> ## Documentation Index
> Fetch the complete documentation index at: https://axiom.co/docs/llms.txt
> Use this file to discover all available pages before exploring further.

<AgentInstructions>

## Submitting Feedback

If you encounter incorrect, outdated, or confusing documentation on this page, submit feedback:

POST https://axiom.co/docs/feedback

```json
{
  "path": "/apl/scalar-functions/array-functions/isarray",
  "feedback": "Description of the issue"
}
```

Only submit feedback when you have something specific and actionable to report.

</AgentInstructions>

# isarray

> This page explains how to use the isarray function in APL.

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’s particularly useful when working with data that contains fields with mixed data types or optional nested arrays.

## 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.

<AccordionGroup>
  <Accordion title="Splunk SPL users">
    In Splunk SPL, similar functionality is achieved by analyzing the data structure manually, as SPL doesn’t have a direct equivalent to `isarray`. APL simplifies this task by providing the `isarray` function to directly evaluate whether a value is an array.

    <CodeGroup>
      ```sql Splunk example theme={null}
      | eval is_array=if(isnotnull(mvcount(field)), "true", "false")
      ```

      ```kusto APL equivalent theme={null}
      ['dataset.name']
      | extend is_array=isarray(field)
      ```
    </CodeGroup>
  </Accordion>

  <Accordion title="ANSI SQL users">
    In ANSI SQL, there is no built-in function for directly checking if a value is an array. You might need to rely on JSON functions or structural parsing. APL provides the `isarray` function as a more straightforward solution.

    <CodeGroup>
      ```sql SQL example theme={null}
      SELECT CASE
               WHEN JSON_TYPE(field) = 'ARRAY' THEN TRUE
               ELSE FALSE
             END AS is_array
      FROM dataset_name;
      ```

      ```kusto APL equivalent theme={null}
      ['dataset.name']
      | extend is_array=isarray(field)
      ```
    </CodeGroup>
  </Accordion>
</AccordionGroup>

## Usage

### Syntax

```kusto theme={null}
isarray(value)
```

### Parameters

| Parameter | Description                          |
| --------- | ------------------------------------ |
| `value`   | The value to check if it’s an array. |

### Returns

A boolean value:

* `true` if the specified value is an array.
* `false` otherwise.

## Use case example

Filter for records where the `events` field contains an array.

**Query**

```kusto theme={null}
['otel-demo-traces']
| take 50
| summarize events_array = make_list(events)
| extend is_array = isarray(events_array)
```

[Run in Playground](https://play.axiom.co/axiom-play-qf1k/query?initForm=%7B%22apl%22%3A%22%5B'otel-demo-traces'%5D%20%7C%20take%2050%20%7C%20summarize%20events_array%20%3D%20make_list\(events\)%20%7C%20extend%20is_array%20%3D%20isarray\(events_array\)%22%7D)

**Output**

| is\_array |
| --------- |
| true      |

## List of related functions

* [array\_length](/apl/scalar-functions/array-functions/array-length): Returns the number of elements in an array.
* [array\_index\_of](/apl/scalar-functions/array-functions/array-index-of): Finds the index of an element in an array.
* [array\_slice](/apl/scalar-functions/array-functions/array-slice): Extracts a subset of elements from an array.