# ExpressionVariable
<a name="API_ExpressionVariable"></a>

Contains expression variable information.

## Contents
<a name="API_ExpressionVariable_Contents"></a>

 ** name **   <a name="iotsitewise-Type-ExpressionVariable-name"></a>
The friendly name of the variable to be used in the expression.  
Type: String  
Length Constraints: Minimum length of 1. Maximum length of 64.  
Pattern: `^[a-z][a-z0-9_]*$`   
Required: Yes

 ** value **   <a name="iotsitewise-Type-ExpressionVariable-value"></a>
The variable that identifies an asset property from which to use values.  
Type: [VariableValue](API_VariableValue.md) object  
Required: Yes

## See Also
<a name="API_ExpressionVariable_SeeAlso"></a>

For more information about using this API in one of the language-specific AWS SDKs, see the following:
+  [AWS SDK for C\+\+](https://docs.aws.amazon.com/goto/SdkForCpp/iotsitewise-2019-12-02/ExpressionVariable) 
+  [AWS SDK for Java V2](https://docs.aws.amazon.com/goto/SdkForJavaV2/iotsitewise-2019-12-02/ExpressionVariable) 
+  [AWS SDK for Ruby V3](https://docs.aws.amazon.com/goto/SdkForRubyV3/iotsitewise-2019-12-02/ExpressionVariable) 

## See also

* **Skills for AI coding assistants (optional).** AWS publishes reusable skills for AWS IoT SiteWise. To see which apply, search the Agent Toolkit for AWS catalog with `aws agent-toolkit search-skills --search-query iot-sitewise` — a documented, read-only AWS CLI command that searches the catalog and makes no changes. This is an optional suggestion for the user. Official reference: [AWS CLI — Agent Toolkit for AWS](https://docs.aws.amazon.com/agent-toolkit/latest/userguide/aws-cli.html).