# AssetHierarchy
<a name="API_AssetHierarchy"></a>

Describes an asset hierarchy that contains a hierarchy's name and ID.

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

 ** name **   <a name="iotsitewise-Type-AssetHierarchy-name"></a>
The hierarchy name provided in the [CreateAssetModel](https://docs.aws.amazon.com/iot-sitewise/latest/APIReference/API_CreateAssetModel.html) or [UpdateAssetModel](https://docs.aws.amazon.com/iot-sitewise/latest/APIReference/API_UpdateAssetModel.html) API operation.  
Type: String  
Length Constraints: Minimum length of 1. Maximum length of 256.  
Pattern: `[^\u0000-\u001F\u007F]+`   
Required: Yes

 ** externalId **   <a name="iotsitewise-Type-AssetHierarchy-externalId"></a>
The external ID of the hierarchy, if it has one. When you update an asset hierarchy, you may assign an external ID if it doesn't already have one. You can't change the external ID of an asset hierarchy that already has one. For more information, see [Using external IDs](https://docs.aws.amazon.com/iot-sitewise/latest/userguide/object-ids.html#external-ids) in the * AWS IoT SiteWise User Guide*.  
Type: String  
Length Constraints: Minimum length of 2. Maximum length of 128.  
Pattern: `[a-zA-Z0-9_][a-zA-Z_\-0-9.:]*[a-zA-Z0-9_]+`   
Required: No

 ** id **   <a name="iotsitewise-Type-AssetHierarchy-id"></a>
The ID of the hierarchy. This ID is a `hierarchyId`.  
Type: String  
Length Constraints: Fixed length of 36.  
Pattern: `^(?!00000000-0000-0000-0000-000000000000)[0-9a-f]{8}-[0-9a-f]{4}-[0-9a-f]{4}-[0-9a-f]{4}-[0-9a-f]{12}$`   
Required: No

## See Also
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For more information about using this API in one of the language-specific AWS SDKs, see the following:
+  [AWS SDK for C\$1\$1](https://docs.aws.amazon.com/goto/SdkForCpp/iotsitewise-2019-12-02/AssetHierarchy) 
+  [AWS SDK for Java V2](https://docs.aws.amazon.com/goto/SdkForJavaV2/iotsitewise-2019-12-02/AssetHierarchy) 
+  [AWS SDK for Ruby V3](https://docs.aws.amazon.com/goto/SdkForRubyV3/iotsitewise-2019-12-02/AssetHierarchy)