MySQL的：計數兩個場

Question

我有一個表，看起來像這樣：

Pizza ----|| Topping 
==================== 
Cheese--|| Olives 
==================== 
Ham-----  || Tuna 
==================== 
Cheese-- || Olives 
==================== 
Cheese-- || Tuna 
==================== 

我想獲得每種類型的比薩餅的數量，因此上表中會有一個火腿比薩餅，和2份芝士披薩（因爲奶酪+橄欖是重複的，只應計算一次）。基本上，我需要爲每兩個相同的元素和比薩組進行計數。

從查詢結果應該是：

Pizza ----|| Count 
==================== 
Cheese--|| 2 
==================== 
Ham-----  || 1 
==================== 

謝謝！

Answer 1

select Pizza, count(distinct Topping) as cnt 
from your_pizza_table 
group by Pizza 
order by cnt desc; 

Answer 2

試試這個

SELECT pizza, count(distinct pizza,topping) FROM test GROUP BY pizza;