library/Rediska/Key/Hash.php
public function remove($field)
    {
        $result = $this->_getRediskaOn()->deleteFromHash($this->getName(), $field);

        if (!is_null($this->getExpire()) && $result) {
            $this->expire($this->getExpire(), $this->isExpireTimestamp());
        }

        return $result;
    }
public function remove($field)
    {
        $result = $this->_getRediskaOn()->deleteFromHash($this->getName(), $field);

        if (!is_null($this->getExpire()) && $result) {
            $this->expire($this->getExpire(), $this->isExpireTimestamp());
        }

        return $result;
    }
Remove field from hash

@param mixed  $field Field
@return boolean