如何計算MySQL中的解析時間？

Question

我在下面的表格數據：

TicketID Status Datetime 
25   Open  2016-07-21 11:46:40 
25   Open  2016-07-22 09:42:40 
25   Closed 2016-07-22 09:46:40 
25   Open  2016-07-23 08:42:40 
25   Open  2016-07-24 08:46:40 
25   Open  2016-07-24 09:26:40 
25   Closed 2016-07-25 11:46:40 

我想計算如下：

（（2016年7月22日9時46分四十秒 - 2016年7月21日11:46： 40）+（2016-07-25 11:46:40 - 2016-07-23 08:42:40））/ 2。

Answer 1

這是一個想法：對於每個「打開」獲得下一個「關閉」。然後只選擇「關閉」的值，並將最小值打開以確定時間長度。所以，下面得到你想要的時間對：

select close_datetime, min(datetime) as open_datetime 
from (select t.*, 
      (select t2.DateTime 
       from t t2 
       where t2.status = 'Closed' and t2.DateTime > t.DateTime 
      ) as close_datetime 
     from t 
     where status = 'Open' 
    ) t 
group by close_datetime; 

然後你可以得到差異的總和。這得到的值在幾秒鐘內：

select sum(timestampdiff(second, clsoe_datetime, open_datetime) as num_seconds 
from (select close_datetime, min(datetime) as open_datetime 
     from (select t.*, 
        (select t2.DateTime 
        from t t2 
        where t2.status = 'Closed' and t2.DateTime > t.DateTime 
        ) as close_datetime 
      from t 
      where status = 'Open' 
      ) t 
     group by close_datetime 
    ) t 

Answer 2

這似乎對我好。

set @x=now(), @y=-1; 

select 
    avg(timestampdiff(second,prev_stat_dt,curr_stat_dt)) 
from 
    (select 
     TicketID, 
      @y prev_stat, 
      @y:=Status curr_stat, 
      @x prev_stat_dt, 
      @x:=DateTime curr_stat_dt 
    from 
     table1 
    where 
      Status in ('Open' , 'Closed')) t 
where 
    prev_stat = 'Open' and curr_stat = 'Closed';