Mysql 关于多个计数列和分组依据的sql查询帮助

我有下表：

id | status | school | name
----------------------------
0  | fail   | skool1 | dan
1  | fail   | skool1 | steve
2  | pass   | skool2 | joe
3  | fail   | skool2 | aaron

我想要一个能给我答案的结果

school | fail | pass  
---------------------
skool1 | 2    | 0   
skool2 | 1    | 1    

我有这个但是很慢

SELECT s.school, (

SELECT COUNT( * ) 
FROM school
WHERE name = s.name
AND status = 'fail'
) AS fail, (

SELECT COUNT( * ) 
FROM school
WHERE name = s.name
AND status = 'pass'
) AS pass,

FROM Students s
GROUP BY s.school

---

建议？

像这样的建议应该会奏效：

SELECT 
    school,
    SUM(CASE WHEN status = 'fail' THEN 1 ELSE 0 END) as [fail],
    SUM(CASE WHEN status = 'pass' THEN 1 ELSE 0 END) as [pass]
FROM Students
GROUP BY school
ORDER BY school

编辑
差点忘了，但您也可以这样编写查询：

SELECT 
    school,
    COUNT(CASE WHEN status = 'fail' THEN 1 END) as [fail],
    COUNT(CASE WHEN status = 'pass' THEN 1 END) as [pass]
FROM Students
GROUP BY school
ORDER BY school

我不确定第二个查询是否有任何性能优势。我的猜测是，如果有，它可能非常小。我倾向于使用第一个查询，因为我认为它更清晰，但两者都应该有效。此外，我手头没有MySql实例可供测试，但根据@Johan的说法，ORDERBY子句是不必要的

SELECT q.school, q.fail, q.failpass-q.fail as pass
FROM
  (
  SELECT s.school, sum(if(status = 'fail',1,0)) as fail, count(*) as failpass
  FROM students s
  GROUP BY s.school
  ) q

这样您就可以保存一个条件和。
在MySQL中，

groupby

已经对结果排序，因此不需要单独的

orderby