# StartMetadataModelAssessment
<a name="API_StartMetadataModelAssessment"></a>

Creates a database migration assessment report by assessing the migration complexity for your source database. A database migration assessment report summarizes all of the schema conversion tasks. It also details the action items for database objects that can't be converted to the database engine of your target database instance. 

## Request Syntax
<a name="API_StartMetadataModelAssessment_RequestSyntax"></a>

```
{
   "MigrationProjectIdentifier": "string",
   "SelectionRules": "string"
}
```

## Request Parameters
<a name="API_StartMetadataModelAssessment_RequestParameters"></a>

For information about the parameters that are common to all actions, see [Common Parameters](CommonParameters.md).

The request accepts the following data in JSON format.

 ** [MigrationProjectIdentifier](#API_StartMetadataModelAssessment_RequestSyntax) **   <a name="DMS-StartMetadataModelAssessment-request-MigrationProjectIdentifier"></a>
The migration project name or Amazon Resource Name (ARN).  
Type: String  
Length Constraints: Maximum length of 255.  
Required: Yes

 ** [SelectionRules](#API_StartMetadataModelAssessment_RequestSyntax) **   <a name="DMS-StartMetadataModelAssessment-request-SelectionRules"></a>
A value that specifies the database objects to assess.  
Type: String  
Required: Yes

## Response Syntax
<a name="API_StartMetadataModelAssessment_ResponseSyntax"></a>

```
{
   "RequestIdentifier": "string"
}
```

## Response Elements
<a name="API_StartMetadataModelAssessment_ResponseElements"></a>

If the action is successful, the service sends back an HTTP 200 response.

The following data is returned in JSON format by the service.

 ** [RequestIdentifier](#API_StartMetadataModelAssessment_ResponseSyntax) **   <a name="DMS-StartMetadataModelAssessment-response-RequestIdentifier"></a>
The identifier for the assessment operation.  
Type: String

## Errors
<a name="API_StartMetadataModelAssessment_Errors"></a>

For information about the errors that are common to all actions, see [Common Error Types](CommonErrors.md).

 ** AccessDeniedFault **   
 AWS DMS was denied access to the endpoint. Check that the role is correctly configured.    
 ** message **   

HTTP Status Code: 400

 ** InvalidResourceStateFault **   
The resource is in a state that prevents it from being used for database migration.    
 ** message **   

HTTP Status Code: 400

 ** KMSKeyNotAccessibleFault **   
 AWS DMS cannot access the KMS key.    
 ** message **   

HTTP Status Code: 400

 ** ResourceAlreadyExistsFault **   
The resource you are attempting to create already exists.    
 ** message **   
  
 ** resourceArn **   

HTTP Status Code: 400

 ** ResourceNotFoundFault **   
The resource could not be found.    
 ** message **   

HTTP Status Code: 400

 ** ResourceQuotaExceededFault **   
The quota for this resource quota has been exceeded.    
 ** message **   

HTTP Status Code: 400

 ** S3AccessDeniedFault **   
Insufficient privileges are preventing access to an Amazon S3 object.  
HTTP Status Code: 400

 ** S3ResourceNotFoundFault **   
A specified Amazon S3 bucket, bucket folder, or other object can't be found.  
HTTP Status Code: 400

## Examples
<a name="API_StartMetadataModelAssessment_Examples"></a>

### Example
<a name="API_StartMetadataModelAssessment_Example_1"></a>

This example illustrates one usage of StartMetadataModelAssessment.

#### Sample Request
<a name="API_StartMetadataModelAssessment_Example_1_Request"></a>

```
awsdms start-metadata-model-assessment --migration-project-identifier
arn:aws:dms:us-east-1:012345678901:migration-project:EXAMPLEABCDEFGHIJKLMNOPQRSTUVWXYZ012345 
--selection-rules "{\"rules\": [{\"rule-type\": \"selection\",\"rule-id\": \"1\",\"rule-name\": \"1\",\"object-locator\": {\"server-name\": \"aurora-pg.cluster-A1B2C3D4E5F6.us-east-1.rds.amazonaws.com\", \"schema-name\": \"schema1\", \"table-name\": \"Cities\"},\"rule-action\": \"explicit\"} ]}"
```

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

For more information about using this API in one of the language-specific AWS SDKs, see the following:
+  [AWS Command Line Interface V2](https://docs.aws.amazon.com/goto/cli2/dms-2016-01-01/StartMetadataModelAssessment) 
+  [AWS SDK for .NET V4](https://docs.aws.amazon.com/goto/DotNetSDKV4/dms-2016-01-01/StartMetadataModelAssessment) 
+  [AWS SDK for C\$1\$1](https://docs.aws.amazon.com/goto/SdkForCpp/dms-2016-01-01/StartMetadataModelAssessment) 
+  [AWS SDK for Go v2](https://docs.aws.amazon.com/goto/SdkForGoV2/dms-2016-01-01/StartMetadataModelAssessment) 
+  [AWS SDK for Java V2](https://docs.aws.amazon.com/goto/SdkForJavaV2/dms-2016-01-01/StartMetadataModelAssessment) 
+  [AWS SDK for JavaScript V3](https://docs.aws.amazon.com/goto/SdkForJavaScriptV3/dms-2016-01-01/StartMetadataModelAssessment) 
+  [AWS SDK for Kotlin](https://docs.aws.amazon.com/goto/SdkForKotlin/dms-2016-01-01/StartMetadataModelAssessment) 
+  [AWS SDK for PHP V3](https://docs.aws.amazon.com/goto/SdkForPHPV3/dms-2016-01-01/StartMetadataModelAssessment) 
+  [AWS SDK for Python](https://docs.aws.amazon.com/goto/boto3/dms-2016-01-01/StartMetadataModelAssessment) 
+  [AWS SDK for Ruby V3](https://docs.aws.amazon.com/goto/SdkForRubyV3/dms-2016-01-01/StartMetadataModelAssessment)