sub select

		'user_id' => array(
			'field_type' => 'Select',
			'list_flag' => TRUE,
			'edit_flag' => TRUE,
			'search_flag' => TRUE,
			'view_flag' => TRUE,
			'is_nullable' => FALSE,
			'field_options' => array(
				'source' => array(
					'source' => 'array',
					'data' => array(
						'Parent' => array(
							1 => 'Item 1',
							2 => 'Item 2',
						),
					),
				),
			),
		),