# Mid (String)

| **Name**    | ***Mid***                                                                                                                                                                                                                                                                    |
| ----------- | ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
| Syntax      | Mid (String str, Integer startAt)                                                                                                                                                                                                                                            |
| Purpose     | To get all characters starting with startAt position.                                                                                                                                                                                                                        |
| Description | <p>Returns a string of characters from the string beginning at startAt. If startAt is greater than or equal to string length, empty string is returned.</p><p><strong>Note:</strong> This function is identical to Substring and is retained for backward compatibility.</p> |
| Return Type | String                                                                                                                                                                                                                                                                       |
| Parameters  | <p>str \[System.String] – Value for which length will be returned</p><p>startAt \[System.Int64] – Start position of the string to return</p>                                                                                                                                 |

![](https://3083465318-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FsR50Wa7EwZGlmPSAMkkf%2Fuploads%2FhFHJ9PexquDrEvADA7Jv%2F0.png?alt=media)

**Example**

In this example, we are passing the required parameters to the function transformation object using a *Variables* object.

Where,

*str* = ABCDEFG

*startAt* = 3

![](https://3083465318-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FsR50Wa7EwZGlmPSAMkkf%2Fuploads%2FFRXtaelvX8ApAKLqTtnI%2F1.png?alt=media)

Right-click on the function transformation object and select *Preview Output.* You can see that Astera Data Stack has returned a string beginning from the specified *startAt* position.

![](https://3083465318-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FsR50Wa7EwZGlmPSAMkkf%2Fuploads%2FbJN3pCtaQxDPVJiAxseU%2F2.png?alt=media)


---

# Agent Instructions: Querying This Documentation

If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question.

Perform an HTTP GET request on the current page URL with the `ask` query parameter:

```
GET https://documentation.astera.com/astera-data-stack-v10/functions/string/mid-string.md?ask=<question>
```

The question should be specific, self-contained, and written in natural language.
The response will contain a direct answer to the question and relevant excerpts and sources from the documentation.

Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.