> ## 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If you encounter incorrect, outdated, or confusing documentation on this page, submit feedback: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/array-slice",
  "feedback": "Description of the issue"
}
```

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

</AgentInstructions>

# array_slice

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

The `array_slice` function in APL extracts a subset of elements from an array, based on specified start and end indices. This function is useful when you want to analyze or transform a portion of data within arrays, such as trimming logs, filtering specific events, or working with trace data in OpenTelemetry logs.

## 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, you can use `mvindex` to extract elements from an array. APL's `array_slice` is similar but more expressive, allowing you to specify slices with optional bounds.

    <CodeGroup>
      ```sql Splunk example theme={null}
      | eval sliced_array=mvindex(my_array, 1, 3)
      ```

      ```kusto APL equivalent theme={null}
      T | extend sliced_array = array_slice(my_array, 1, 3)
      ```
    </CodeGroup>
  </Accordion>

  <Accordion title="ANSI SQL users">
    In ANSI SQL, arrays are often handled using JSON functions or window functions, requiring workarounds to slice arrays. In APL, `array_slice` directly handles arrays, making operations more concise.

    <CodeGroup>
      ```sql SQL example theme={null}
      SELECT JSON_EXTRACT(my_array, '$[1:3]') AS sliced_array FROM my_table
      ```

      ```kusto APL equivalent theme={null}
      T | extend sliced_array = array_slice(my_array, 1, 3)
      ```
    </CodeGroup>
  </Accordion>
</AccordionGroup>

## Usage

### Syntax

```kusto theme={null}
array_slice(array, start, end)
```

### Parameters

| Parameter | Description                                                                                       |
| --------- | ------------------------------------------------------------------------------------------------- |
| `array`   | The input array to slice.                                                                         |
| `start`   | The starting index of the slice (inclusive). If negative, it’s counted from the end of the array. |
| `end`     | The ending index of the slice (exclusive). If negative, it’s counted from the end of the array.   |

### Returns

An array containing the elements from the specified slice. If the indices are out of bounds, it adjusts to return valid elements without error.

## Use case example

Filter spans from trace data to analyze a specific range of events.

**Query**

```kusto theme={null}
['otel-demo-traces']
| where array_length(events) > 4
| extend sliced_events = array_slice(events, -3, -1)
```

[Run in Playground](https://play.axiom.co/axiom-play-qf1k/query?initForm=%7B%22apl%22%3A%22%5B'otel-demo-traces'%5D%20%7C%20where%20array_length\(events\)%20%3E%204%20%7C%20extend%20sliced_events%20%3D%20array_slice\(events%2C%20-3%2C%20-1\)%22%7D)

**Output**

```json events theme={null}
[
  {
    "timestamp": 1734001336443987200,
    "attributes": null,
    "name": "prepared"
  },
  {
    "attributes": {
      "feature_flag.provider_name": "flagd",
      "feature_flag.variant": "off",
      "feature_flag.key": "paymentServiceUnreachable"
    },
    "name": "feature_flag",
    "timestamp": 1734001336444001800
  },
  {
    "name": "charged",
    "timestamp": 1734001336445970200,
    "attributes": {
      "custom": {
        "app.payment.transaction.id": "49567406-21f4-41aa-bab2-69911c055753"
      }
    }
  },
  {
    "name": "shipped",
    "timestamp": 1734001336446488600,
    "attributes": {
      "custom": {
        "app.shipping.tracking.id": "9a3b7a5c-aa41-4033-917f-50cb7360a2a4"
      }
    }
  },
  {
    "attributes": {
      "feature_flag.variant": "off",
      "feature_flag.key": "kafkaQueueProblems",
      "feature_flag.provider_name": "flagd"
    },
    "name": "feature_flag",
    "timestamp": 1734001336461096700
  }
]
```

```json sliced_events theme={null}
[
  {
    "name": "charged",
    "timestamp": 1734001336445970200,
    "attributes": {
      "custom": {
        "app.payment.transaction.id": "49567406-21f4-41aa-bab2-69911c055753"
      }
    }
  },
  {
    "name": "shipped",
    "timestamp": 1734001336446488600,
    "attributes": {
      "custom": {
        "app.shipping.tracking.id": "9a3b7a5c-aa41-4033-917f-50cb7360a2a4"
      }
    }
  }
]
```

Slices the last three events from the `events` array, excluding the final one.

## List of related functions

* [array\_concat](/apl/scalar-functions/array-functions/array-concat): Combines multiple arrays.
* [array\_reverse](/apl/scalar-functions/array-functions/array-reverse): Reverses the order of array elements.
* [array\_shift\_right](/apl/scalar-functions/array-functions/array-shift-right): Shifts array elements to the right.