MySQL的ORDER BY兩個字段條件

Question

我有產生由以下邏輯有序選擇查詢的問題：

SELECT * FROM Products WHERE 1 ORDER BY Stock > 0, Price DESC 

表樣品：

+---------+-------+-------+ 
| Product | Price | Stock | 
+---------+-------+-------+ 
| Car  | 3500 | 30 | 
| Boat | 7500 |  6 | 
| Bike | 150 | 220 | 
| Plane | 55000 |  0 | 
+---------+-------+-------+ 

期望的結果是，該表將被訂購價格如果庫存值大於0.

所以結果應該是：

+---------+-------+-------+ 
| Product | Price | Stock | 
+---------+-------+-------+ 
| Boat | 7500 |  6 | 
| Car  | 3500 | 30 | 
| Bike | 150 | 220 | 
| Plane | 55000 |  0 | 
+---------+-------+-------+ 

任何想法？

Answer 1

在MySQL中比較的結果是0或1。所以Stock > 0是1如果true。和1和0。因此，無論使用

ORDER BY Stock = 0 ASC, Price DESC 

或

ORDER BY Stock > 0 DESC, Price DESC 

或

ORDER BY case when Stock > 0 
       then 1 
       else 2 
     end, 
     Price DESC