protected function maybeCheckTermExistsInDatabase($term_id)
    {
        if (!isset($this->config['checkExistence']) or false == $this->config['checkExistence']) {
            return;
        }
        $tableName = $this->grabPrefixedTableNameFor('terms');
        if (!$this->grabFromDatabase($tableName, 'term_id', ['term_id' => $term_id])) {
            throw new \RuntimeException("A term with an id of $term_id does not exist", 1);
        }
    }