public function importIssueFiles($issue, $oldId, $slug)
    {
        $issueFilesSql = "SELECT * FROM issue_files WHERE issue_id = :id";
        $issueFilesStatement = $this->dbalConnection->prepare($issueFilesSql);
        $issueFilesStatement->bindValue('id', $oldId);
        $issueFilesStatement->execute();

        $issueFiles = $issueFilesStatement->fetchAll();
        foreach ($issueFiles as $issueFile) {
            $this->importIssueFile($issueFile['file_id'], $oldId, $issue, $slug);
        }
    }