right vector has labels {job="api", region="us-east"}. You use the query 'vector_a + ignoring(instance, region) vector_b'. What does the 'ignoring' modifier do?
49Which of the following selectors matches metric names that start with 'http_'?
50What is the primary operational difference between the 'rate()' and 'irate()' functions in PromQL?
51Which function would you use to find the maximum value of a gauge metric 'node_cpu_load' over the past 30 minutes?
52You need to calculate the ratio of successful HTTP requests (status 200) to total HTTP requests. Both metrics are counters named 'http_requests_total'. How do you construct this query to ensure proper label matching between status='200' and total requests?
53When executing a subquery in PromQL, such as 'max_over_time(rate(http_request_total[5m])[30m:1m])', what does the resolution parameter ('1m') specify?
54You are using the 'predict_linear()' function to forecast disk space exhaustion based on the metric 'node_filesystem_free_bytes'. What type of input data does predict_linear require?
55You want to find the top 3 jobs with the highest CPU usage using the metric 'process_cpu_seconds_total'. Which PromQL query structure is correct?
56Which TWO of the following are valid data types returned by PromQL queries? (Choose two)
57Which TWO of the following label matching operators are supported in Prometheus label selectors? (Choose two)
58Which THREE of the following functions can be used with counter metrics to calculate rates or increases? (Choose three)
59When performing vector matching between two vectors of different cardinalities, which THREE vector matching modifiers can be used? (Choose three)
60Which THREE built-in functions in PromQL are designed specifically to analyze changes over time for gauge metrics? (Choose three)
61Which THREE aggregation operators in PromQL support the 'by' and 'without' clause modifiers? (Choose three)
62Which TWO of the following statements regarding PromQL subqueries are correct? (Choose two)
63Which TWO of the following are valid ways to modify or add labels to time series in PromQL? (Choose two)
64What is the result of applying a range selector like [5m] to a gauge metric?
65You need to calculate the per-second rate of increase for a counter metric over the last 10 minutes. Which function is most appropriate?
66Which operator has the highest precedence in PromQL?
67When calculating the 95th percentile from a histogram, why is histogram_quantile(0.95, sum(rate(http_duration_seconds_bucket[5m])) by (le)) the recommended pattern?
68What is the purpose of the 'offset' modifier in a PromQL query?
69Which aggregation operator would you use to calculate the total sum of a metric across all instances?
70When using 'irate', what is the impact of choosing a range vector that is too small (e.g., [10s])?
71What is the difference between 'count' and 'count_values'?
72If you perform 'A / B' where A and B have different sets of labels, what happens?
73When should you use the 'absent()' function?
74Which operator performs a logical 'not' on a comparison?
75Which function is best suited for identifying the 'top 5' instances with the highest value for a specific metric?
76Which TWO of the following are valid aggregation operators in PromQL?
77Which TWO of the following statements about 'rate' vs 'irate' are correct?
78Which TWO of the following are true regarding instant vectors?
79Which THREE of the following are valid time-range units in PromQL?
80Which THREE of the following are valid label matchers?
81Which THREE of the following are valid ways to modify a binary operation join?
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