MySql多重平均值

Question

我有一张桌子，其中我有不同类型的酒店房间的价格。 我想查询，以便我得到每个房间的平均价格，但是mySQL只给我1平方，而不是我需要的2。我的代码如下：

SELECT AVG(Price) From `Room` WHERE (Type='Double') OR (Type='single');

我想我的OR声明似乎让我感到烦恼..

Answer 1

SELECT AVG(Price), `Type`
FROM `Room`
GROUP BY `Type`

Answer 2

SELECT AVG(case when Type='Double' then Price else 0 end) as avg_double_price,
       AVG(case when Type='Single' then Price else 0 end) as avg_single_price,
       sum(Type='Double') as double_count,
       sum(Type='Single') as single_count
From `Room`