pack_array

This page explains how to use the pack_array function in APL.

The pack_array function in APL creates an array from individual values or expressions. You can use this function to group related data into a single field, which can simplify handling and querying of data collections. It is especially useful when working with nested data structures or aggregating data into arrays for further processing.

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.

Splunk SPL users

In Splunk SPL, you typically use functions like mvappend to create multi-value fields. In APL, the pack_array function serves a similar purpose by combining values into an array.

Splunk example

| eval array_field = mvappend(value1, value2, value3)

| extend array_field = pack_array(value1, value2, value3)

ANSI SQL users

In ANSI SQL, arrays are often constructed using functions like ARRAY. The pack_array function in APL performs a similar operation, creating an array from specified values.

SQL example

SELECT ARRAY[value1, value2, value3] AS array_field;

| extend array_field = pack_array(value1, value2, value3)

Usage

Syntax

pack_array(value1, value2, ..., valueN)

Parameters

Parameter	Description
value1	The first value to include in the array.
value2	The second value to include in the array.
...	Additional values to include in the array.
valueN	The last value to include in the array.

Returns

An array containing the specified values in the order they are provided.

Use case example

Use pack_array to consolidate span data into an array for a trace summary.

Query

['otel-demo-traces']
| extend span_summary = pack_array(['service.name'], kind, duration)

Run in Playground

Output

service.name	kind	duration	span_summary
frontend	server	123ms	[“frontend”, “server”, “123ms”]

This query creates a concise representation of span details.

List of related functions

• array_slice: Extracts a subset of elements from an array.
• array_concat: Combines multiple arrays.
• array_length: Returns the number of elements in an array.