public function read($key)
    {
        $query = $this->_table->find('kv');

        if ($key !== '*') {
            $query->where([
                $this->_table->aliasField('namespace') . ' IS' => $key
            ]);
        }

        return $query
            ->cache(function ($q) {
                return md5(serialize($q->clause('where')));
            }, $this->_cacheConfig)
            ->toArray();
    }