我有这些表：
如果我像这样加入他们：
SELECT DISTINCT
nms_alert.id,
nms_alert.alert_begin as dataAlert,
nms_employee_log.begin as employeeBegin,
nms_employee_log.end as employeeEnd,
nms_employee_log.zone_id,
nms_employee_log.device_type,
nms_employee_log.model,
nms_employee_log.wifi_network
FROM `nms_alert`
INNER JOIN nms_alert_not_attend on nms_alert.id = nms_alert_not_attend.nms_alert_id
INNER JOIN nms_employee_log on ( nms_employee_log.begin <= alert_begin AND nms_employee_log.end >= alert_begin )
WHERE nms_alert_not_attend.not_attend_id = 3
AND nms_alert.user_attended_id=3
AND nms_employee_log.employee_id= 11
正在提供：
id dataAlert employeeBegin employeeEnd zone_id device_type model wifi_network
62202 2019-12-13 20:31:20 2019-12-13 20:18:28 2019-12-13 20:46:42 27
62202 2019-12-13 20:31:20 2019-12-13 20:18:28 2019-12-13 20:47:04 27
62202 2019-12-13 20:31:20 2019-12-13 20:18:28 2019-12-13 20:47:04 25
62202 2019-12-13 20:31:20 2019-12-13 20:18:28 2019-12-13 20:47:04 26
62202 2019-12-13 20:31:20 2019-12-13 20:18:28 2019-12-13 20:47:04 24
62202 2019-12-13 20:31:20 2019-12-13 20:18:28 2019-12-13 20:46:42 26
62202 2019-12-13 20:31:20 2019-12-13 20:18:28 2019-12-13 20:46:41 24
62202 2019-12-13 20:31:20 2019-12-13 20:18:28 2019-12-13 20:46:41 25
55526 2019-12-03 19:11:53 2019-12-03 16:13:43 2019-12-03 19:40:59 24 samsung SM-G390F wifi
55526 2019-12-03 19:11:53 2019-12-03 16:13:43 2019-12-03 19:41:00 26 samsung SM-G390F wifi
55526 2019-12-03 19:11:53 2019-12-03 16:13:43 2019-12-03 19:40:59 25 samsung SM-G390F wifi
55526 2019-12-03 19:11:53 2019-12-03 16:13:43 2019-12-03 19:41:00 27 samsung SM-G390F wifi
53824 2019-11-28 20:36:02 2019-11-28 15:08:00 2019-11-29 14:28:07 25
53824 2019-11-28 20:36:02 2019-11-28 15:08:00 2019-11-29 14:28:07 26
53824 2019-11-28 20:36:02 2019-11-28 15:08:00 2019-11-29 14:28:07 24
53579 2019-11-27 13:29:08 2019-11-27 07:42:24 2019-11-27 14:09:45 24 samsung SM-G390F wifi
53579 2019-11-27 13:29:08 2019-11-27 07:42:24 2019-11-27 14:09:45 25 samsung SM-G390F wifi
53579 2019-11-27 13:29:08 2019-11-27 07:42:24 2019-11-27 14:09:45 26 samsung SM-G390F wifi
53437 2019-11-26 17:49:58 2019-11-26 15:17:04 2019-11-27 07:48:32 26 Xiaomi MI MAX 2 wifi
53437 2019-11-26 17:49:58 2019-11-26 15:17:04 2019-11-27 07:48:32 25 Xiaomi MI MAX 2 wifi
53437 2019-11-26 17:49:58 2019-11-26 15:17:04 2019-11-27 07:48:32 24 Xiaomi MI MAX 2 wifi
52535 2019-11-22 18:15:44 2019-11-22 13:33:31 2019-11-22 21:18:04 26 samsung SM-G390F wifi
52535 2019-11-22 18:15:44 2019-11-22 13:33:31 2019-11-22 21:18:04 24 samsung SM-G390F wifi
52535 2019-11-22 18:15:44 2019-11-22 13:33:31 2019-11-22 21:18:04 25 samsung SM-G390F wifi
52396 2019-11-21 22:34:05 2019-11-21 12:20:01 2019-11-22 08:14:38 24 samsung SM-G390F wifi
我想要类似的东西：
SELECT DISTINCT
# COUNT(accept),<-- How to find this?
# COUNT(reject),<-- How to find this?
nms_employee_log.begin,
nms_employee_log.end,
nms_employee_log.zone_id,
nms_employee_log.device_type,
nms_employee_log.model,
nms_employee_log.wifi_network
FROM nms_employee_log where employee_id= 11
如何获得COUNT(accept)和COUNT(reject)
什么是实现此目的的最佳查询？
和最佳表现？
CTE（如果您使用的是MySQL 8+）或子选择和CASE SUM，则可以做到这一点>SELECT
SUM(case when accept is not null then 1 else 0 end) as countAccept
,SUM(case when reject is not null then 1 else 0 end) as countReject
FROM (
SELECT DISTINCT
nms_alert.id as accept,
nms_alert_not_attend.nms_alert_id as reject,
nms_alert.alert_begin,
nms_employee_log.zone_id,
nms_employee_log.device_type,
nms_employee_log.model,
nms_employee_log.wifi_network
FROM `nms_alert`
INNER JOIN nms_alert_not_attend on nms_alert.id = nms_alert_not_attend.nms_alert_id
INNER JOIN nms_employee_log on ( nms_employee_log.begin <= alert_begin AND nms_employee_log.end >= alert_begin )
WHERE nms_alert_not_attend.not_attend_id = 3
AND nms_alert.user_attended_id=3
AND nms_employee_log.employee_id= 11
) s