（三）基于商品属性的相似商品推荐算法——批量处理商品属性，得到属性前缀及完整属性字符串

$sql = "SELECT goods_code FROM sj_goods WHERE goods_code>{$lastCode} ORDER BY goods_code ASC" . ($limit>0? " LIMIT $limit":"");

$list = $this->db[‘seller‘]->getAll($sql);
$goodsCodes = [];
$count = 0;
while ($row = $list->fetch(PDO::FETCH_ASSOC)) {
    $count++;
    $goodsCodes[] = $row[‘goods_code‘];
    if ($count%100 == 0) {
        // 每100个商品查询一次属性
        $properties = $this->genGoodsProperties($goodsCodes);
        // 属性入库
        $this->insertGoodsProperties($properties) or die($goodsCodes[0].‘ 异常！！‘);
        $goodsCodes = [];
    }
}

// 别忘了不够100个商品的情况
if (!empty($goodsCodes)) {
    $properties = $this->genGoodsProperties($goodsCodes);
    $this->insertGoodsProperties($properties) or die($goodsCodes[0].‘ 异常！！‘);
}

$sql = "SELECT t1.goods_code,t1.brand_code,t4.property_name,t3.property_code,t3.property_value FROM sj_goods_product t1 LEFT JOIN sj_product t2 ON t2.product_code = t1.product_code LEFT JOIN sj_style_properties t3 ON t3.style_code = t2.style_code LEFT JOIN sp_product_property t4 ON t4.property_code = t3.property_code WHERE t1.goods_code in (‘". implode("‘,‘", $goodsCodes) ."‘)";

// 属性前缀为：适用人群-佩戴场合-机芯类型-价格区间-表盘形状-表盘直径，后面的属性排列顺序可以随意
$needs = [31=>‘适用人群‘, 40=>‘佩戴场合‘, 1=>‘机芯类型‘, 39=>‘价格区间‘, 9=>‘表盘形状‘, 11=>‘表盘直径‘, 13=>‘表盘刻度‘, 17=>‘表带材质‘, 14=>‘表盘颜色‘, 25=>‘防水‘, 3=>‘外壳材质‘, 38=>‘表盘宽度‘, 3=>‘表盘厚度‘, 12=>‘镜面材质‘, 16=>‘表壳底盖‘, 19=>‘表带颜色‘];

private function genGoodsProperties($goodsCodes)
{
    // 属性前缀为：适用人群-佩戴场合-机芯类型-价格区间-表盘形状-表盘直径，后面的属性排列顺序可以随意
    $needs = [31=>‘适用人群‘, 40=>‘佩戴场合‘, 1=>‘机芯类型‘, 39=>‘价格区间‘, 9=>‘表盘形状‘, 11=>‘表盘直径‘, 13=>‘表盘刻度‘, 17=>‘表带材质‘, 14=>‘表盘颜色‘, 25=>‘防水‘, 3=>‘外壳材质‘, 38=>‘表盘宽度‘, 3=>‘表盘厚度‘, 12=>‘镜面材质‘, 16=>‘表壳底盖‘, 19=>‘表带颜色‘];
    $properties = $this->getGoodsProperty($goodsCodes);
    $return = [];
    foreach ($goodsCodes as $goodsCode) {
        $prefix = ‘‘;
        $full = ‘‘;
        foreach ($needs as $key => $value) {
            $brandCode = 0;
            // 这里的 $properties 是第1)步得到的，已转换成了map
            if (isset($properties[$goodsCode][$key]) && !empty($properties[$goodsCode][$key])) {
                // 如果商品有此属性就拼接属性值
                $full .= $properties[$goodsCode][$key][‘property_value‘].‘|‘;
                $brandCode = $properties[$goodsCode][$key][‘brand_code‘];
            } else {
                // 如果商品没有这个属性，或属性值为空，那拼接一个 0
                $full .= ‘0|‘;
            }

            // 临界点（拿到属性前缀）
            if ($value == ‘表盘直径‘) {
                $prefix = $full;
                // 加入品牌信息
                $full .= $brandCode.‘|‘;
            }
        }

        // 截取掉最后多余的 |
        $prefix = substr($prefix, 0, -1);
        $full = substr($full, 0, -1);
        // 拆分多选属性
        $prefix = $this->splitProperties($prefix);
        $full = $this->splitProperties($full);
        $return[$goodsCode] = [$prefix, $full];
    }
    return $return;
}

$prefix = ‘96|297,300|195,41|64|46|218‘;
$full   = ‘96|297,300|195,41|64|46|218|87|220,222|51,242|58|185|198,200|41mm|12mm|276|257‘;

$prefix = ‘96|298,297,299|195|64|46|218‘;
$full   = ‘96|298,297,299|195|64|46|218|87|220,222|242|58|185|200|41mm|L619/888|276|257‘;

private function splitProperties($propertyPrefixs)
{
    // 没有多选属性，直接返回
    if (strpos($propertyPrefixs, ‘,‘) === false) {
        return [$propertyPrefixs];
    }

    // 原属性组（也是结果）
    $origin = [$propertyPrefixs];
    $return = ‘‘;
    // 拆分属性位
    $arr1 = explode(‘|‘, $propertyPrefixs);
    // 循环属性位
    foreach ($arr1 as $k => $v) {
        // 多选属性位
        if (strpos($v, ‘,‘) !== false) {
            $new = [];
            // 拆分多选属性
            $arr2 = explode(‘,‘, $v);
            foreach ($arr2 as $kk => $vv) {
                // 循环原属性组，替换原属性位
                foreach ($origin as $kkk => $vvv) {
                    $prefixs = str_replace($v, $vv, $vvv);
                    // 替换结果
                    $new[] = $prefixs;
                }
            }
            // 更新的原属性组
            $origin = $new;
        }
    }
    return $origin;
}