Understanding KQL Functions

Correct Answer: C

Reference:

Kusto Query Language (KQL) is a powerful query language used for querying large amounts of structured or semi-structured data. KQL includes a variety of built-in functions that can be used to manipulate and analyze data, as well as user-defined functions that can be created to perform custom operations on data. A KQL function is a user-defined function that allows users to create custom functions that can be called in KQL queries.

Option A is incorrect because KQL functions can be created and modified by users to meet specific needs. Option B is incorrect because KQL functions are not procedural calls made by KQL to an external processor. Option D is incorrect because KQL functions do not act as black boxes for data processing. Option E is incorrect because KQL does not allow other coding languages to be used as embedded functions.

Option C is the correct answer. A KQL function is a query that a user creates, saves, and assigns an alias to call it by. This function can then be used repeatedly in other KQL queries to perform the same operation on different data sets. For example, a user might create a KQL function that calculates the average response time for a specific set of API requests. The user can then assign an alias to the function, such as "CalcAvgResponseTime," and call it in future queries by using the alias. This helps to simplify and standardize the KQL queries, making them easier to write, read, and maintain.