mysql一次查詢，返回多個統計結果

1.sum(if)

select
sum(if(status=1,1,0)) as s1_count,
sum(if(status=2,1,0)) as s2_count
from order;

2.count()

select
count(status=1 or null) as s1_count,
count(status=2 or null) as s2_count
from order;

注意：count是返回匹配條件的行數，只要有值就會算進去，所以這里不符合條件的算作Null