> For the complete documentation index, see [llms.txt](https://documentation.astera.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://documentation.astera.com/astera-data-stack-v6/functions/string/mid-string-chars.md).

# Mid (String Chars)

| **Name**    | ***Mid***                                                                                                                                                                                                                                                                                                             |
| ----------- | --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
| Syntax      | Mid (String str, Integer startAt, Integer noOfChars)                                                                                                                                                                                                                                                                  |
| Purpose     | To get part of the string starting at startAt and of a specified length.                                                                                                                                                                                                                                              |
| Description | <p>Returns a string of characters from the string beginning at startAt and of maximum length equal to noOfChars. 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><p>noOfChars \[System.Int64] – Maximum number of characters to return</p>                                                                                                 |

![](https://github.com/astera-software/Astera_Data_Stack_v9/blob/main/.gitbook/assets/0%20\(74\).png)

**Example**

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

Where,

*str* = ABCDEFG

*startAt* = 3

noOfChars = 2

![](https://github.com/astera-software/Astera_Data_Stack_v9/blob/main/.gitbook/assets/1%20\(75\).png)

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, and of specified *noOfChars* length.

![](https://github.com/astera-software/Astera_Data_Stack_v9/blob/main/.gitbook/assets/2%20\(75\).png)


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