Using GraphQL Fragments in PHP
You can execute GraphQL queries in PHP. In this case, we even show using a GraphQL Fragment.
add_action( 'init', function() {
	$results = graphql([
		'query' => '
		{
		  posts {
		    nodes {
		      ...PostFields
		    }
		  }
		}
		fragment PostFields on Post {
		  id
		  title
		}
		',
	]);
	var_dump( $results );
	die();
} );Executing this code leads to the following output:

Additionally, if you were to define your fragment in another file, such as the file that is rendering the data, you can define fragments as variables and concatenate them like so:
$fragment = '
  fragment PostFields on Post {
    id
    title
}
';
$results = graphql([
  'query' => '
    {
      posts {
        nodes {
	  ...PostFields
	}
      }
    }
  ' . $fragment ,
]);