# Identifying resources with AWS Cloud Control API
<a name="resource-identifier"></a>

Every resource type has a property that is defined as its *primary identifier*. The value of this property must be unique for each resource of that type in a given AWS account and AWS Region. For example, many resource types include a `Name` property that must be unique for each resource of that type. In some cases, the primary identifier is defined as a combination of multiple properties that together form a unique identifier. By using this primary identifier, combined with the resource type, you can specify exactly which resource on which you want to perform resource operations such as `update-resource` or `delete-resource`.

In addition, some resource types define *secondary identifiers* that can also be used to uniquely identify resources of that type.

To determine which resource property (or combination of properties) is the primary identifier for a resource type, refer to the `primaryIdentifier` attribute of the resource type schema. The schema includes secondary identifiers defined, as well. For more information, see [Viewing resource type schemas](resource-types.md#resource-types-schemas).

## Getting a resource's primary identifier
<a name="resource-identifier-getting"></a>

You can find the identifier *value* for a specific resource by using Cloud Control API commands. Each of the following commands returns a `ProgressEvent` object that contains the primary identifier of the specified resources:
+ 

  ```
  cancel-resource-request
  ```
+ 

  ```
  create-resource
  ```
+ 

  ```
  get-resource-request-status
  ```
+ 

  ```
  list-resource-requests
  ```

## Using a resource's primary identifier
<a name="resource-identifier-using"></a>

When using Cloud Control API commands, you can specify the primary identifier or any secondary identifier defined for the resource type in its resource schema. You can only specify one identifier. Primary identifiers can be specified as a string or JSON; secondary identifiers must be specified as JSON.

For compound primary identifiers (that is, one that consists of multiple resource properties strung together), to specify the primary identifier as a string, list the property values *in the order that they are specified* in the primary identifier definition, separated by `|`.

For example, the primary identifier for the resource is defined as:

`"primaryIdentifier": [ "/properties/DatabaseName", "/properties/TableName" ]`

So, to specify the primary identifier of a resource as a string, you use the following format.

`DatabaseName|TableName`

For example, given a database with a database name of `MyDatabase` and table name of `MyTable`, you specify `MyDatabase|MyTable`.

For compound identifiers specified as JSON, property order is not required, as shown in the following example.

```
{
  "TableName": "MyTable",
  "DatabaseName": "MyDatabase"
}
```

For more information about resource identifiers, see [primaryidentifier](https://docs.aws.amazon.com/cloudformation-cli/latest/userguide/resource-type-schema.html#schema-properties-primaryidentifier) in the *CloudFormation Command Line Interface User Move for Extension Development*.