The strcat_array function in Axiom Processing Language (APL) allows you to concatenate the elements of an array into a single string, with an optional delimiter separating each element. This function is useful when you need to transform a set of values into a readable or exportable format, such as combining multiple log entries, tracing IDs, or security alerts into a single output for further analysis or reporting.

For users of other query languages

If you come from other query languages, this section explains how to adjust your existing queries to achieve the same results in APL.

Usage

Syntax

strcat_array(array, delimiter)

Parameters

ParameterTypeDescription
arraydynamicThe array of values to concatenate.
delimiterstringThe string used to separate each element in the concatenated result. Optional. Defaults to an empty string if not specified.

Returns

A single concatenated string with the array’s elements separated by the specified delimiter.

Use case example

You can use strcat_array to combine HTTP methods and URLs for a quick summary of unique request paths.

Query

['sample-http-logs']
| take 50
| extend combined_requests = strcat_delim(' ', method, uri)
| summarize requests_list = make_list(combined_requests)
| extend paths = strcat_array(requests_list, ', ')

Run in Playground

Output

paths
GET /index, POST /submit, GET /about

This query summarizes unique HTTP method and URL combinations into a single, readable string.