# Add Identifier

Add an identifier of the specified type to the record.

## Example

This example shows how to use the Add Identifier transformation to add a UUID v4 identifier to your record.

```json
{
  "operation": "add_identifier",
  "arguments": {
    "key": "id_field",
    "type": "uuid_v4"
  }
}
```

Given the input record:

```json
{
  "existing_field": "some_value"
}
```

The output record will be:

```json
{
  "existing_field": "some_value",
  "id_field": "65722aa2-e942-4334-af01-8e7e8bcbfa51"
}
```

### Supported Types

The Add Identifier transformation supports the following types:

- uuid_v4: A randomly generated UUID(default)
- uuid_v7: A randomly generated UUID using unix time