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我需要帮助在 MySQL 5.0.77 中制作一个查询，根据下面显示的数据（办公室一天的通话量）返回并发电话呼叫的峰值数量。我只是想知道在一天中的任何特定时间同时打电话的人数最多是多少。

首先，这是 MySQL 表：

CREATE TABLE `call_log` (
`call_id` int(11) NOT NULL auto_increment,
`call_datetime` datetime default NULL,
`call_length` time default NULL,
PRIMARY KEY  (`call_id`)
)

我使用以下命令将数据加载到表中：

LOAD DATA LOCAL INFILE 'call_log_import.csv' INTO TABLE call_log FIELDS TERMINATED BY ',' LINE TERMINATED BY '\n' (call_datetime, call_length);

这是 CSV 格式的实际行数据：

2012-11-07 5:28:00,0:00:20
2012-11-07 7:04:00,0:00:20
2012-11-07 7:04:00,0:00:30
2012-11-07 7:04:00,0:00:30
2012-11-07 7:25:00,0:00:34
2012-11-07 7:25:00,0:00:37
2012-11-07 7:25:00,0:00:38
2012-11-07 7:30:00,0:00:16
2012-11-07 7:49:00,0:01:29
2012-11-07 7:55:00,0:00:43
2012-11-07 7:55:00,0:00:46
2012-11-07 7:55:00,0:00:46
2012-11-07 8:00:00,0:25:01
2012-11-07 8:00:00,0:00:35
2012-11-07 8:01:00,0:00:35
2012-11-07 8:01:00,0:00:35
2012-11-07 8:02:00,0:00:36
2012-11-07 8:02:00,0:03:03
2012-11-07 8:07:00,0:00:07
2012-11-07 8:08:00,0:00:08
2012-11-07 8:12:00,0:00:34
2012-11-07 8:12:00,0:00:44
2012-11-07 8:18:00,0:01:05
2012-11-07 8:28:00,0:01:05
2012-11-07 8:29:00,0:00:18
2012-11-07 8:31:00,0:00:05
2012-11-07 8:31:00,0:00:00
2012-11-07 8:31:00,0:00:11
2012-11-07 8:32:00,0:00:01
2012-11-07 8:32:00,0:27:26
2012-11-07 8:32:00,0:00:00
2012-11-07 8:32:00,0:00:00
2012-11-07 8:32:00,0:00:00
2012-11-07 8:32:00,0:00:38
2012-11-07 8:33:00,0:00:35
2012-11-07 8:33:00,0:00:04
2012-11-07 8:34:00,0:01:10
2012-11-07 8:35:00,0:09:44
2012-11-07 8:35:00,0:22:21
2012-11-07 8:35:00,0:00:17
2012-11-07 8:35:00,0:21:42
2012-11-07 8:35:00,0:21:46
2012-11-07 8:35:00,0:21:46
2012-11-07 8:37:00,0:00:29
2012-11-07 8:38:00,0:00:29
2012-11-07 8:39:00,0:06:50
2012-11-07 8:39:00,0:08:23
2012-11-07 8:53:00,0:05:01
2012-11-07 8:53:00,0:05:05
2012-11-07 8:53:00,0:05:05
2012-11-07 8:57:00,0:01:04
2012-11-07 9:00:00,0:29:40
2012-11-07 9:01:00,0:00:20
2012-11-07 9:01:00,0:01:27
2012-11-07 9:02:00,0:27:00
2012-11-07 9:03:00,0:26:18
2012-11-07 9:03:00,0:00:18
2012-11-07 9:09:00,0:01:16
2012-11-07 9:12:00,0:02:53
2012-11-07 9:12:00,0:01:09
2012-11-07 9:12:00,0:27:27
2012-11-07 9:14:00,0:07:13
2012-11-07 9:14:00,0:07:18
2012-11-07 9:14:00,0:07:18
2012-11-07 9:18:00,0:11:39
2012-11-07 9:18:00,0:11:55
2012-11-07 9:18:00,0:00:16
2012-11-07 9:17:00,0:12:15
2012-11-07 9:18:00,0:00:48
2012-11-07 9:18:00,0:00:52
2012-11-07 9:18:00,0:00:52
2012-11-07 9:19:00,0:01:12
2012-11-07 9:21:00,0:00:03
2012-11-07 9:22:00,0:02:41
2012-11-07 9:22:00,0:02:36
2012-11-07 9:22:00,0:02:49
2012-11-07 9:24:00,0:01:34
2012-11-07 9:25:00,0:06:10
2012-11-07 9:25:00,0:06:14
2012-11-07 9:25:00,0:06:14
2012-11-07 9:31:00,0:00:43
2012-11-07 9:33:00,0:00:03
2012-11-07 9:33:00,0:00:03
2012-11-07 9:33:00,0:00:03
2012-11-07 9:33:00,0:00:03
2012-11-07 9:33:00,0:00:03
2012-11-07 9:33:00,0:05:57
2012-11-07 9:32:00,0:00:30
2012-11-07 9:32:00,0:00:30
2012-11-07 9:32:00,0:06:28
2012-11-07 9:32:00,0:06:53
2012-11-07 9:32:00,0:00:35
2012-11-07 9:32:00,0:00:20
2012-11-07 9:32:00,0:01:04
2012-11-07 9:32:00,0:01:04
2012-11-07 9:32:00,0:00:41
2012-11-07 9:36:00,0:00:27
2012-11-07 9:37:00,0:23:53
2012-11-07 9:38:00,0:01:51
2012-11-07 9:40:00,0:06:40
2012-11-07 9:40:00,0:06:44
2012-11-07 9:40:00,0:06:44
2012-11-07 9:44:00,0:01:19
2012-11-07 9:46:00,0:00:55
2012-11-07 9:46:00,0:02:01
2012-11-07 9:47:00,0:20:00
2012-11-07 9:47:00,0:02:22
2012-11-07 9:47:00,0:07:12
2012-11-07 9:47:00,0:02:22
2012-11-07 9:47:00,0:00:13
2012-11-07 9:48:00,0:00:41
2012-11-07 9:48:00,0:01:25
2012-11-07 9:50:00,0:01:24
2012-11-07 9:52:00,0:00:06
2012-11-07 9:54:00,0:00:06
2012-11-07 9:57:00,0:00:28
2012-11-07 9:57:00,0:00:20
2012-11-07 9:57:00,0:00:48
2012-11-07 9:58:00,0:00:06
2012-11-07 9:58:00,0:00:06
2012-11-07 9:58:00,0:00:06
2012-11-07 9:58:00,0:00:06
2012-11-07 9:58:00,0:00:06
2012-11-07 9:58:00,0:06:49
2012-11-07 9:58:00,0:07:19
2012-11-07 9:58:00,0:00:30
2012-11-07 9:58:00,0:00:30
2012-11-07 9:58:00,0:07:38
2012-11-07 9:58:00,0:01:36
2012-11-07 9:59:00,0:00:59
2012-11-07 9:59:00,0:01:00
2012-11-07 10:00:00,0:17:43
2012-11-07 10:00:00,0:00:21
2012-11-07 10:00:00,1:02:29
2012-11-07 10:01:00,0:00:03
2012-11-07 10:01:00,0:00:03
2012-11-07 10:01:00,0:00:52
2012-11-07 10:01:00,0:20:23
2012-11-07 10:01:00,0:01:09
2012-11-07 10:01:00,0:00:20
2012-11-07 10:01:00,0:01:15
2012-11-07 10:02:00,0:00:01
2012-11-07 10:02:00,0:00:36
2012-11-07 10:02:00,0:00:48
2012-11-07 10:02:00,0:21:49
2012-11-07 10:03:00,0:40:24
2012-11-07 10:04:00,0:00:02
2012-11-07 10:04:00,0:00:02
2012-11-07 10:04:00,0:00:02
2012-11-07 10:04:00,0:05:59
2012-11-07 10:04:00,0:00:02
2012-11-07 10:04:00,0:00:02
2012-11-07 10:04:00,0:05:59
2012-11-07 10:03:00,0:06:20
2012-11-07 10:03:00,0:00:22
2012-11-07 10:06:00,0:20:35
2012-11-07 10:07:00,0:02:44
2012-11-07 10:08:00,0:00:01
2012-11-07 10:09:00,0:00:29
2012-11-07 10:09:00,0:01:17
2012-11-07 10:10:00,0:00:02
2012-11-07 10:11:00,0:00:02
2012-11-07 10:12:00,0:01:43
2012-11-07 10:12:00,0:24:01
2012-11-07 10:12:00,0:24:04
2012-11-07 10:12:00,0:24:04
2012-11-07 10:12:00,0:01:23
2012-11-07 10:13:00,0:03:51
2012-11-07 10:13:00,0:03:40
2012-11-07 10:14:00,0:09:52
2012-11-07 10:16:00,0:13:33
2012-11-07 10:16:00,0:13:37
2012-11-07 10:16:00,0:13:37
2012-11-07 10:21:00,0:00:20
2012-11-07 10:21:00,0:01:18
2012-11-07 10:21:00,0:01:18
2012-11-07 10:22:00,0:00:21
2012-11-07 10:22:00,0:00:32
2012-11-07 10:22:00,0:00:32
2012-11-07 10:22:00,0:04:31
2012-11-07 10:22:00,0:00:57
2012-11-07 10:23:00,0:10:23
2012-11-07 10:24:00,0:01:20
2012-11-07 10:24:00,0:01:24
2012-11-07 10:24:00,0:01:24
2012-11-07 10:25:00,0:27:34
2012-11-07 10:28:00,0:00:49
2012-11-07 10:30:00,0:01:46
2012-11-07 10:30:00,0:01:51
2012-11-07 10:30:00,0:01:51
2012-11-07 10:30:00,0:01:01
2012-11-07 10:31:00,0:00:43
2012-11-07 10:31:00,0:15:08
2012-11-07 10:33:00,0:02:37
2012-11-07 10:35:00,0:00:21
2012-11-07 10:35:00,0:01:24
2012-11-07 10:35:00,0:01:24
2012-11-07 10:37:00,0:02:07
2012-11-07 10:37:00,0:00:08
2012-11-07 10:38:00,0:00:10
2012-11-07 10:39:00,0:01:37
2012-11-07 10:39:00,0:00:21
2012-11-07 10:39:00,0:01:53
2012-11-07 10:39:00,0:00:03
2012-11-07 10:40:00,0:00:34
2012-11-07 10:41:00,0:00:00
2012-11-07 10:41:00,0:00:00
2012-11-07 10:41:00,0:00:00
2012-11-07 10:41:00,0:02:20
2012-11-07 10:45:00,0:07:57
2012-11-07 10:51:00,0:00:20
2012-11-07 10:51:00,0:00:56
2012-11-07 10:50:00,0:01:12
2012-11-07 10:50:00,0:00:04
2012-11-07 10:50:00,0:00:04
2012-11-07 10:50:00,0:00:04
2012-11-07 10:50:00,0:00:04
2012-11-07 10:50:00,0:00:04
2012-11-07 10:50:00,0:01:44
2012-11-07 10:50:00,0:00:31
2012-11-07 10:50:00,0:00:31
2012-11-07 10:49:00,0:03:05
2012-11-07 10:54:00,0:00:20
2012-11-07 10:54:00,0:01:02
2012-11-07 10:54:00,0:01:02
2012-11-07 10:55:00,0:02:08
2012-11-07 10:56:00,0:00:33
2012-11-07 10:56:00,0:00:05
2012-11-07 10:59:00,0:24:33
2012-11-07 10:59:00,0:24:37
2012-11-07 10:59:00,0:24:37
2012-11-07 11:00:00,0:29:41
2012-11-07 11:00:00,0:07:38
2012-11-07 11:00:00,0:00:51
2012-11-07 11:01:00,0:00:33
2012-11-07 11:02:00,0:28:12
2012-11-07 11:02:00,0:35:02
2012-11-07 11:02:00,0:35:05
2012-11-07 11:02:00,0:35:05
2012-11-07 11:02:00,0:21:29
2012-11-07 11:03:00,0:02:24
2012-11-07 11:03:00,0:02:28
2012-11-07 11:03:00,0:02:28
2012-11-07 11:03:00,0:00:03
2012-11-07 11:04:00,0:34:28
2012-11-07 11:04:00,0:08:20
2012-11-07 11:04:00,0:01:01
2012-11-07 11:06:00,0:16:09
2012-11-07 11:08:00,0:00:50
2012-11-07 11:11:00,0:02:08
2012-11-07 11:14:00,0:01:22
2012-11-07 11:14:00,0:01:26
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2012-11-07 11:14:00,0:00:20
2012-11-07 11:14:00,0:00:57
2012-11-07 11:14:00,0:00:57
2012-11-07 11:15:00,0:09:48
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2012-11-07 11:16:00,0:00:55
2012-11-07 11:18:00,0:00:48
2012-11-07 11:22:00,0:00:51
2012-11-07 11:22:00,0:00:51
2012-11-07 11:22:00,0:00:51
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2012-11-07 11:28:00,0:03:36
2012-11-07 11:29:00,0:13:18
2012-11-07 11:30:00,0:03:47
2012-11-07 11:30:00,0:20:44
2012-11-07 11:30:00,0:01:29
2012-11-07 11:32:00,0:00:39
2012-11-07 11:32:00,0:07:04
2012-11-07 11:35:00,0:02:04
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2012-11-07 11:37:00,0:18:14
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2012-11-07 11:41:00,0:04:48
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2012-11-07 12:00:00,0:08:56
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4

4 回答 4

3

对于日志中的每个呼叫，计算在该 call_datetime 处于活动状态的呼叫，然后找到最大值：

SELECT MAX(calls) FROM
(SELECT cl1.call_datetime, COUNT(*) AS calls
 FROM call_log cl1
 INNER JOIN call_log cl2
 ON cl1.call_datetime
 BETWEEN cl2.call_datetime  AND ADDTIME(cl2.call_datetime, cl2.call_length)
 GROUP BY cl1.call_id) AS counts;
于 2012-11-10T16:04:41.613 回答
1

SQL 小提琴演示

Demo 不包括您的所有数据（因为 sqlfiddle 上不允许使用超过 8000 个字符），但有一些示例数据

它显示了并发调用的最大计数

SELECT MAX(cnt) FROM
(SELECT cl1.b, COUNT(*) AS cnt
 FROM calls cl1
 INNER JOIN calls cl2
 ON cl1.b
 BETWEEN cl2.b  AND ADDTIME(cl2.b, cl2.c)
 GROUP BY cl1.a) AS counts;

和所有可能的计数。

SELECT cnt FROM
(SELECT cl1.b, COUNT(*) AS cnt
 FROM calls cl1
 INNER JOIN calls cl2
 ON cl1.b
 BETWEEN cl2.b  AND ADDTIME(cl2.b, cl2.c)
 GROUP BY cl1.a) AS counts;
于 2012-11-10T21:03:02.047 回答
0 
select * from   
(
   select count(*), time(call_datetime) t0 from call_log    
   group by time(call_datetime)   
)  as q0 order by q0.t0 desc;

更改group by使用date, time, hour, min, sec等。

于 2012-11-10T13:36:16.900 回答
0

尝试为每个通话开始添加 +1，为每个结束添加 -1，然后只需获取该 +1/-1 列的累积总和
***如果需要，请转换通话日期或使用您的格式：

set @from:='2015-02-01';
set @to:='2015-03-01';
set @csum:=0;
SELECT DT,CallCount, (@csum := @csum + CallCount) as cumulative_sum
FROM 
(select calldate AS DT, 1 AS CallCount
 from cdr
 where calldate between @from and @to

 union all

 select ADDDATE(calldate,INTERVAL duration SECOND) AS DT, -1 AS CallCount
 from cdr 
 where calldate between @from and @to
  ) Calls
ORDER BY 1 asc;


我在这里给出了一个答案

于 2015-02-27T13:29:16.390 回答