Question

我试图在联接表

中使用like来计算order_registration.status

SELECT dstr_operator_master.*, 
count(order_registration.status like'%enquiry%') AS order_status, 
count(order_registration.pname) AS destiList 
FROM dstr_operator_master 
left JOIN order_registration 
ON FIND_IN_SET( order_registration.user_id , dstr_operator_master.u_id) 
WHERE dstr_operator_master.status = '1' 
and dstr_operator_master.type ='distributor' 
GROUP BY dstr_operator_master.auto_id

Answer 1

试试这个：

SELECT d.*, 
       SUM(CASE WHEN o.status LIKE '%enquiry%' THEN 1 ELSE 0 END) AS order_status, 
       COUNT(o.pname) AS destiList 
FROM   dstr_operator_master d
LEFT JOIN order_registration o ON FIND_IN_SET(o.user_id, d.u_id) 
WHERE d.status = '1' AND d.type = 'distributor' 
GROUP BY d.auto_id;

Answer 2

您的计数可能会返回相同的值，因为COUNT()计算非NULL值的数量。对于第一个，请使用SUM()代替COUNT()：

SELECT dstr_operator_master.*, 
       SUM(order_registration.status LIKE'%enquiry%') AS order_status, 
       Count(order_registration.pname)                AS destiList 
. . .

MySQL将布尔值视为数字上下文中的数字，其中true为1，false为0.这就是SUM()有效的原因。

我无法获得正确的order_status数量

2 个答案: