library/Rediska/Zend/Cache/Backend/Redis.php
public function remove($id)
    {
        $tags = explode(
            ',', $this->getRediska()->getFromHash(
                $this->_options['storage']['prefix_key'].$id, self::FIELD_TAGS
            )
        );

        $this->_getTransactionByKey($this->_options['storage']['prefix_key'].$id)
            ->delete($this->_options['storage']['prefix_key'].$id);
        $this->_getTransactionByKey($this->_options['storage']['set_ids'], $id)
            ->deleteFromSet( $this->_options['storage']['set_ids'], $id );
        foreach($tags as $tag) {
            $this->_getTransactionByKey($this->_options['storage']['prefix_tag_ids'] . $tag)
                ->deleteFromSet($this->_options['storage']['prefix_tag_ids'] . $tag, $id);
        }
        $result = $this->_execTransactions();
        if(count($result)){
            return array_shift($result);
        } else {
            return false;
        }
    }
public function remove($id)
    {
        $tags = explode(
            ',', $this->getRediska()->getFromHash(
                $this->_options['storage']['prefix_key'].$id, self::FIELD_TAGS
            )
        );

        $this->_getTransactionByKey($this->_options['storage']['prefix_key'].$id)
            ->delete($this->_options['storage']['prefix_key'].$id);
        $this->_getTransactionByKey($this->_options['storage']['set_ids'], $id)
            ->deleteFromSet( $this->_options['storage']['set_ids'], $id );
        foreach($tags as $tag) {
            $this->_getTransactionByKey($this->_options['storage']['prefix_tag_ids'] . $tag)
                ->deleteFromSet($this->_options['storage']['prefix_tag_ids'] . $tag, $id);
        }
        $result = $this->_execTransactions();
        if(count($result)){
            return array_shift($result);
        } else {
            return false;
        }
    }
Remove a cache record

@param  string $id Cache id
@return boolean True if no problem