如何计算分数超过90 SQL

Question

我想在90算分数，但这个结束了。如果我的数据是

100 
45 
90 
100 

它应该显示3总行

select g.score as score 
     ,count(case when g.score>=90 then 1 else 0 end) over() as passed 
from grades g 

计数，而是它显示4

Answer 1

你要么删除ELSE一部分，所以默认为NULL和COUNT犯规次数NULL

select g.score as score 
     ,count(case when g.score>=90 then 1 end) over() as passed 
from grades g 

或更改COUNT为SUM

select g.score as score 
     ,SUM(case when g.score>=90 then 1 else 0 end) over() as passed 
from grades g 

Answer 2

只需在SUM编辑COUNT。 COUNT计数非空值，所以它甚至计数0; SUM只会'计数'非零值