isarray

The isarray function in APL checks whether a specified value is an array. Use this function to validate input data, handle dynamic schemas, or filter for records where a field is explicitly an array. It is particularly useful when working with data that contains fields with mixed data types or optional nested arrays.

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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.

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Usage

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Syntax

isarray(value)

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Parameters

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Returns

A boolean value:

• true if the specified value is an array.
• false otherwise.

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Use case example

Filter for records where the events field contains an array.

Query

['otel-demo-traces']
| take 50
| summarize events_array = make_list(events)
| extend is_array = isarray(events_array)

Run in Playground

Output

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List of related functions

• array_length: Returns the number of elements in an array.
• array_index_of: Finds the index of an element in an array.
• array_slice: Extracts a subset of elements from an array.