Redis hmset, hmget

<?php

use Illuminate\Support\Facades\Redis;

// ...
    public static function getByIdWithCache($id) {
        Redis::select(6);
        $key = sprintf("CarV2:MERCHANT:%d", $id);
        $columns = array( "id", "merchant_type_id","member_username","company_full_name",
            "city_code","recommend_id","name");
        $values = Redis::hMget($key, $columns);
        if (!empty($values[0])) {
            $mch = new Merchants();
            for ($i = 0, $n = count($values); $i < $n; $i++) {
                $mch->setAttribute($columns[$i], $values[$i]);
            }
            return $mch;
        }
        /** @var $mch Merchants */
        $mch = self::where("id", "=", $id)->get($columns)->first();
        if (empty($mch)) {
            Redis::hSet($key, "id", 0);
            return $mch;
        }
        foreach ($columns as $c) {
            Redis::hSet($key, $c, $mch->getAttribute($c));
        }
        Redis::expire($key, 3600);
        return $mch;
    }

?>