# StartMetadataModelCreation
<a name="API_StartMetadataModelCreation"></a>

Creates source metadata model of the given type with the specified properties for schema conversion operations.

**Note**  
This action supports only these directions: from SQL Server to Aurora PostgreSQL, or from SQL Server to RDS for PostgreSQL.

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

```
{
   "MetadataModelName": "string",
   "MigrationProjectIdentifier": "string",
   "Properties": { ... },
   "SelectionRules": "string"
}
```

## Request Parameters
<a name="API_StartMetadataModelCreation_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.

 ** [MetadataModelName](#API_StartMetadataModelCreation_RequestSyntax) **   <a name="DMS-StartMetadataModelCreation-request-MetadataModelName"></a>
The name of the metadata model.  
Type: String  
Required: Yes

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

 ** [Properties](#API_StartMetadataModelCreation_RequestSyntax) **   <a name="DMS-StartMetadataModelCreation-request-Properties"></a>
The properties of metadata model in JSON format. This object is a Union. Only one member of this object can be specified or returned.  
Type: [MetadataModelProperties](API_MetadataModelProperties.md) object  
 **Note: **This object is a Union. Only one member of this object can be specified or returned.  
Required: Yes

 ** [SelectionRules](#API_StartMetadataModelCreation_RequestSyntax) **   <a name="DMS-StartMetadataModelCreation-request-SelectionRules"></a>
The JSON string that specifies the location where the metadata model will be created. Selection rules must specify a single schema. For more information, see Selection Rules in the DMS User Guide.  
Type: String  
Required: Yes

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

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

## Response Elements
<a name="API_StartMetadataModelCreation_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_StartMetadataModelCreation_ResponseSyntax) **   <a name="DMS-StartMetadataModelCreation-response-RequestIdentifier"></a>
The identifier for the metadata model creation operation.  
Type: String

## Errors
<a name="API_StartMetadataModelCreation_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

 ** 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

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

### Sample Request
<a name="API_StartMetadataModelCreation_Example_1"></a>

This example illustrates creation of a metadata model for a SQL statement. The provided selection rule serves as context to resolve and place the metadata model within the database schema hierarchy. The metadata model name acts as a unique identifier that can be referenced in subsequent operations.

```
POST / HTTP/1.1
Host: dms.<region>.<domain>
Content-Type: application/x-amz-json-1.1
Content-Length: <PayloadSizeBytes>
Authorization: AWS4-HMAC-SHA256 Credential=<Credential>, SignedHeaders=<SignedHeaders>, Signature=<Signature>
X-Amz-Date: <Date>
X-Amz-Target: AmazonDMSv20160101.StartMetadataModelCreation
{
    "MigrationProjectIdentifier": "arn:aws:dms:us-east-1:012345678901:migration-project:EXAMPLEABCDEFGHIJKLMNOPQRS",
    "SelectionRules": "{\"rules\": [{\"rule-type\": \"selection\", \"rule-id\": \"1\", \"rule-name\": \"1\", \"object-locator\": {\"server-name\": \"source-database-server.us-east-1.rds.amazonaws.com\", \"database-name\": \"database1\", \"schema-name\": \"schema1\"}, \"rule-action\": \"explicit\"} ]}",
    "MetadataModelName": "Statement1",
    "Properties": {
        "StatementProperties": {
            "Definition": "SELECT * FROM table1;"
        }
    }
}
```

### Sample Response
<a name="API_StartMetadataModelCreation_Example_2"></a>

This example illustrates one usage of StartMetadataModelCreation.

```
HTTP/1.1 200 OK
x-amzn-RequestId: <RequestId>
Content-Type: application/x-amz-json-1.1
Content-Length: <PayloadSizeBytes>
Date: <Date>
{
    "RequestIdentifier": "00000000-0000-0000-0000-000000000000"
}
```

## See Also
<a name="API_StartMetadataModelCreation_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/StartMetadataModelCreation) 
+  [AWS SDK for .NET V4](https://docs.aws.amazon.com/goto/DotNetSDKV4/dms-2016-01-01/StartMetadataModelCreation) 
+  [AWS SDK for C\$1\$1](https://docs.aws.amazon.com/goto/SdkForCpp/dms-2016-01-01/StartMetadataModelCreation) 
+  [AWS SDK for Go v2](https://docs.aws.amazon.com/goto/SdkForGoV2/dms-2016-01-01/StartMetadataModelCreation) 
+  [AWS SDK for Java V2](https://docs.aws.amazon.com/goto/SdkForJavaV2/dms-2016-01-01/StartMetadataModelCreation) 
+  [AWS SDK for JavaScript V3](https://docs.aws.amazon.com/goto/SdkForJavaScriptV3/dms-2016-01-01/StartMetadataModelCreation) 
+  [AWS SDK for Kotlin](https://docs.aws.amazon.com/goto/SdkForKotlin/dms-2016-01-01/StartMetadataModelCreation) 
+  [AWS SDK for PHP V3](https://docs.aws.amazon.com/goto/SdkForPHPV3/dms-2016-01-01/StartMetadataModelCreation) 
+  [AWS SDK for Python](https://docs.aws.amazon.com/goto/boto3/dms-2016-01-01/StartMetadataModelCreation) 
+  [AWS SDK for Ruby V3](https://docs.aws.amazon.com/goto/SdkForRubyV3/dms-2016-01-01/StartMetadataModelCreation)