public function delete(array $data = array())
    {
        $sql = 'DELETE FROM log';

        $conditions = array();

        if (empty($data['log_id'])) {
            $sql .= " WHERE log_id IS NOT NULL";
        } else {
            settype($data['log_id'], 'array');
            $placeholders = rtrim(str_repeat('?,', count($data['log_id'])), ',');
            $sql .= " WHERE log_id IN($placeholders)";
            $conditions = array_merge($conditions, $data['log_id']);
        }

        if (!empty($data['type'])) {
            settype($data['type'], 'array');
            $placeholders = rtrim(str_repeat('?,', count($data['type'])), ',');
            $sql .= " AND type IN($placeholders)";
            $conditions = array_merge($conditions, $data['type']);
        }

        $this->db->run($sql, $conditions);
        return true;
    }