mysql - 汇总mysql中的列值

Question

我有一个包含以下数据的表“fruits”

id  a 
123 apple
223 orange
646 apple
757 banana
876 kiwi
989 orange

我想写一个 mysql 来总结“a”列的出现并将它们放入 3 个单独的桶中:一个用于苹果，一个用于橙子，其余的在“其他”下

SELECT 
     count(*) as total
     sum(if(a = 'apple',1,0)) as applecount
     , sum(if(a = 'orange',1,0)) as orangecount
     , sum(`applecount` + `orangecount` - total) as others

FROM fruits 

但是在运行查询时，给出了以下错误 字段列表中的未知列“applecount”

Answer 1

SELECT count(*) as total,
       sum(a = 'apple') as applecount,
       sum(a = 'orange') as orangecount,
       sum(a not in ('orange', 'apple')) as others
FROM fruits

SQLFiddle example