从当前状态查询 MySQL 中获取总计数答案

【问题标题】：Get Total Count from Current Status Query MySQL从当前状态查询 MySQL 中获取总计数
【发布时间】：2019-02-13 07:27:23
【问题描述】：

我在计算 mysql 查询当前状态的总数据时遇到问题。

简单地说，我有 3 个相互关联的表。

m_shift_schedule     site_shift_schedule      m_ticket
================     ===================     ============
* shift_id   ======>  * shift_id             * ticket_id
* start_time          * shift_date           * ticket_status
* end_time            * user_id   ========>  * ticket_served_by

我的查询：

SELECT user_id,
case when count(m_ticket.ticket_served_by)<2 then 'idle' 
     when count(m_ticket.ticket_served_by)=2 then 'Busy' 
     when count(m_ticket.ticket_served_by)>2 then 'Overload' end as status
FROM site_shift_schedule
LEFT JOIN m_shift_schedule ON site_shift_schedule.shift_id = m_shift_schedule.shift_id
LEFT JOIN m_ticket ON site_shift_schedule.user_id=m_ticket.ticket_served_by
WHERE site_shift_schedule.shift_date =  '2019-02-11' and m_ticket.ticket_status in (4,5,6)
AND CURRENT_TIME > start_time and CURRENT_TIME < end_time
group by user_id

我上面查询的输出：

user_id                           Status
=============================   ============
ismail.rahman.saanin@random.co     Idle
lutfi.aldi.nugroho@random.co       Busy

还有一个问题，如果我想显示输出变成这样，我应该怎么做：

 Status              Total
==================================
 Idle                 1
 Busy                 1

【问题讨论】：

标签： mysql sql database database-design database-connection

【解决方案1】：

您可以在下面尝试 - 使用子查询

select status,count(user_id) as total
from
(
SELECT user_id,
case when count(m_ticket.ticket_served_by)<2 then 'idle' 
     when count(m_ticket.ticket_served_by)=2 then 'Busy' 
     when count(m_ticket.ticket_served_by)>2 then 'Overload' end as status
FROM site_shift_schedule
LEFT JOIN m_shift_schedule ON site_shift_schedule.shift_id = m_shift_schedule.shift_id
LEFT JOIN m_ticket ON site_shift_schedule.user_id=m_ticket.ticket_served_by
WHERE site_shift_schedule.shift_date =  '2019-02-11' and m_ticket.ticket_status in (4,5,6)
AND CURRENT_TIME > start_time and CURRENT_TIME < end_time
group by user_id
)A group by status

【讨论】：

【解决方案2】：

group by 中的用例

SELECT 
case when count(m_ticket.ticket_served_by)<2 then 'idle' 
     when count(m_ticket.ticket_served_by)=2 then 'Busy' 
     when count(m_ticket.ticket_served_by)>2 then 'Overload' end as status,
     count(*) as total
FROM site_shift_schedule
LEFT JOIN m_shift_schedule ON site_shift_schedule.shift_id = m_shift_schedule.shift_id
LEFT JOIN m_ticket ON site_shift_schedule.user_id=m_ticket.ticket_served_by
WHERE site_shift_schedule.shift_date =  '2019-02-11' and m_ticket.ticket_status in (4,5,6)
AND CURRENT_TIME > start_time and CURRENT_TIME < end_time
group by  case when count(m_ticket.ticket_served_by)<2 then 'idle' 
     when count(m_ticket.ticket_served_by)=2 then 'Busy' 
     when count(m_ticket.ticket_served_by)>2 then 'Overload' end

【讨论】：

请您分享小提琴，因为我认为它不会起作用，因为 group by 子句中缺少 user_id。
@aldi 你检查了吗？