PHP的MySQL複雜的順序按

Question

在我的SQL查詢

SELECT unit_price,price_counter FROM products

其結果顯示在表中。該表的最後一列被命名爲「價格與計數器的百分比」。在PHP該列的公式如下：

$PercentCompare = round((float)(($UnitPrice-$PriceCounter)/$UnitPrice) * 100);

現在的客戶端請求，該表是基於最後一列進行排序。如果該列也是我的products表中的字段或列，我可以輕鬆地執行ORDER BY，但該列僅在使用上述公式後纔會顯示在網頁表格中。

問題是，如果該列是計算/公式的結果，如何排序或使用ORDER BY？我正在使用準備好的聲明。我能做：

SELECT unit_price,price_counter FROM products ORDER BY round((float)((unit_price-price_counter)/unit_price) * 100)？

編輯第2次嘗試：

$InsertCalculation = ", round((float)((unit_price - price_counter)/unit_price) * 100) AS percentagecounter"; 
$QueryOrderBy = "perc_list_count"; 
$MyQuery = "SELECT itemid, address, city, state, zipcode, county, nameofowner, unit_price, price_counter, status" . $InsertCalculation . " FROM products WHERE itemid LIKE ? AND address LIKE ? AND city LIKE ? AND state LIKE ? AND zipcode LIKE ? AND county LIKE ? ORDER BY " . $QueryOrderBy . " ASC"; 

Answer 1

可以計算，然後下單。像這樣

SELECT unit_price,price_counter, 
    ROUND(((unit_price-price_counter)/unit_price) * 100) as percentage_price 
FROM products 
ORDER BY percentage_price ASC 

在這裏，你可以計算percentage_price，然後使其以通過