Table of Contents

In this article, we will see 100 PromQL(Prometheus Query Language) MCQs for Interviews and Exams. Prometheus Query Language, commonly known as PromQL, is a powerful and flexible query language specifically designed for the Prometheus monitoring system. Prometheus is an open-source system monitoring and alerting toolkit, widely used for its robust metrics collection, querying capabilities, and alerting features. PromQL plays a crucial role in these functionalities. We will see 100 MCQs related to those roles and all the important functionalities it provides for prometheus monitoring system.

**100 PromQL(Prometheus Query Language) MCQs for Interviews and Exams**

**Also Read:** **50 Apache Kafka Interview Questions and Answers for Beginners**

**1. What is PromQL primarily used for?**

**A. Data backup**

**B. Querying and analyzing time-series data in Prometheus**

**C. Managing user permissions in Prometheus**

**D. Visualizing data in Grafana**

**Ans: B. Querying and analyzing time-series data in Prometheus**

**2. Which of the following is a basic element in PromQL?**

**A. Dashboard**

**B. Metric**

**C. Panel**

**D. Alert**

**Ans: B. Metric**

**3. What does a 'Counter' in PromQL represent?**

**A. A gauge that decreases and increases**

**B. A metric that only increases or resets to zero**

**C. A constant value**

**D. A dynamic query function**

**Ans: B. A metric that only increases or resets to zero**

**4. In PromQL, what operator would you use to select a range of time series data?**

**A. []**

**B. ()**

**C. {}**

**D. <>**

**Answer: A. []**

**5. What is the purpose of the 'sum' function in PromQL?**

**A. To count the number of elements in a series**

**B. To calculate the average value of a series**

**C. To calculate the total sum of a series**

**D. To determine the maximum value of a series**

**Ans: C. To calculate the total sum of a series**

**6. How does PromQL handle missing data in a time series?**

**A. By interpolating values**

**B. By using the last known value**

**C. By skipping the missing data**

**D. By resetting the series**

**Ans: C. By skipping the missing data**

**7. Which keyword in PromQL is used for specifying a time duration?**

**A. DURATION**

**B. PERIOD**

**C. TIME**

**D. FOR**

**Ans: D. FOR**

**8. What does the PromQL 'rate' function compute?**

**A. The count of events in a given time window**

**B. The average value over time**

**C. The per-second average rate of increase of a counter**

**D. The total sum over a specified time period**

**Ans: C. The per-second average rate of increase of a counter**

**9. In PromQL, what does a 'Histogram' typically represent?**

**A. A visual representation of data**

**B. A metric type that samples observations**

**C. A static metric value**

**D. A query function**

**Ans: B. A metric type that samples observations**

**10. What role do labels play in PromQL?**

**A. They organize queries into categories**

**B. They are used for aesthetic purposes**

**C. They identify and group time series data**

**D. They control access to data**

**Ans: C. They identify and group time series data**

**11. Which PromQL function is used to calculate the minimum value of a given range of data?**

**A. min_over_time**

**B. sum_over_time**

**C. avg_over_time**

**D. max_over_time**

**Ans: A. min_over_time**

**12. What is the purpose of the label_replace function in PromQL?**

**A. To delete labels from a metric**

**B. To replace an existing label's value**

**C. To create a new metric with different labels**

**D. To filter data based on label values**

**Ans: B. To replace an existing label's value**

**13. In PromQL, how is the irate function different from the rate function?**

**A. irate calculates the rate over the last two points**

**B. irate calculates the total rate over all points**

**C. irate is used for counters, rate for gauges**

**D. There is no difference**

**Ans: A. irate calculates the rate over the last two points**

**14. What type of data does the histogram_quantile function in PromQL operate on?**

**A. Gauge**

**B. Counter**

**C. Histogram**

**D. Summary**

**Ans: C. Histogram**

**15. Which PromQL operator allows you to perform vector matching on time series data?**

**A. The + operator**

**B. The * operator**

**C. The == operator**

**D. The on operator**

**Ans: D. The on operator**

**16. In PromQL, what is the purpose of using offset in a query?**

**A. To shift the time window of the query**

**B. To add an offset to metric values**

**C. To delay the execution of the query**

**D. To offset labels for grouping**

**Ans: A. To shift the time window of the query**

**17. What does the count function in PromQL return?**

**A. The total sum of all the values in a range vector**

**B. The average value of all points in a range vector**

**C. The number of elements in a range vector**

**D. The maximum value in a range vector**

**Ans: C. The number of elements in a range vector**

**18. Which PromQL function would you use to find the standard deviation of a range of values?**

**A. stddev_over_time**

**B. avg_over_time**

**C. variance_over_time**

**D. sum_over_time**

**Ans: A. stddev_over_time**

**19. What does a vector represent in PromQL?**

**A. A collection of matrices**

**B. A set of time series data at a single point in time**

**C. A database of Prometheus metrics**

**D. A graphical representation of data**

**Ans: B. A set of time series data at a single point in time**

**20. How does the absent function in PromQL work?**

**A. It returns 1 if the vector is empty**

**B. It removes absent values from the result**

**C. It calculates the absolute value of elements**

**D. It checks for non-existent labels**

**Ans: A. It returns 1 if the vector is empty**

**21. What result does the up metric in PromQL typically return?**

**A. The status of the Prometheus server**

**B. The number of active alerts**

**C. The uptime of a monitored service**

**D. The availability status of target instances**

**Ans: D. The availability status of target instances**

**22. Which function in PromQL is used to predict the value of a time series into the future?**

**A. predict_linear**

**B. future_value**

**C. extrapolate**

**D. forecast**

**Ans: A. predict_linear**

**23. In PromQL, how does the changes function operate?**

**A. It calculates the rate of change over a time period**

**B. It counts how many times a series has changed value**

**C. It identifies changes in label values**

**D. It adjusts for changes in metric collection intervals**

**Ans: B. It counts how many times a series has changed value**

**24. What does the increase function in PromQL do?**

**A. Calculates the increase in a counter over a time period**

**B. Increments all values in a series**

**C. Increases the time range of a query**

**D. Scales up the output of a query**

**Ans: A. Calculates the increase in a counter over a time period**

**25. Which of these is a valid PromQL aggregator?**

**A. join**

**B. merge**

**C. sum**

**D. concat**

**Ans: C. sum**

**26. In PromQL, what is the purpose of the without clause?**

**A. To exclude certain metrics from a query**

**B. To remove labels from the result of a query**

**C. To perform a query without a time range**

**D. To negate a query condition**

**Ans: B. To remove labels from the result of a query**

**27. How is the avg_over_time function used in PromQL?**

**A. To calculate the average value of a gauge over time**

**B. To average the time intervals between data points**

**C. To determine the average number of time series in a query**

**D. To compute the overall average value of a counter**

**Ans: A. To calculate the average value of a gauge over time**

**28. What does the holt_winters function in PromQL provide?**

**A. A machine learning model for anomaly detection**

**B. A method for linear regression analysis**

**C. A technique for smoothing time series data**

**D. A tool for historical data comparison**

**Ans: C. A technique for smoothing time series data**

**29. Which PromQL operator is used for vector matching based on label sets?**

**A. and**

**B. or**

**C. unless**

**D. group_left**

**Ans: D. group_left**

**30. What does the quantile_over_time function in PromQL do?**

**A. Calculates the specified quantile of values in a range vector**

**B. Returns the highest value in a time range**

**C. Determines the most frequent value in a series**

**D. Measures the variability of a dataset**

**Ans: A. Calculates the specified quantile of values in a range vector**

**31. Which PromQL function is used to find the difference between the first and last value of a range vector?**

**A. delta**

**B. diff**

**C. range**

**D. spread**

**Ans: A. delta**

**32. What is the role of the vector function in PromQL?**

**A. To convert a scalar to a vector**

**B. To create a vector from a string**

**C. To generate a vector with a single element**

**D. To transform a time series into a vector**

**Ans: A. To convert a scalar to a vector**

**33. How does the sort function affect the results of a PromQL query?**

**A. It orders the results by their label values**

**B. It arranges the output in ascending value order**

**C. It sorts the results based on the time of recording**

**D. It organizes the results in random order**

**Ans: B. It arranges the output in ascending value order**

**34. In PromQL, what does the group function do?**

**A. It aggregates multiple time series into a single series**

**B. It classifies time series based on label values**

**C. It groups results by time intervals**

**D. There is no group function in PromQL**

**Ans: D. There is no group function in PromQL**

**35. What is the primary use of the topk function in PromQL?**

**A. To return the top k results by sample value**

**B. To calculate the sum of the top k values**

**C. To list the top k labels in a series**

**D. To determine the highest k values in a time range**

**Ans: A. To return the top k results by sample value**

**36. How is the floor function used in PromQL?**

**A. To round down sample values to the nearest integer**

**B. To reduce the precision of floating-point values**

**C. To limit the query results to floor values**

**D. To calculate the minimum value of a series**

**Ans: A. To round down sample values to the nearest integer**

**37. In PromQL, what is achieved by using the bool modifier in comparison operators?**

**A. It turns the output into boolean values**

**B. It applies a Boolean logic to the query**

**C. It enhances the query with Boolean algebra**

**D. It converts numeric results into binary format**

**Ans: A. It turns the output into boolean values**

**38. Which PromQL function would you use to get the exact number of instant vectors in a time series?**

**A. count**

**B. count_values**

**C. length**

**D. size**

**Ans: A. count**

**39. What is the result of the time() function in PromQL?**

**A. The total time range of the query**

**B. The current time in Unix epoch seconds**

**C. The execution time of the query**

**D. The time interval between data points**

**Ans: B. The current time in Unix epoch seconds**

**40. How does the reset function in PromQL work?**

**A. It restarts the Prometheus server**

**B. It resets the time series in a query**

**C. It counts the number of counter resets within a time series**

**D. It removes all labels from a time series**

**Ans: C. It counts the number of counter resets within a time series**

**41. What does the PromQL function count_over_time calculate?**

**A. The total count of all values in a range vector**

**B. The number of unique label sets in a range vector**

**C. The average value of a range vector**

**D. The rate of change in a range vector**

**Ans: A. The total count of all values in a range vector**

**42. In PromQL, what is the purpose of the label_join function?**

**A. To concatenate the values of multiple labels into a single label**

**B. To join two different metrics based on a label**

**C. To create a new label from existing metric names**

**D. To filter out labels from a query result**

**Ans: A. To concatenate the values of multiple labels into a single label**

**43. How is the bottomk function used in PromQL?**

**A. To return the bottom k results by sample value**

**B. To calculate the sum of the bottom k values**

**C. To list the bottom k labels in a series**

**D. To determine the lowest k values in a time range**

**Ans: A. To return the bottom k results by sample value**

**44. Which PromQL function is best suited for calculating the average rate of change of a counter over time?**

**A. avg_over_time**

**B. rate**

**C. increase**

**D. delta**

**Ans: B. rate**

**45. In PromQL, what does the ignoring clause do in a query?**

**A. It disregards specific labels while matching series**

**B. It ignores any null or missing values in a series**

**C. It excludes certain metrics from the query**

**D. It skips the specified time range in the query**

**Ans: A. It disregards specific labels while matching series**

**46. What result is returned by the PromQL absent function when a series is present?**

**A. A vector with a single zero**

**B. An empty vector**

**C. A vector with the value '1'**

**D. The original series unmodified**

**Ans: B. An empty vector**

**47. How does the clamp_max function in PromQL operate?**

**A. It sets an upper limit on the query time range**

**B. It caps the values in a series to a maximum value**

**C. It finds the maximum value in a series**

**D. It limits the number of results returned by a query**

**Ans: B. It caps the values in a series to a maximum value**

**48. In PromQL, what does the operator =~ represent?**

**A. Equal to**

**B. Not equal to**

**C. Matches a regular expression**

**D. Does not match a regular expression**

**Ans: C. Matches a regular expression**

**49. What does the PromQL round function do?**

**A. Rounds values in a series to the nearest integer**

**B. Smoothens the peaks in a time series**

**C. Creates a round-robin effect in the series data**

**D. Rounds the time range of a query**

**Ans: A. Rounds values in a series to the nearest integer**

**50. Which PromQL function would be used to get the instantaneous value of a range vector at a given time?**

**A. instant**

**B. value_at_time**

**C. current**

**D. sample**

**Ans: B. value_at_time**

**51. What is the primary use of the or operator in PromQL?**

**A. To perform a logical OR operation between two vectors**

**B. To add two vectors together**

**C. To return the union of two vectors, excluding overlapping elements**

**D. To compare two vectors and return the larger of each pair of elements**

**Ans: C. To return the union of two vectors, excluding overlapping elements**

**52. How does the avg aggregator function in PromQL work?**

**A. It calculates the sum of values in each time series**

**B. It finds the maximum value in each time series**

**C. It computes the average of values in each time series**

**D. It counts the number of elements in each time series**

**Ans: C. It computes the average of values in each time series**

**53. Which function in PromQL is used to calculate the 90th percentile over a range vector?**

**A. quantile(0.9, ...)**

**B. topk(0.9, ...)**

**C. percentile(90, ...)**

**D. p90_over_time(...)**

**Ans: A. quantile(0.9, ...)**

**54. What does the min function in PromQL return?**

**A. The minimum value across a range of time series**

**B. The time series with the minimum value at each instant**

**C. The minimum value of each time series in a vector**

**D. The smallest label set in the query result**

**Ans: A. The minimum value across a range of time series**

**55. In PromQL, what is the unless operator used for?**

**A. To exclude certain time series based on a condition**

**B. To perform subtraction between two vectors**

**C. To return a vector only when another vector is absent**

**D. To create a default value if a query returns no result**

**Ans: C. To return a vector only when another vector is absent**

**56. How is the clamp_min function used in PromQL?**

**A. To set a lower threshold for a query**

**B. To return the minimum value within each time series**

**C. To cap the values in a series at a minimum value**

**D. To limit the number of elements returned in a query**

**Ans: C. To cap the values in a series at a minimum value**

**57. What is the result of using the * operator in PromQL without a joining criterion?**

**A. It multiplies the values of all matching elements**

**B. It returns an error**

**C. It performs a Cartesian product of the two vectors**

**D. It multiplies the values of all elements regardless of matching**

**Ans: C. It performs a Cartesian product of the two vectors**

**58. Which PromQL function is used to calculate the sum of all elements in a range vector?**

**A. total_over_time**

**B. sum_over_time**

**C. accumulate**

**D. aggregate_over_time**

**Ans: B. sum_over_time**

**59. What does the on clause in a PromQL query do?**

**A. Specifies the labels to match on during a vector operation**

**B. Sets the time range for the query**

**C. Indicates the metric on which to perform the query**

**D. Turns on specific query optimizations**

**Ans: A. Specifies the labels to match on during a vector operation**

**60. How is the rate function in PromQL typically used with counters?**

**A. To calculate the total increase of the counter over time**

**B. To determine the per-second average rate of increase**

**C. To find the instantaneous rate of change**

**D. To measure the frequency of counter resets**

**Ans: B. To determine the per-second average rate of increase**

**61. In PromQL, what is the function of the histogram_quantile function?**

**A. To create a histogram from a set of data**

**B. To calculate a quantile value from a histogram**

**C. To convert a histogram into a time series**

**D. To aggregate multiple histograms into one**

**Ans: B. To calculate a quantile value from a histogram**

**62. How does the sum without function operate in PromQL?**

**A. It sums up values while ignoring specified labels**

**B. It adds values without any labels**

**C. It returns the sum of values excluding the minimum and maximum**

**D. It sums up values without time constraints**

**Ans: A. It sums up values while ignoring specified labels**

**63. Which PromQL function is used for alerting based on the sudden change in a metric?**

**A. changes**

**B. delta**

**C. deriv**

**D. predict_linear**

**Ans: C. deriv**

**64. What does the idelta function in PromQL compute?**

**A. The integral of a time series**

**B. The instant rate of change between the last two samples**

**C. The average delta over a time period**

**D. The total change over the entire time series**

**Ans: B. The instant rate of change between the last two samples**

**65. In PromQL, what does the count by function do?**

**A. It counts the number of unique values for each label**

**B. It groups the count by a set of labels**

**C. It returns the total count of elements in a time series**

**D. It counts the number of labels in a query**

**Ans: B. It groups the count by a set of labels**

**66. How is the max_over_time function used in PromQL?**

**A. To calculate the maximum value over a specified time period**

**B. To find the time when the maximum value occurred**

**C. To determine the overall maximum value of all time series**

**D. To limit the time range of a query to its maximum value**

**Ans: A. To calculate the maximum value over a specified time period**

**67. What is the result of the avg by operation in PromQL?**

**A. It averages the values of each series by label**

**B. It calculates the global average across all series**

**C. It averages the values within each series**

**D. It returns the average number of labels**

**Ans: A. It averages the values of each series by label**

**68. Which PromQL operator is used to exclude some labels from the result?**

**A. without**

**B. ignore**

**C. excluding**

**D. omit**

**Ans: A. without**

**69. In PromQL, how does the rate function differ from the delta function?**

**A. rate calculates a per-second average rate, while delta calculates the absolute change**

**B. rate shows total increase, delta shows per-second increase**

**C. There is no difference between the two functions**

**D. delta is used for gauges, rate for counters**

**Ans: A. rate calculates a per-second average rate, while delta calculates the absolute change**

**70. What does the group_left modifier do in PromQL?**

**A. It groups the results based on the leftmost label**

**B. It is used in many-to-one and one-to-many matching**

**C. It excludes the leftmost label in a query**

**D. It shifts the time series data to the left**

**Ans: B. It is used in many-to-one and one-to-many matching**

**71. What is the purpose of the sort_desc function in PromQL?**

**A. To arrange query results in descending order based on their values**

**B. To sort labels in descending alphabetical order**

**C. To reverse the time range of a query**

**D. To calculate the descending cumulative sum of a series**

**Ans: A. To arrange query results in descending order based on their values**

**72. In PromQL, what does the irate function specifically measure?**

**A. The rate of increase over the longest possible time period**

**B. The instant rate of increase based on the last two data points**

**C. The average rate of increase over the entire time series**

**D. The predicted rate of increase for future values**

**Ans: B. The instant rate of increase based on the last two data points**

**73. How is the label_match function used in PromQL?**

**A. To find series that match a given label expression**

**B. To replace the labels of a series**

**C. To add new labels to a series**

**D. There is no label_match function in PromQL**

**Ans: D. There is no label_match function in PromQL**

**74. What does the year() function return in PromQL?**

**A. The year from each timestamp in a time series**

**B. The number of years since the Unix epoch**

**C. The current year**

**D. The year of the oldest data point in a series**

**Ans: C. The current year**

**75. In PromQL, what does the vector(scalar) function do?**

**A. It converts a scalar value to a vector**

**B. It multiplies a vector by a scalar**

**C. It extracts the scalar value from a vector**

**D. It creates a vector with elements equal to the scalar value**

**Ans: A. It converts a scalar value to a vector**

**76. How does the time() function in PromQL work?**

**A. It returns the current time in Unix time format**

**B. It calculates the total time span of the data in a query**

**C. It converts a time series into a scalar timestamp**

**D. It measures the time taken to execute a query**

**Ans: A. It returns the current time in Unix time format**

**77. What is the use of count_values in PromQL?**

**A. To count the number of unique values in a series**

**B. To count the occurrences of each value in a series**

**C. To sum up the values in a series**

**D. To find the most frequent value in a series**

**Ans: B. To count the occurrences of each value in a series**

**78. In PromQL, what is the result of the sum by operation?**

**A. It sums the values of each series and groups the result by label**

**B. It sums up all values in the query regardless of labels**

**C. It calculates the sum of a series and then applies labels**

**D. It returns the sum of all labels in a series**

**Ans: A. It sums the values of each series and groups the result by label**

**79. How does the month() function in PromQL operate?**

**A. It extracts the month from each timestamp in a series**

**B. It returns the number of months since the Unix epoch**

**C. It gives the current month**

**D. It calculates the average values for each month**

**Ans: C. It gives the current month**

**80. What does the PromQL operator != accomplish?**

**A. It selects elements that are not equal in value**

**B. It finds labels that do not match**

**C. It negates a boolean expression**

**D. It excludes specific metrics from the results**

**Ans: A. It selects elements that are not equal in value**

**81. Which PromQL function is used to calculate the current memory usage as a percentage of the total available memory?**

**A. avg_over_time**

**B. sum**

**C. rate**

**D. percentage**

**Ans: D. percentage**

**82. In PromQL, what does the count_scalar function do?**

**A. It converts a count into a scalar value**

**B. It counts the number of scalar values in a vector**

**C. It creates a scalar from the count of elements in a vector**

**D. There is no count_scalar function in PromQL**

**Ans: D. There is no count_scalar function in PromQL**

**83. How is the exp function used in PromQL?**

**A. To calculate the exponential growth of a series**

**B. To expand the range of a query**

**C. To express a series in exponential format**

**D. To exponentiate each value in a series**

**Ans: D. To exponentiate each value in a series**

**84. What does the offset modifier do in a PromQL query?**

**A. It shifts the time series back by a specified duration**

**B. It adds a fixed value to each data point**

**C. It adjusts the starting point of the query**

**D. It offsets the value of labels in a query**

**Ans: A. It shifts the time series back by a specified duration**

**85. In PromQL, what is the result of the ln function?**

**A. It calculates the natural logarithm of each value in a series**

**B. It returns a linear interpolation of a time series**

**C. It links two time series together**

**D. It finds the line number of each data point**

**Ans: A. It calculates the natural logarithm of each value in a series**

**86. How does the quantile function work in PromQL?**

**A. It determines the specified quantile across input vectors**

**B. It creates a quantile series from a single vector**

**C. It quantifies the difference between two vectors**

**D. It returns a vector containing all quantiles**

**Ans: A. It determines the specified quantile across input vectors**

**87. What is the purpose of the stddev function in PromQL?**

**A. To standardize the deviance of a time series**

**B. To calculate the standard deviation within each time series**

**C. To find deviations from the standard values**

**D. To normalize the standard labels in a query**

**Ans: B. To calculate the standard deviation within each time series**

**88. In PromQL, how is the year function typically used?**

**A. To filter data by year**

**B. To extract the year from a timestamp**

**C. To calculate the yearly rate of change**

**D. To group data by year**

**Ans: B. To extract the year from a timestamp**

**89. What does the avg without function do in PromQL?**

**A. It averages values while ignoring specified labels**

**B. It computes the average without considering time range**

**C. It calculates the average excluding minimum and maximum values**

**D. It averages values without any labels**

**Ans: A. It averages values while ignoring specified labels**

**90. In PromQL, what does the predict_linear function estimate?**

**A. The future value of a time series based on past trends**

**B. Linear correlations between two time series**

**C. The linear progression of label values**

**D. The linear increase rate of a counter**

**Ans: A. The future value of a time series based on past trends**

**91. What is the primary function of the increase function in PromQL?**

**A. To calculate the rate of increase of a counter over a time range**

**B. To sum the increases in a time series**

**C. To increment all values in a vector**

**D. To track the cumulative increase of a gauge**

**Ans: B. To sum the increases in a time series**

**92. In PromQL, how is the sum by (label) function used?**

**A. To sum up the values in each series, grouped by the specified label**

**B. To add values to a series based on label criteria**

**C. To sum all values across different series without grouping**

**D. To add a new label with the sum of values to each series**

**Ans: A. To sum up the values in each series, grouped by the specified label**

**93. Which function in PromQL is best suited for finding the highest value of a metric over a specified time range?**

**A. max**

**B. max_over_time**

**C. topk**

**D. highest**

**Ans: B. max_over_time**

**94. How does the absent function operate in PromQL?**

**A. It removes absent values from a series**

**B. It returns a vector if the input vector is empty**

**C. It checks for the absence of a specified label**

**D. It creates an empty vector from a non-empty input**

**Ans: B. It returns a vector if the input vector is empty**

**95. What does the histogram_quantile function compute in PromQL?**

**A. The distribution of values in a histogram**

**B. The average value of a histogram**

**C. A quantile value from a histogram**

**D. The sum of all buckets in a histogram**

**Ans: C) A quantile value from a histogram**

**96. In PromQL, what is the purpose of the rate function when used with counter metrics?**

**A. To calculate the total increase of the counter**

**B. To find the average value of the counter**

**C. To determine the per-second average rate of increase**

**D. To measure the instantaneous rate of change**

**Ans: C. To determine the per-second average rate of increase**

**97. How is the floor function used in PromQL?**

**A. To reduce the precision of floating-point values**

**B. To round down each value in a series to the nearest integer**

**C. To find the minimum value of a series**

**D. To set a lower limit for query results**

**Ans: B. To round down each value in a series to the nearest integer**

**98. What result does the group_left modifier yield in PromQL vector matching?**

**A. It groups the leftmost labels in a query**

**B. It is used in many-to-one and one-to-many matches**

**C. It excludes the leftmost label in vector matching**

**D. It performs a left join of two vectors**

**Ans: B. It is used in many-to-one and one-to-many matches**

**99. In PromQL, how does the count_over_time function operate?**

**A. It counts the number of unique values over time**

**B. It sums up the count of all elements in a range vector**

**C. It counts the occurrences of a specific value over time**

**D. It calculates the rate of count increase over time**

**Ans: B) It sums up the count of all elements in a range vector**

**100. In PromQL, what does the vector function do?**

**A. It converts a scalar or string to a vector**

**B. It creates a vector from a time series**

**C. It transforms a range vector into an instant vector**

**D. It generates a vector with all elements set to a specific value**

**Ans: A. It converts a scalar or string to a vector**