Mysql 如何从“Case-When”条件计数

我希望有人能为我的案子提供帮助：

当我的sql代码中出现以下情况时，如何从我的案例中计数：

SELECT CASE WHEN datediff( b.`DATE` , A.`SUBMIT_DATE` ) >3
THEN 'NOK'
ELSE 'OK'
END AS
STATUS FROM complaint a
LEFT JOIN handling b ON a.cid = b.cid

---

应该是这样的：D哈哈：

Select status,count(*)
From 
(
SELECT CASE WHEN datediff( b.`DATE` , A.`SUBMIT_DATE` ) >3 THEN 'NOK' ELSE 'OK' END AS STATUS FROM complaint a LEFT JOIN handling b ON a.cid = b.cid
) a
Group by status

尝试下面的查询-

SELECT CASE WHEN DATEDIFF( b.`DATE` , A.`SUBMIT_DATE` ) >3 THEN 'NOK' ELSE 'OK' END AS mystatus, 
SUM(IF(DATEDIFF( b.`DATE` , A.`SUBMIT_DATE` ) >3,1,0)) AS cnt 
FROM complaint a
LEFT JOIN handling b ON a.cid = b.cid 
GROUP BY mystatus;

或者，您可以将statusOK、NOK转换为不同的列：

SELECT   
   COUNT CASE WHEN datediff( b.`DATE` , A.`SUBMIT_DATE` ) >3 THEN 1 END) AS 'NOK',
   COUNT CASE WHEN datediff( b.`DATE` , A.`SUBMIT_DATE` ) <=3 THEN 1 END) AS  'OK' 
FROM complaint a LEFT JOIN handling b ON a.cid = b.cid

按状态从投诉组中选择status，COUNT*，您是否尝试过此操作

SELECT   
   COUNT CASE WHEN datediff( b.`DATE` , A.`SUBMIT_DATE` ) >3 THEN 1 END) AS 'NOK',
   COUNT CASE WHEN datediff( b.`DATE` , A.`SUBMIT_DATE` ) <=3 THEN 1 END) AS  'OK' 
FROM complaint a LEFT JOIN handling b ON a.cid = b.cid