Question

    Product => id, name, price  
    Discount => id, percent, date_start, date_end  
    discount_products (Table) => product_id, discount_id 
    
    Product::addSelect(['discount_price' => function ($query) {
        $query->selectRaw('SUM(products.price * (100 - discounts.percent) / 100)')
            ->from('discounts')
            ->join('discount_products', 'discounts.id', '=', 'discount_products.discount_id')
            ->whereColumn('discount_products.product_id', 'products.id')
            ->where('date_start', '<=', Carbon::today()->toDateString())
            ->where('date_end', '>=', Carbon::today()->toDateString())
            ->groupBy('id')
            ->orderBy('id', 'desc')
            ->limit(1);
        }])
    //  ->orderByRaw('COALESCE(discount_price, price) ASC')     // not working
    //  ->orderByRaw('discount_price ASC')                      // working
    //  ->orderByRaw('price ASC')                               // working
        ->get();

你好朋友，首先对不起我的英语。我正在使用PostgreSQL作为数据库。

我想按价格订购产品。
如果产品具有“折扣价格”，请使用它或使用“价格”字段。请帮忙。

Answer 1

Product::fromSub(function ($query) {
    $query->from("products")
        ->addSelect(['discount_price' => function ($query) {
            $query->selectRaw('SUM(products.price * (100 - discounts.percent) / 100)')
                ->from('discounts')
                ->join('discount_products', 'discounts.id', '=', 'discount_products.discount_id')
                ->whereColumn('discount_products.product_id', 'products.id')
                ->where('date_start', '<=', Carbon::today()->toDateString())
                ->where('date_end', '>=', Carbon::today()->toDateString())
                ->groupBy('id')
                ->orderBy('id', 'desc')
                ->limit(1);
        }]);
    }, 't')
    ->orderByRaw('COALESCE(discount_price, price) ASC')
    ->get();

laravel产品orderByRaw COALESCE（折扣价格，价格），折扣价格未定义

1 个答案: