从另一张桌子算起

Question

我有一张这样的桌子：

a。 tbl_cdr

b。 tbl_wo_notification_contacts

我想要的只是从tbl_wo_notification_contacts和tbl_cdr中计数。这是我的查询。

SELECT SUBSTRING(n.last_attempt,1,10) AS DATE, 
SUM(IF(n.STATUS=1, 1,0)) AS 'Success', 
SUM(IF(n.STATUS=2, 1,0)) AS 'Failed', 
COUNT(*) AS 'TotalCalls'
FROM tbl_wo_notification_contacts n
WHERE n.last_attempt >= '2019-05-01' AND n.last_attempt <= '2019-07-01'
GROUP BY SUBSTRING(n.last_attempt,1,10);

问题是我想添加一个名为“总持续时间”的新列，其中该列基于查询条件从tbl_cdr中进行计数。

Answer 1

将tbl_cdr按ContactsID分组以获取计数。

SELECT SUBSTRING(n.last_attempt,1,10) AS DATE, 
        SUM(IF(n.STATUS=1, 1,0)) AS 'Success', 
        SUM(IF(n.STATUS=2, 1,0)) AS 'Failed', 
        COUNT(*) AS 'TotalCalls',
        IFNULL(c.TotalDuration, 0) AS TotalDuration
FROM tbl_wo_notification_contacts n
LEFT JOIN (
    SELECT ContactID, COUNT(*) AS TotalDuration
    FROM tbl_cdr
    GROUP BY ContactID) AS c ON c.ContactID = n.id
WHERE n.last_attempt >= '2019-05-01' AND n.last_attempt <= '2019-07-01'
GROUP BY SUBSTRING(n.last_attempt,1,10);