> 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/logical/isnullorempty-stringvalue.md).

# IsNullorEmpty (StringValue)

| **Name**    | ***IsNullOrEmpty (String)***                                                               |
| ----------- | ------------------------------------------------------------------------------------------ |
| Syntax      | IsNullOrEmpty (String val)                                                                 |
| Purpose     | To determine whether a string is null or if its length is zero.                            |
| Description | Returns true if the specified parameter contains a null value or if string length is zero. |
| Return Type | Boolean                                                                                    |
| Parameters  | val \[System.String] – Expression that will be evaluated                                   |

![](https://github.com/astera-software/Astera_Data_Stack_v9/blob/main/.gitbook/assets/0%20\(15\).png)

**Example**

In this example, we will pass a null value to the function transformation object using a *Variables* object.

![](https://github.com/astera-software/Astera_Data_Stack_v9/blob/main/.gitbook/assets/1%20\(16\).png)

In the output, you can see that the Boolean value, True, has been returned as the passed value was empty or null.

![](https://github.com/astera-software/Astera_Data_Stack_v9/blob/main/.gitbook/assets/2%20\(16\).png)


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