值范围内的mysql分组 [英] mysql grouping while a value is in a range

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本文介绍了值范围内的mysql分组的处理方法，对大家解决问题具有一定的参考价值，需要的朋友们下面随着小编来一起学习吧！

问题描述

我搜索过高低，似乎找不到任何有关如何处理查询的信息.如果我提出一个愚蠢的问题，我事先表示歉意，但我确实需要一些帮助.

I have searched high and low and cannot seem to find any information about how to handle my query. I apologize in advance if I am asking a silly question, but I really need some help.

我有一系列以不同间隔记录的值.数据如下所示:

I have a series of values that are recorded at various intervals. The data looks like the following: 

 timeStamp           | RPM 
 2012-05-01 01:02:56 | 802
 2012-05-01 01:03:45 | 845
 2012-05-01 01:04:50 | 825
 2012-05-01 01:05:55 | 810
 2012-05-01 01:07:00 | 1000
 2012-05-01 01:08:03 | 1005
 2012-05-01 01:09:05 | 1145
 2012-05-01 01:10:15 | 1110
 2012-05-01 01:11:20 | 800
 2012-05-01 01:12:22 | 812
 2012-05-01 01:13:20 | 820
 2012-05-01 01:14:20 | 820
 2012-05-01 01:15:20 | 1200

示例中的RPM是引擎RPM.

The RPM in the example is engine RPM.

当RPM在800-900范围内时，我需要开始和结束时间戳记，因为这被认为是发动机空转.我还希望能够返回每个非怠速时间段的开始时间和结束时间.

I need the start and end timestamp while the RPM is in the range of 800-900, as this is considered engine idling. I would also like to be able to return the start and end time for each non-idling period.

我想要得到的结果是这样的:

The result I am trying to get would be something like: 

Period    | startTime           | endTime             | duration 
 Idle1    | 2012-05-01 01:02:56 | 2012-05-01 01:05:55 | 179 seconds 
 nonIdle1 | 2012-05-01 01:07:00 | 2012-05-01 01:10:15 | 195 seconds 
 idle2    | 2012-05-01 01:11:20 | 2012-05-01 01:14:20 | 180 seconds

感谢您的提前帮助.

谢谢

推荐答案

请尝试以下操作: http ://www.sqlfiddle.com/#！2/e9372/1

在数据库方面执行此操作的优势在于，不仅可以在PHP上使用查询，还可以在Java，C#，Python等上使用查询.并且在数据库方面快速进行查询

The advantage on doing it on DB side is you can get to use the query not only on PHP, you can also use it on Java, C#, Python, etc. And it's fast doing it on the DB side

select 
  if(idle_state = 1, 
       concat('Idle ', idle_count), 
       concat('NonIdle ', non_idle_count) ) as Period,
  startTime, endTime, duration
from
(

  select 

    @idle_count := @idle_count + if(idle_state = 1,1,0) as idle_count,
    @non_idle_count := @non_idle_count +if(idle_state = 0,1,0) as non_idle_count,

    state_group, idle_state,
    min(timeStamp) as startTime, max(timeStamp) as endTime,
    timestampdiff(second, min(timeStamp), max(timeStamp)) as duration
  from
  (
    select *,        
      @idle_state := if(rpm between 800 and 900, 1, 0) as idle_state,
      @state_group := @state_group + 
                      if(@idle_state = @prev_state,0,1) as state_group,
      @prev_state := @idle_state
    from (tbl, (select @state_group := 0 as y) as vars)
    order by tbl.timeStamp
  ) as x
  ,(select @idle_count := 0 as y, @non_idle_count := 0 as z) as vars
  group by state_group, idle_state

) as summary

输出:

|    PERIOD |                  STARTTIME |                    ENDTIME | DURATION |
|-----------|----------------------------|----------------------------|----------|
|    Idle 1 | May, 01 2012 01:02:56-0700 | May, 01 2012 01:05:55-0700 |      179 |
| NonIdle 1 | May, 01 2012 01:07:00-0700 | May, 01 2012 01:10:15-0700 |      195 |
|    Idle 2 | May, 01 2012 01:11:20-0700 | May, 01 2012 01:14:20-0700 |      180 |
| NonIdle 2 | May, 01 2012 01:15:20-0700 | May, 01 2012 01:15:20-0700 |        0 |

在此处查看查询进度: http://www.sqlfiddle.com/#！ 2/e9372/1

See the query progression here: http://www.sqlfiddle.com/#!2/e9372/1

五个步骤.

首先，将空闲状态与非空闲状态分开:

First, separate the idle from non-idle:

select *,
  @idle_state := if(rpm between 800 and 900, 1, 0) as idle_state
from (tbl, (select @state_group := 0 as y) as vars)
order by tbl.timeStamp;

输出:

|                  TIMESTAMP |  RPM | Y | IDLE_STATE |
|----------------------------|------|---|------------|
| May, 01 2012 01:02:56-0700 |  802 | 0 |          1 |
| May, 01 2012 01:03:45-0700 |  845 | 0 |          1 |
| May, 01 2012 01:04:50-0700 |  825 | 0 |          1 |
| May, 01 2012 01:05:55-0700 |  810 | 0 |          1 |
| May, 01 2012 01:07:00-0700 | 1000 | 0 |          0 |
| May, 01 2012 01:08:03-0700 | 1005 | 0 |          0 |
| May, 01 2012 01:09:05-0700 | 1145 | 0 |          0 |
| May, 01 2012 01:10:15-0700 | 1110 | 0 |          0 |
| May, 01 2012 01:11:20-0700 |  800 | 0 |          1 |
| May, 01 2012 01:12:22-0700 |  812 | 0 |          1 |
| May, 01 2012 01:13:20-0700 |  820 | 0 |          1 |
| May, 01 2012 01:14:20-0700 |  820 | 0 |          1 |
| May, 01 2012 01:15:20-0700 | 1200 | 0 |          0 |

第二，将更改分为几组:

Second, segregate the changes into groups:

select *,  
  @idle_state := if(rpm between 800 and 900, 1, 0) as idle_state,
  @state_group := @state_group + 
                  if(@idle_state = @prev_state,0,1) as state_group,
  @prev_state := @idle_state

from (tbl, (select @state_group := 0 as y) as vars)
order by tbl.timeStamp;

输出:

|                  TIMESTAMP |  RPM | Y | IDLE_STATE | STATE_GROUP | @PREV_STATE := @IDLE_STATE |
|----------------------------|------|---|------------|-------------|----------------------------|
| May, 01 2012 01:02:56-0700 |  802 | 0 |          1 |           1 |                          1 |
| May, 01 2012 01:03:45-0700 |  845 | 0 |          1 |           1 |                          1 |
| May, 01 2012 01:04:50-0700 |  825 | 0 |          1 |           1 |                          1 |
| May, 01 2012 01:05:55-0700 |  810 | 0 |          1 |           1 |                          1 |
| May, 01 2012 01:07:00-0700 | 1000 | 0 |          0 |           2 |                          0 |
| May, 01 2012 01:08:03-0700 | 1005 | 0 |          0 |           2 |                          0 |
| May, 01 2012 01:09:05-0700 | 1145 | 0 |          0 |           2 |                          0 |
| May, 01 2012 01:10:15-0700 | 1110 | 0 |          0 |           2 |                          0 |
| May, 01 2012 01:11:20-0700 |  800 | 0 |          1 |           3 |                          1 |
| May, 01 2012 01:12:22-0700 |  812 | 0 |          1 |           3 |                          1 |
| May, 01 2012 01:13:20-0700 |  820 | 0 |          1 |           3 |                          1 |
| May, 01 2012 01:14:20-0700 |  820 | 0 |          1 |           3 |                          1 |
| May, 01 2012 01:15:20-0700 | 1200 | 0 |          0 |           4 |                          0 |

第三，将它们分组，然后计算持续时间:

Third, group them, and compute the duration:

select 
  state_group, idle_state,
  min(timeStamp) as startTime, max(timeStamp) as endTime,
  timestampdiff(second, min(timeStamp), max(timeStamp)) as duration
from
(
  select *,    
    @idle_state := if(rpm between 800 and 900, 1, 0) as idle_state,
    @state_group := @state_group + 
                    if(@idle_state = @prev_state,0,1) as state_group,
    @prev_state := @idle_state
  from (tbl, (select @state_group := 0 as y) as vars)
  order by tbl.timeStamp
) as x
group by state_group, idle_state;

输出:

| STATE_GROUP | IDLE_STATE |                  STARTTIME |                    ENDTIME | DURATION |
|-------------|------------|----------------------------|----------------------------|----------|
|           1 |          1 | May, 01 2012 01:02:56-0700 | May, 01 2012 01:05:55-0700 |      179 |
|           2 |          0 | May, 01 2012 01:07:00-0700 | May, 01 2012 01:10:15-0700 |      195 |
|           3 |          1 | May, 01 2012 01:11:20-0700 | May, 01 2012 01:14:20-0700 |      180 |
|           4 |          0 | May, 01 2012 01:15:20-0700 | May, 01 2012 01:15:20-0700 |        0 |

第四，获取空闲和非空闲计数:

Fourth, get the idle and non-idle count:

select 

  @idle_count := @idle_count + if(idle_state = 1,1,0) as idle_count,
  @non_idle_count := @non_idle_count + if(idle_state = 0,1,0) as non_idle_count,

  state_group, idle_state,
  min(timeStamp) as startTime, max(timeStamp) as endTime,
  timestampdiff(second, min(timeStamp), max(timeStamp)) as duration
from
(
  select *,        
    @idle_state := if(rpm between 800 and 900, 1, 0) as idle_state,
    @state_group := @state_group + 
                    if(@idle_state = @prev_state,0,1) as state_group,
    @prev_state := @idle_state
  from (tbl, (select @state_group := 0 as y) as vars)
  order by tbl.timeStamp
) as x
,(select @idle_count := 0 as y, @non_idle_count := 0 as z) as vars
group by state_group, idle_state;

输出:

| IDLE_COUNT | NON_IDLE_COUNT | STATE_GROUP | IDLE_STATE |                  STARTTIME |                    ENDTIME | DURATION |
|------------|----------------|-------------|------------|----------------------------|----------------------------|----------|
|          1 |              0 |           1 |          1 | May, 01 2012 01:02:56-0700 | May, 01 2012 01:05:55-0700 |      179 |
|          1 |              1 |           2 |          0 | May, 01 2012 01:07:00-0700 | May, 01 2012 01:10:15-0700 |      195 |
|          2 |              1 |           3 |          1 | May, 01 2012 01:11:20-0700 | May, 01 2012 01:14:20-0700 |      180 |
|          2 |              2 |           4 |          0 | May, 01 2012 01:15:20-0700 | May, 01 2012 01:15:20-0700 |        0 |

最后，删除暂存变量:

select 
  if(idle_state = 1, 
       concat('Idle ', idle_count), 
       concat('NonIdle ', non_idle_count) ) as Period,
  startTime, endTime, duration
from
(

  select 

    @idle_count := @idle_count + if(idle_state = 1,1,0) as idle_count,
    @non_idle_count := @non_idle_count +if(idle_state = 0,1,0) as non_idle_count,

    state_group, idle_state,
    min(timeStamp) as startTime, max(timeStamp) as endTime,
    timestampdiff(second, min(timeStamp), max(timeStamp)) as duration
  from
  (
    select *,        
      @idle_state := if(rpm between 800 and 900, 1, 0) as idle_state,
      @state_group := @state_group + 
                      if(@idle_state = @prev_state,0,1) as state_group,
      @prev_state := @idle_state
    from (tbl, (select @state_group := 0 as y) as vars)
    order by tbl.timeStamp
  ) as x
  ,(select @idle_count := 0 as y, @non_idle_count := 0 as z) as vars
  group by state_group, idle_state

) as summary

输出:

|    PERIOD |                  STARTTIME |                    ENDTIME | DURATION |
|-----------|----------------------------|----------------------------|----------|
|    Idle 1 | May, 01 2012 01:02:56-0700 | May, 01 2012 01:05:55-0700 |      179 |
| NonIdle 1 | May, 01 2012 01:07:00-0700 | May, 01 2012 01:10:15-0700 |      195 |
|    Idle 2 | May, 01 2012 01:11:20-0700 | May, 01 2012 01:14:20-0700 |      180 |
| NonIdle 2 | May, 01 2012 01:15:20-0700 | May, 01 2012 01:15:20-0700 |        0 |

在此处查看查询进度: http://www.sqlfiddle.com/#!2/e9372/1

See query progression here: http://www.sqlfiddle.com/#!2/e9372/1

更新

查询可以缩短 http://www.sqlfiddle.com/#!2/418cb/1

如果您会注意到，则周期号只是串联(idle-nonIdle，idle-nonIdle等).您可以这样做:

If you will notice, the period number just come in tandem (idle-nonIdle,idle-nonIdle,and so forth). You can just do this:

select 


  case when idle_state then
     concat('Idle ', @rn := @rn + 1) 
  else
     concat('Non-idle ', @rn )
  end as Period,


  min(timeStamp) as startTime, max(timeStamp) as endTime,

  timestampdiff(second, min(timeStamp), max(timeStamp)) as duration

from
(
  select *,        
  @idle_state := if(rpm between 800 and 900, 1, 0) as idle_state,
  @state_group := @state_group + if(@idle_state = @prev_state,0,1) as state_group,
  @prev_state := @idle_state
  from (tbl, (select @state_group := 0 as y) as vars)
  order by tbl.timeStamp
) as x,
(select @rn := 0) as rx
group by state_group, idle_state

输出:

|     PERIOD |                  STARTTIME |                    ENDTIME | DURATION |
|------------|----------------------------|----------------------------|----------|
|     Idle 1 | May, 01 2012 01:02:56-0700 | May, 01 2012 01:05:55-0700 |      179 |
| Non-idle 1 | May, 01 2012 01:07:00-0700 | May, 01 2012 01:10:15-0700 |      195 |
|     Idle 2 | May, 01 2012 01:11:20-0700 | May, 01 2012 01:14:20-0700 |      180 |
| Non-idle 2 | May, 01 2012 01:15:20-0700 | May, 01 2012 01:15:20-0700 |        0 |

这篇关于值范围内的mysql分组的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！

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