postgresql - PostgreSQL 中的平均函数，容差为 5 分钟

Question

我有一个时间数据库，我想通过平均函数聚合每个 HH 瞬时值，前 5 分钟和后 5 分钟。数据采样频率为 2 分钟，数据包括时间戳和温度列。首先，代码应该从 00, 01, 02, 03, ... 24 中提取瞬时值，然后在瞬时时间之前应用 2 次观察和之后的 2 次观察。此外，在 db 中，有时分钟是奇数，有时是偶数。因此，我们同时拥有 HH-1:59 和 HH:00 。平均值取自 5 个值的平均值。date_time 列的格式是时间戳。此外，代码应该可以处理多天的数据。

样本数据：

   dt          ambtemp
       "2007-09-29 00:11:09+02";-1.87
    "2007-09-29 00:13:09+02";-1.87
    "2007-09-29 00:15:09+02";-1.8
    "2007-09-29 00:17:09+02";-1.64
    "2007-09-29 00:19:09+02";-1.6
    "2007-09-29 00:21:09+02";-1.9
    "2007-09-29 00:23:09+02";-2.08
    "2007-09-29 00:25:09+02";-1.94
    "2007-09-29 00:27:09+02";-2.12
    "2007-09-29 00:29:09+02";-1.87
    "2007-09-29 00:31:09+02";-2.18
    "2007-09-29 00:33:09+02";-1.98
    "2007-09-29 00:35:09+02";-1.73
    "2007-09-29 00:37:09+02";-1.84
    "2007-09-29 00:39:09+02";-2.04
    "2007-09-29 00:41:09+02";-1.86
    "2007-09-29 00:43:09+02";-1.94
    "2007-09-29 00:45:09+02";-1.77
    "2007-09-29 00:47:09+02";-1.78
    "2007-09-29 00:49:09+02";-1.5
    "2007-09-29 00:51:09+02";-1.46
    "2007-09-29 00:53:09+02";-1.72
    "2007-09-29 00:55:09+02";-1.67
    "2007-09-29 00:57:09+02";-1.56
    "2007-09-29 00:59:09+02";-1.69
    "2007-09-29 01:01:09+02";-1.97
    "2007-09-29 01:03:09+02";-1.79
    "2007-09-29 01:05:09+02";-1.79
    "2007-09-29 01:07:09+02";-1.84
    "2007-09-29 01:09:09+02";-1.91
    "2007-09-29 01:11:09+02";-1.87
    "2007-09-29 01:13:09+02";-1.98
    "2007-09-29 01:15:09+02";-1.83
    "2007-09-29 01:17:09+02";-1.88
    "2007-09-29 01:19:09+02";-1.88
    "2007-09-29 01:21:09+02";-1.78
    "2007-09-29 01:23:09+02";-1.78
    "2007-09-29 01:25:09+02";-1.66
    "2007-09-29 01:27:09+02";-1.7
    "2007-09-29 01:29:09+02";-1.46
    "2007-09-29 01:31:09+02";-1.36
    "2007-09-29 01:33:09+02";-1.4
    "2007-09-29 01:35:09+02";-1.34
    "2007-09-29 01:37:09+02";-1.34
    "2007-09-29 01:39:09+02";-1.3
    "2007-09-29 01:41:09+02";-1.36
    "2007-09-29 01:43:09+02";-1.4
    "2007-09-29 01:45:09+02";-1.43
    "2007-09-29 01:47:09+02";-1.38
    "2007-09-29 01:49:09+02";-1.4
    "2007-09-29 01:51:09+02";-1.42
    "2007-09-29 01:53:09+02";-1.47
    "2007-09-29 01:55:09+02";-1.66
    "2007-09-29 01:57:09+02";-1.84
    "2007-09-29 01:59:09+02";-1.92
    "2007-09-29 02:01:09+02";-1.88
    "2007-09-29 02:03:09+02";-2.11
    "2007-09-29 02:05:09+02";-1.91
    "2007-09-29 02:07:09+02";-2.04
    "2007-09-29 02:09:09+02";-1.94
    "2007-09-29 02:11:09+02";-1.92
    "2007-09-29 02:13:09+02";-1.8
    "2007-09-29 02:15:09+02";-1.74
    "2007-09-29 02:17:09+02";-1.74
    "2007-09-29 02:19:09+02";-1.76
    "2007-09-29 02:21:09+02";-1.74
    "2007-09-29 02:23:09+02";-1.8
    "2007-09-29 02:25:09+02";-1.8
    "2007-09-29 02:27:09+02";-1.8
    "2007-09-29 02:29:09+02";-1.82
    "2007-09-29 02:31:09+02";-1.9
    "2007-09-29 02:33:09+02";-1.93
    "2007-09-29 02:35:09+02";-2.06
    "2007-09-29 02:37:09+02";-2.08
    "2007-09-29 02:39:09+02";-1.95
    "2007-09-29 02:41:09+02";-1.98
    "2007-09-29 02:43:09+02";-2.32
    "2007-09-29 02:45:09+02";-1.86
    "2007-09-29 02:47:09+02";-1.97
    "2007-09-29 02:49:09+02";-1.64
    "2007-09-29 02:51:09+02";-2
    "2007-09-29 02:53:09+02";-1.48
    "2007-09-29 02:55:09+02";-1.74
    "2007-09-29 02:57:09+02";-1.85
    "2007-09-29 02:59:09+02";-1.82
    "2007-09-29 03:01:09+02";-1.82
    "2007-09-29 03:03:09+02";-1.92
    "2007-09-29 03:05:09+02";-1.8
    "2007-09-29 03:07:09+02";-1.54
    "2007-09-29 03:09:09+02";-1.36
    "2007-09-29 03:11:09+02";-1.5
    "2007-09-29 03:13:09+02";-1.59
    "2007-09-29 03:15:09+02";-1.6
    "2007-09-29 03:17:09+02";-1.58
    "2007-09-29 03:19:09+02";-1.81
    "2007-09-29 03:21:09+02";-2.16
    "2007-09-29 03:23:09+02";-1.97
    "2007-09-29 03:25:09+02";-1.94
    "2007-09-29 03:27:09+02";-2.29
    "2007-09-29 03:29:09+02";-2.46
    "2007-09-29 03:31:09+02";-2.42
    "2007-09-29 03:33:09+02";-2.34
    "2007-09-29 03:35:09+02";-2.38
    "2007-09-29 03:37:09+02";-2.44
    "2007-09-29 03:39:09+02";-2.28
    "2007-09-29 03:41:09+02";-2.24
    "2007-09-29 03:43:09+02";-2.26
    "2007-09-29 03:45:09+02";-2.05
    "2007-09-29 03:47:09+02";-2.38
    "2007-09-29 03:49:09+02";-2.24
    "2007-09-29 03:51:09+02";-2.46
    "2007-09-29 03:53:09+02";-2.22
    "2007-09-29 03:55:09+02";-2.24
    "2007-09-29 03:57:09+02";-2.2
    "2007-09-29 03:59:09+02";-2.28
    "2007-09-29 04:01:09+02";-1.86
    "2007-09-29 04:03:09+02";-1.9
    "2007-09-29 04:05:09+02";-1.98
    "2007-09-29 04:07:09+02";-1.99
    "2007-09-29 04:09:09+02";-2
    "2007-09-29 04:11:09+02";-1.98
    "2007-09-29 04:13:09+02";-2.13
    "2007-09-29 04:15:09+02";-2.11
    "2007-09-29 04:17:09+02";-2.1
    "2007-09-29 04:19:09+02";-2.28
    "2007-09-29 04:21:09+02";-2.28
    "2007-09-29 04:23:09+02";-2.44
    "2007-09-29 04:25:09+02";-2.44
    "2007-09-29 04:27:08+02";-2.2
    "2007-09-29 04:29:08+02";-2.2
    "2007-09-29 04:31:08+02";-2.11
    "2007-09-29 04:31:09+02";-2.11
    "2007-09-29 04:33:09+02";-2.3
    "2007-09-29 04:35:09+02";-2
    "2007-09-29 04:37:08+02";-1.7
    "2007-09-29 04:39:08+02";-1.43
    "2007-09-29 04:41:08+02";-1.55
    "2007-09-29 04:43:09+02";-1.43
    "2007-09-29 04:45:09+02";-1.59
    "2007-09-29 04:47:08+02";-1.58
    "2007-09-29 04:49:08+02";-1.52
    "2007-09-29 04:51:08+02";-1.5
    "2007-09-29 04:53:09+02";-1.4
    "2007-09-29 04:55:08+02";-1.46
    "2007-09-29 04:55:09+02";-1.46
    "2007-09-29 04:57:08+02";-1.5
    "2007-09-29 04:59:08+02";-1.52
    "2007-09-29 05:01:08+02";-1.64
    "2007-09-29 05:03:08+02";-1.7
    "2007-09-29 05:05:08+02";-1.7
    "2007-09-29 05:07:08+02";-1.71
    "2007-09-29 05:09:08+02";-1.96
    "2007-09-29 05:11:08+02";-2.03
    "2007-09-29 05:13:08+02";-2.18
    "2007-09-29 05:15:08+02";-2.2
    "2007-09-29 05:17:08+02";-1.91
    "2007-09-29 05:19:08+02";-2.06
    "2007-09-29 05:21:08+02";-2
    "2007-09-29 05:23:08+02";-1.92
    "2007-09-29 05:25:08+02";-2
    "2007-09-29 05:27:08+02";-1.86
    "2007-09-29 05:29:08+02";-2.08
    "2007-09-29 05:31:08+02";-2.03
    "2007-09-29 05:33:08+02";-1.83
    "2007-09-29 05:35:08+02";-1.7
    "2007-09-29 05:37:08+02";-1.7
    "2007-09-29 05:39:08+02";-1.6
    "2007-09-29 05:41:08+02";-1.64
    "2007-09-29 05:43:08+02";-1.65
    "2007-09-29 05:45:08+02";-1.67
    "2007-09-29 05:47:08+02";-1.8
    "2007-09-29 05:49:08+02";-1.82
    "2007-09-29 05:51:08+02";-1.88
    "2007-09-29 05:53:08+02";-1.91
    "2007-09-29 05:55:08+02";-1.92
    "2007-09-29 05:57:08+02";-1.93
    "2007-09-29 05:59:08+02";-1.9
    "2007-09-29 06:01:08+02";-2.04
    "2007-09-29 06:03:08+02";-1.98
    "2007-09-29 06:05:08+02";-1.96
    "2007-09-29 06:07:08+02";-1.98
    "2007-09-29 06:09:08+02";-1.93
    "2007-09-29 06:11:08+02";-1.78
    "2007-09-29 06:13:08+02";-1.73
    "2007-09-29 06:15:08+02";-1.76
    "2007-09-29 06:17:08+02";-1.67
    "2007-09-29 06:19:08+02";-1.68
    "2007-09-29 06:21:08+02";-1.38
    "2007-09-29 06:23:08+02";-1.33
    "2007-09-29 06:25:07+02";-1.31
    "2007-09-29 06:27:08+02";-1.34
    "2007-09-29 06:29:08+02";-1.28
    "2007-09-29 06:31:08+02";-1.28
    "2007-09-29 06:33:07+02";-1.51
    "2007-09-29 06:35:08+02";-1.76
    "2007-09-29 06:37:08+02";-1.84
    "2007-09-29 06:39:08+02";-1.89
    "2007-09-29 06:41:08+02";-1.98
    "2007-09-29 06:43:08+02";-2
    "2007-09-29 06:45:08+02";-2
    "2007-09-29 06:47:08+02";-1.96
    "2007-09-29 06:49:08+02";-1.92
    "2007-09-29 06:51:08+02";-1.88
    "2007-09-29 06:53:07+02";-1.79
    "2007-09-29 06:55:07+02";-1.73
    "2007-09-29 06:57:08+02";-1.7
    "2007-09-29 06:59:07+02";-1.72
    "2007-09-29 07:01:08+02";-1.74
    "2007-09-29 07:03:08+02";-1.8
    "2007-09-29 07:05:08+02";-1.8
    "2007-09-29 07:07:08+02";-1.84
    "2007-09-29 07:09:08+02";-1.88
    "2007-09-29 07:11:08+02";-1.89
    "2007-09-29 07:13:08+02";-1.92
    "2007-09-29 07:15:08+02";-1.92
    "2007-09-29 07:17:08+02";-1.96
    "2007-09-29 07:19:07+02";-1.98
    "2007-09-29 07:21:08+02";-2
    "2007-09-29 07:23:07+02";-1.96
    "2007-09-29 07:25:08+02";-1.94
    "2007-09-29 07:27:08+02";-1.92
    "2007-09-29 07:29:07+02";-1.92
    "2007-09-29 07:31:08+02";-1.92
    "2007-09-29 07:33:08+02";-1.92
    "2007-09-29 07:35:08+02";-1.94
    "2007-09-29 07:37:08+02";-1.9
    "2007-09-29 07:39:08+02";-1.92
    "2007-09-29 07:41:08+02";-1.9
    "2007-09-29 07:43:07+02";-1.9
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    "2007-09-29 07:47:08+02";-1.85
    "2007-09-29 07:49:08+02";-1.86
    "2007-09-29 07:51:07+02";-1.87
    "2007-09-29 07:53:08+02";-1.72
    "2007-09-29 07:55:08+02";-1.55
    "2007-09-29 07:57:08+02";-1.52
    "2007-09-29 07:59:08+02";-1.53
    "2007-09-29 08:01:08+02";-1.54
    "2007-09-29 08:03:08+02";-1.6
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    "2007-09-29 08:13:08+02";-1.96
    "2007-09-29 08:15:09+02";-1.88
    "2007-09-29 08:17:08+02";-1.44
    "2007-09-29 08:19:08+02";-1.34
    "2007-09-29 08:21:08+02";-1.22
    "2007-09-29 08:23:08+02";-1.34
    "2007-09-29 08:25:09+02";-1.24
    "2007-09-29 08:27:09+02";-0.66
    "2007-09-29 08:29:09+02";-0.98
    "2007-09-29 08:31:09+02";-1.1
    "2007-09-29 08:33:08+02";0.1
    "2007-09-29 08:35:09+02";0.27
    "2007-09-29 08:37:09+02";-0.14
    "2007-09-29 08:39:08+02";-0.52
    "2007-09-29 08:41:08+02";-1
    "2007-09-29 08:43:08+02";-0.58
    "2007-09-29 08:45:08+02";-0.7
    "2007-09-29 08:47:08+02";-0.6
    "2007-09-29 08:49:08+02";-0.87
    "2007-09-29 08:51:08+02";-0.44
    "2007-09-29 08:53:08+02";-0.69
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    "2007-09-29 08:57:08+02";0.12
    "2007-09-29 08:59:08+02";-0.37
    "2007-09-29 09:01:08+02";0.32
    "2007-09-29 09:03:07+02";0.04
    "2007-09-29 09:05:07+02";0.3
    "2007-09-29 09:07:07+02";0.32
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    "2007-09-29 09:11:07+02";-0.07
    "2007-09-29 09:13:07+02";0.11
    "2007-09-29 09:15:07+02";0.34
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    "2007-09-29 09:23:07+02";-0.57
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    "2007-09-29 09:31:07+02";-0.77
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    "2007-09-29 09:37:07+02";0.1
    "2007-09-29 09:39:07+02";0.05
    "2007-09-29 09:41:07+02";0.18
    "2007-09-29 09:43:07+02";1.2
    "2007-09-29 09:45:07+02";1.84
    "2007-09-29 09:47:07+02";0.93
    "2007-09-29 09:49:07+02";0.58
    "2007-09-29 09:51:07+02";-0.22
    "2007-09-29 09:53:07+02";0.09
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    "2007-09-29 09:57:07+02";1.4
    "2007-09-29 09:59:07+02";1.38
    "2007-09-29 10:01:07+02";2
    "2007-09-29 10:03:07+02";2.16
    "2007-09-29 10:05:07+02";2.48
    "2007-09-29 10:07:07+02";2.8
    "2007-09-29 10:09:07+02";1.66
    "2007-09-29 10:11:07+02";1.56
    "2007-09-29 10:13:07+02";1.49
    "2007-09-29 10:15:07+02";0.86
    "2007-09-29 10:17:07+02";1.37
    "2007-09-29 10:19:07+02";1.16
    "2007-09-29 10:21:07+02";1.16
    "2007-09-29 10:23:07+02";1.6
    "2007-09-29 10:25:07+02";0.84
    "2007-09-29 10:27:07+02";2.14
    "2007-09-29 10:29:07+02";2.25
    "2007-09-29 10:31:07+02";2.25
    "2007-09-29 10:33:07+02";2.12
    "2007-09-29 10:35:07+02";1.68
    "2007-09-29 10:37:07+02";2.14
    "2007-09-29 10:39:07+02";1.1
    "2007-09-29 10:41:07+02";1.23
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    "2007-09-29 10:45:07+02";1.78
    "2007-09-29 10:47:07+02";1.36
    "2007-09-29 10:49:07+02";2.26
    "2007-09-29 10:51:07+02";1.8
    "2007-09-29 10:53:07+02";2.08
    "2007-09-29 10:55:07+02";1.96
    "2007-09-29 10:57:07+02";2.46
    "2007-09-29 10:59:07+02";2.69
    "2007-09-29 11:01:07+02";2.24
    "2007-09-29 11:03:07+02";1.59
    "2007-09-29 11:05:07+02";1.74
    "2007-09-29 11:07:07+02";1.38
    "2007-09-29 11:09:07+02";1.97
    "2007-09-29 11:11:07+02";2.06
    "2007-09-29 11:13:07+02";1.64
    "2007-09-29 11:15:07+02";2.22
    "2007-09-29 11:17:07+02";3.07
    "2007-09-29 11:19:07+02";1.98
    "2007-09-29 11:21:07+02";2.88
    "2007-09-29 11:23:07+02";2.9
    "2007-09-29 11:25:07+02";1.62
    "2007-09-29 11:27:07+02";1.79
    "2007-09-29 11:29:07+02";2.7
    "2007-09-29 11:31:07+02";1.96
    "2007-09-29 11:33:07+02";2.9
    "2007-09-29 11:35:07+02";2.76
    "2007-09-29 11:37:07+02";2.08
    "2007-09-29 11:39:07+02";2.88
    "2007-09-29 11:41:07+02";2.55
    "2007-09-29 11:43:07+02";2.49
    "2007-09-29 11:45:07+02";2.52
    "2007-09-29 11:47:07+02";2.68
    "2007-09-29 11:49:07+02";3.1
    "2007-09-29 11:51:07+02";3.72
    "2007-09-29 11:53:07+02";2.94
    "2007-09-29 11:55:07+02";3.86
    "2007-09-29 11:57:07+02";3.76
    "2007-09-29 11:59:07+02";2.8
    "2007-09-29 12:01:07+02";2.28
    "2007-09-29 12:03:07+02";2.8
    "2007-09-29 12:05:07+02";3.1
    "2007-09-29 12:07:07+02";2.63
    "2007-09-29 12:09:07+02";2.76
    "2007-09-29 12:11:07+02";4.02
    "2007-09-29 12:13:07+02";3.47
    "2007-09-29 12:15:07+02";3.2
    "2007-09-29 12:17:07+02";2.65
    "2007-09-29 12:19:07+02";4.11
    "2007-09-29 12:21:07+02";2.66
    "2007-09-29 12:23:07+02";4.34
    "2007-09-29 12:25:07+02";4.1
    "2007-09-29 12:27:07+02";4.17
    "2007-09-29 12:29:07+02";3.16
    "2007-09-29 12:31:07+02";3.98
    "2007-09-29 12:33:07+02";3.72
    "2007-09-29 12:35:07+02";3.66
    "2007-09-29 12:37:07+02";3.26
    "2007-09-29 12:39:07+02";4.5
    "2007-09-29 12:41:07+02";3.94
    "2007-09-29 12:43:07+02";4.11
    "2007-09-29 12:45:07+02";3.89
    "2007-09-29 12:47:06+02";3.22
    "2007-09-29 12:49:06+02";4.26
    "2007-09-29 12:51:06+02";4.98
    "2007-09-29 12:53:06+02";4.46
    "2007-09-29 12:55:06+02";4.86
    "2007-09-29 12:57:07+02";3.91
    "2007-09-29 12:59:07+02";3.56
    "2007-09-29 13:01:07+02";5.27
    "2007-09-29 13:03:07+02";4.12
    "2007-09-29 13:05:07+02";5.07
    "2007-09-29 13:07:06+02";4.16
    "2007-09-29 13:09:06+02";4.56
    "2007-09-29 13:11:06+02";4.24
    "2007-09-29 13:13:06+02";4.34
    "2007-09-29 13:15:06+02";4.63
    "2007-09-29 13:17:06+02";4.68
    "2007-09-29 13:19:06+02";3.71
    "2007-09-29 13:21:06+02";3.79
    "2007-09-29 13:23:06+02";4.61
    "2007-09-29 13:25:06+02";4.95
    "2007-09-29 13:27:06+02";4.66
    "2007-09-29 13:29:06+02";4.32
    "2007-09-29 13:31:06+02";3.98
    "2007-09-29 13:33:06+02";5.43
    "2007-09-29 13:35:06+02";4.38
    "2007-09-29 13:37:06+02";4.39
    "2007-09-29 13:39:06+02";4.7
    "2007-09-29 13:41:06+02";4.34
    "2007-09-29 13:43:06+02";5.56
    "2007-09-29 13:45:06+02";4.61
    "2007-09-29 13:47:06+02";4.58
    "2007-09-29 13:49:06+02";4.81
    "2007-09-29 13:51:06+02";5.04
    "2007-09-29 13:53:06+02";5.74
    "2007-09-29 13:55:06+02";4.92
    "2007-09-29 13:57:06+02";4.65
    "2007-09-29 13:59:06+02";5.08
    "2007-09-29 14:01:06+02";4.9
    "2007-09-29 14:03:06+02";4.34
    "2007-09-29 14:05:06+02";5.42
    "2007-09-29 14:07:06+02";5.58
    "2007-09-29 14:09:06+02";4.98
    "2007-09-29 14:11:06+02";4.91
    "2007-09-29 14:13:06+02";5.44
    "2007-09-29 14:15:06+02";4.62
    "2007-09-29 14:17:06+02";5.36
    "2007-09-29 14:19:06+02";4.56
    "2007-09-29 14:21:06+02";4.77
    "2007-09-29 14:23:06+02";4.88
    "2007-09-29 14:25:06+02";4.29
    "2007-09-29 14:27:06+02";4.43
    "2007-09-29 14:29:06+02";4.78
    "2007-09-29 14:31:06+02";5.06
    "2007-09-29 14:33:06+02";4.83
    "2007-09-29 14:35:06+02";4.44
    "2007-09-29 14:37:06+02";5.48
    "2007-09-29 14:39:06+02";4.9
    "2007-09-29 14:41:06+02";4.42
    "2007-09-29 14:43:06+02";4.82
    "2007-09-29 14:45:06+02";4.9
    "2007-09-29 14:47:06+02";4.76
    "2007-09-29 14:49:06+02";5.48
    "2007-09-29 14:51:06+02";5.48
    "2007-09-29 14:53:06+02";5.46
    "2007-09-29 14:55:06+02";5.54
    "2007-09-29 14:57:06+02";5.53
    "2007-09-29 14:59:06+02";5.5
    "2007-09-29 15:01:06+02";5.33
    "2007-09-29 15:03:06+02";6.18
    "2007-09-29 15:05:06+02";4.91
    "2007-09-29 15:07:06+02";5.08
    "2007-09-29 15:09:06+02";4.71
    "2007-09-29 15:11:06+02";4.49
    "2007-09-29 15:13:06+02";5.47
    "2007-09-29 15:15:06+02";4.58
    "2007-09-29 15:17:06+02";4.75
    "2007-09-29 15:19:06+02";5.46
    "2007-09-29 15:21:06+02";5.39
    "2007-09-29 15:23:06+02";5.59
    "2007-09-29 15:25:06+02";5.76
    "2007-09-29 15:27:06+02";5.08
    "2007-09-29 15:29:06+02";5.96
    "2007-09-29 15:31:06+02";4.9
    "2007-09-29 15:33:06+02";5.36
    "2007-09-29 15:35:06+02";5.08
    "2007-09-29 15:37:06+02";5.93
    "2007-09-29 15:39:06+02";5.34
    "2007-09-29 15:41:06+02";5.24
    "2007-09-29 15:43:06+02";5.78
    "2007-09-29 15:45:06+02";6.58
    "2007-09-29 15:47:06+02";6.09
    "2007-09-29 15:49:06+02";5.4
    "2007-09-29 15:51:06+02";6.18
    "2007-09-29 15:53:06+02";5.79
    "2007-09-29 15:55:06+02";5.36
    "2007-09-29 15:57:06+02";5.8
    "2007-09-29 15:59:07+02";6.06
    "2007-09-29 16:01:06+02";5.7
    "2007-09-29 16:03:07+02";5.58
    "2007-09-29 16:05:07+02";6.5
    "2007-09-29 16:07:07+02";5.83
    "2007-09-29 16:09:07+02";5.54
    "2007-09-29 16:11:06+02";5.8
    "2007-09-29 16:13:06+02";6.03
    "2007-09-29 16:15:06+02";5.54
    "2007-09-29 16:17:07+02";5.56
    "2007-09-29 16:19:07+02";6.04
    "2007-09-29 16:21:07+02";5.74
    "2007-09-29 16:23:06+02";5.4
    "2007-09-29 16:25:07+02";6.39
    "2007-09-29 16:27:07+02";6.64
    "2007-09-29 16:29:07+02";6.3
    "2007-09-29 16:31:07+02";5.86
    "2007-09-29 16:33:07+02";5.62
    "2007-09-29 16:35:07+02";6.29
    "2007-09-29 16:37:07+02";5.24
    "2007-09-29 16:39:07+02";5.92
    "2007-09-29 16:41:07+02";5.68
    "2007-09-29 16:43:07+02";6.2
    "2007-09-29 16:45:07+02";6.53
    "2007-09-29 16:47:06+02";5.44
    "2007-09-29 16:49:06+02";5.58
    "2007-09-29 16:51:07+02";4.68
    "2007-09-29 16:53:07+02";6.36
    "2007-09-29 16:55:07+02";5.46
    "2007-09-29 16:57:06+02";5.4
    "2007-09-29 16:59:06+02";5.84
    "2007-09-29 17:01:06+02";6.12
    "2007-09-29 17:03:06+02";6.28
    "2007-09-29 17:05:06+02";5.48
    "2007-09-29 17:07:06+02";4.67
    "2007-09-29 17:09:06+02";4.69
    "2007-09-29 17:11:06+02";4.36
    "2007-09-29 17:13:06+02";4.6
    "2007-09-29 17:15:06+02";4.86
    "2007-09-29 17:17:06+02";4.52
    "2007-09-29 17:19:06+02";4.04
    "2007-09-29 17:21:06+02";3.98
    "2007-09-29 17:23:06+02";3.8
    "2007-09-29 17:25:06+02";3.76
    "2007-09-29 17:27:06+02";3.44
    "2007-09-29 17:29:06+02";3.44
    "2007-09-29 17:31:06+02";3.45
    "2007-09-29 17:33:06+02";3.64
    "2007-09-29 17:35:06+02";3.62
    "2007-09-29 17:37:06+02";3.43
    "2007-09-29 17:39:06+02";3.52
    "2007-09-29 17:41:06+02";3.31
    "2007-09-29 17:43:06+02";3.13
    "2007-09-29 17:45:06+02";3.21
    "2007-09-29 17:47:06+02";3.26
    "2007-09-29 17:49:06+02";3.17
    "2007-09-29 17:51:06+02";3.05
    "2007-09-29 17:53:06+02";2.86
    "2007-09-29 17:55:06+02";2.84
    "2007-09-29 17:57:06+02";2.79
    "2007-09-29 17:59:06+02";2.6
    "2007-09-29 18:01:06+02";2.54
    "2007-09-29 18:03:06+02";2.51
    "2007-09-29 18:05:06+02";2.54
    "2007-09-29 18:07:06+02";2.6
    "2007-09-29 18:09:06+02";2.5
    "2007-09-29 18:11:06+02";2.25
    "2007-09-29 18:13:06+02";2.26
    "2007-09-29 18:15:06+02";2.28
    "2007-09-29 18:17:06+02";1.95
    "2007-09-29 18:19:06+02";1.9
    "2007-09-29 18:21:06+02";1.8
    "2007-09-29 18:23:06+02";1.78
    "2007-09-29 18:25:06+02";1.56
    "2007-09-29 18:27:06+02";1.59
    "2007-09-29 18:29:06+02";1.55
    "2007-09-29 18:31:06+02";1.52
    "2007-09-29 18:33:06+02";1.48
    "2007-09-29 18:35:06+02";1.5
    "2007-09-29 18:37:06+02";1.44
    "2007-09-29 18:39:06+02";1.36
    "2007-09-29 18:41:06+02";1.34
    "2007-09-29 18:43:06+02";1.26
    "2007-09-29 18:45:06+02";1.2
    "2007-09-29 18:47:06+02";1.28
    "2007-09-29 18:49:06+02";1.34
    "2007-09-29 18:51:06+02";1.29
    "2007-09-29 18:53:06+02";1.36
    "2007-09-29 18:55:06+02";1.44
    "2007-09-29 18:57:06+02";1.43
    "2007-09-29 18:59:06+02";1.73
    "2007-09-29 19:01:06+02";1.94
    "2007-09-29 19:03:06+02";1.86
    "2007-09-29 19:05:06+02";1.88
    "2007-09-29 19:07:06+02";1.78
    "2007-09-29 19:09:06+02";1.52
    "2007-09-29 19:11:06+02";1.36
    "2007-09-29 19:13:06+02";1.28
    "2007-09-29 19:15:06+02";1.32
    "2007-09-29 19:17:06+02";1.24
    "2007-09-29 19:19:06+02";1.17
    "2007-09-29 19:21:06+02";1.16
    "2007-09-29 19:23:06+02";1.22
    "2007-09-29 19:25:06+02";1.18
    "2007-09-29 19:27:06+02";1.13
    "2007-09-29 19:29:06+02";1.06
    "2007-09-29 19:31:06+02";1.12
    "2007-09-29 19:33:06+02";1.16
    "2007-09-29 19:35:06+02";1.04
    "2007-09-29 19:37:06+02";0.98
    "2007-09-29 19:39:06+02";0.85
    "2007-09-29 19:41:06+02";0.85
    "2007-09-29 19:43:06+02";1.04
    "2007-09-29 19:45:06+02";0.97
    "2007-09-29 19:47:06+02";1.08
    "2007-09-29 19:49:06+02";1.2
    "2007-09-29 19:51:06+02";0.99
    "2007-09-29 19:53:06+02";0.86
    "2007-09-29 19:55:06+02";0.88
    "2007-09-29 19:57:06+02";0.86
    "2007-09-29 19:59:06+02";0.82
    "2007-09-29 20:01:06+02";0.89
    "2007-09-29 20:03:06+02";0.86
    "2007-09-29 20:05:06+02";0.94
    "2007-09-29 20:07:06+02";0.96
    "2007-09-29 20:09:06+02";1
    "2007-09-29 20:11:06+02";1.11
    "2007-09-29 20:13:06+02";1.06
    "2007-09-29 20:15:06+02";0.94
    "2007-09-29 20:17:06+02";1.18
    "2007-09-29 20:19:06+02";1.2
    "2007-09-29 20:21:06+02";1.05
    "2007-09-29 20:23:06+02";0.94
    "2007-09-29 20:25:06+02";1.02
    "2007-09-29 20:27:06+02";0.96
    "2007-09-29 20:29:06+02";0.85
    "2007-09-29 20:31:06+02";0.79
    "2007-09-29 20:33:06+02";0.92
    "2007-09-29 20:35:06+02";0.7
    "2007-09-29 20:37:06+02";0.78
    "2007-09-29 20:39:06+02";0.64
    "2007-09-29 20:41:06+02";0.54
    "2007-09-29 20:43:06+02";0.68
    "2007-09-29 20:45:06+02";0.58
    "2007-09-29 20:47:06+02";0.48
    "2007-09-29 20:49:06+02";0.46
    "2007-09-29 20:51:06+02";0.4
    "2007-09-29 20:53:06+02";0.5
    "2007-09-29 20:55:06+02";0.4
    "2007-09-29 20:57:06+02";0.49
    "2007-09-29 20:59:06+02";0.38
    "2007-09-29 21:01:06+02";0.32
    "2007-09-29 21:03:06+02";0.31
    "2007-09-29 21:05:06+02";0.22
    "2007-09-29 21:07:05+02";0.2
    "2007-09-29 21:09:05+02";0.17
    "2007-09-29 21:11:05+02";0.12
    "2007-09-29 21:13:05+02";0.22
    "2007-09-29 21:15:05+02";0.15
    "2007-09-29 21:17:05+02";0.18
    "2007-09-29 21:19:05+02";0.09
    "2007-09-29 21:21:05+02";-0.01
    "2007-09-29 21:23:05+02";-0.05
    "2007-09-29 21:25:05+02";0
    "2007-09-29 21:27:05+02";0.12
    "2007-09-29 21:29:05+02";0.09
    "2007-09-29 21:31:05+02";0.18
    "2007-09-29 21:33:05+02";0.04
    "2007-09-29 21:35:05+02";0.02
    "2007-09-29 21:37:05+02";-0.04
    "2007-09-29 21:39:05+02";-0.06
    "2007-09-29 21:41:05+02";0.06
    "2007-09-29 21:43:05+02";0.04
    "2007-09-29 21:45:05+02";0.04
    "2007-09-29 21:47:05+02";0.15
    "2007-09-29 21:49:05+02";0.22
    "2007-09-29 21:51:05+02";0.24
    "2007-09-29 21:53:05+02";0.22
    "2007-09-29 21:55:05+02";0.1
    "2007-09-29 21:57:05+02";0.11
    "2007-09-29 21:59:05+02";0.06
    "2007-09-29 22:01:05+02";0.09
    "2007-09-29 22:03:05+02";0.2
    "2007-09-29 22:05:05+02";0.11
    "2007-09-29 22:07:05+02";0.08
    "2007-09-29 22:09:05+02";0.08
    "2007-09-29 22:11:05+02";0.07
    "2007-09-29 22:13:05+02";0.06
    "2007-09-29 22:15:05+02";0.11
    "2007-09-29 22:17:05+02";0.12
    "2007-09-29 22:19:05+02";0.1
    "2007-09-29 22:21:05+02";0.19
    "2007-09-29 22:23:05+02";0.24
    "2007-09-29 22:25:05+02";0.24
    "2007-09-29 22:27:05+02";0.24
    "2007-09-29 22:29:05+02";0.22
    "2007-09-29 22:31:05+02";0.24
    "2007-09-29 22:33:05+02";0.28
    "2007-09-29 22:35:05+02";0.28
    "2007-09-29 22:37:05+02";0.26
    "2007-09-29 22:39:05+02";0.28
    "2007-09-29 22:41:05+02";0.28
    "2007-09-29 22:43:05+02";0.26
    "2007-09-29 22:45:05+02";0.27
    "2007-09-29 22:47:05+02";0.31
    "2007-09-29 22:49:05+02";0.29
    "2007-09-29 22:51:05+02";0.27
    "2007-09-29 22:53:05+02";0.3
    "2007-09-29 22:55:05+02";0.26
    "2007-09-29 22:57:05+02";0.26
    "2007-09-29 22:59:05+02";0.3
    "2007-09-29 23:01:05+02";0.3
    "2007-09-29 23:03:05+02";0.28
    "2007-09-29 23:05:05+02";0.22
    "2007-09-29 23:07:05+02";0.2
    "2007-09-29 23:09:05+02";0.16
    "2007-09-29 23:11:05+02";0.2
    "2007-09-29 23:13:05+02";0.2
    "2007-09-29 23:15:05+02";0.12
    "2007-09-29 23:17:05+02";0.08
    "2007-09-29 23:19:05+02";0.1
    "2007-09-29 23:21:05+02";0.14
    "2007-09-29 23:23:05+02";0.16
    "2007-09-29 23:25:05+02";0.27
    "2007-09-29 23:27:05+02";0.32
    "2007-09-29 23:29:05+02";0.34
    "2007-09-29 23:31:05+02";0.4
    "2007-09-29 23:33:05+02";0.37
    "2007-09-29 23:35:05+02";0.35
    "2007-09-29 23:37:05+02";0.32
    "2007-09-29 23:39:05+02";0.23
    "2007-09-29 23:41:05+02";0.26
    "2007-09-29 23:43:05+02";0.35
    "2007-09-29 23:45:05+02";0.31
    "2007-09-29 23:47:05+02";0.32
    "2007-09-29 23:49:05+02";0.3
    "2007-09-29 23:51:05+02";0.36
    "2007-09-29 23:53:05+02";0.33
    "2007-09-29 23:55:05+02";0.27
    "2007-09-29 23:57:05+02";0.27
    "2007-09-29 23:59:05+02";0.2

预期成绩：

16 点钟的小时平均值为：5.7=5.36+5.80+6.06+5.70+5.58

2007-09-29 16:00  5.7

我已经尝试过这段代码，但它不能正常工作。

select date_trunc('hour', newest_time) as average_time,  
       (oldest_temp + middle_temp + newest_temp) / 3 as average_temp 
from (  
  select
     date_trunc('hour', dt) as average_time,
     lag(dt, 2) over w as oldest_time,
     lag(dt, 1) over w as middle_time,
     dt as newest_time,
     lag(ambtemp, 2) over w as oldest_temp,
     lag(ambtemp, 1) over w as middle_temp,
     ambtemp as newest_temp   
  from n32   
    window w as (order by dt) 
) as s 
where oldest_time = newest_time - '4 minutes'::interval 
  and middle_time = newest_time - '2 minutes'::interval 
  and extract(minute from newest_time) in (2, 3);

score 1 · Accepted Answer

这只是@Catcall 已经发布的内容的一个更简单的版本（正确）：

WITH h AS (
   SELECT g - interval '5m' AS lo
         ,g + interval '5m' AS hi
   FROM   generate_series('2007-09-29 15:00'::timestamp  -- abs. dt range ..
                        , '2007-09-29 18:00'::timestamp  -- from / to
                        , interval '1h') AS g
   )
SELECT lo, hi
     , to_timestamp(avg(extract(epoch FROM s.dt))) AS avg_dt
     , round(avg(s.ambtemp)::numeric, 4) AS avg_ambtemp
FROM   h
LEFT   JOIN s_25 s ON s.dt BETWEEN lo AND hi
GROUP  BY 1,2
ORDER  BY 1,2

-> sqlfiddle

如果您不想列出找不到匹配行的时间，请将替换LEFT JOIN为JOIN。

score 1 · Accepted Answer

好吧，首先，您有两组完全不同的要求。这两件事不是一回事。

每小时前 5 分钟和后 5 分钟。
每小时观察 2 次，之后观察 2 次。

第二个依赖于您的采样永远不会在两分钟的采样间隔内。我不仅敢打赌有一天你的采样会在两分钟的间隔内失败，我敢打赌它已经做到了。采样可能由于多种原因而失败，但 5 分钟的时间间隔永远不会是 5 分钟的时间间隔。使用第一个，而不是第二个。

此查询每小时生成一个存储桶，并对每小时 5 分钟内的所有读数进行平均。它包括两个端点。也就是说，对于 16:00，它包括 15:55 和 16:05。

with buckets as (
  select '00:00'::time + (n || ' hours')::interval bucket
  from generate_series(0,23) n
)
select b.bucket, avg(t.observation) obs_avg
from buckets b
inner join test t 
        on test_ts::time between (bucket - interval '5' minute) 
                             and (bucket + interval '5' minute)
group by bucket;

bucket    obs_avg
--
16:00:00  5.7
17:00:00  5.82

如果你的值不是正态分布的——而且它们看起来不是正态分布的——你应该使用中位数而不是平均值。当您的值不是正态分布时，中位数是集中趋势的更好指示。您需要为此创建一个函数；PostgreSQL 没有原生的中值函数。

我的表名称是 s_25，时间日期表是 dt，变量是 ambtemp

基于那晚评论，并假设您的意思是您的时间戳列是 dt，这是我最好的猜测。

with buckets as (
  select '00:00'::time + (n || ' hours')::interval bucket
  from generate_series(0,23) n
)
select b.bucket, avg(t.ambtemp) obs_avg
from buckets b
inner join s_25 t 
        on dt::time between (bucket - interval '5' minute) 
                        and (bucket + interval '5' minute)
group by bucket

如果您要在多个日期运行此查询，仅按时加入是不够的。改用这个。CTE“even_hours”和“obs_dates”返回在“bucket_midpoints”中交叉连接的片段，以返回您感兴趣的日期的所有小时。“obs_dates”中的 WHERE 子句可防止您生成太多行。

with even_hours as (
  select '00:00'::time + (n || ' hour')::interval as obs_time
  from generate_series(0, 23) n
), 
obs_dates as (
  select distinct (dt)::date obs_date
  from s_25
  -- *This* WHERE clause keeps you from generating too many rows
  -- for the join below. You *could* select the min and max dates
  -- from your table, but you'd probably get too many rows that way.
  where dt between '2007-09-01' and '2007-09-30'
), 
bucket_midpoints as (
  select (obs_dates.obs_date || ' ' || even_hours.obs_time)::timestamp as bucket_midpoint
  from obs_dates, even_hours
)
select (bucket_midpoint - interval '5' minute) bucket_start,
       (bucket_midpoint + interval '5' minute) bucket_end,
       avg(s_25.ambtemp)
from bucket_midpoints
left join s_25
       on s_25.dt between (bucket_midpoint - interval '5' minute)
                      and (bucket_midpoint + interval '5' minute)
group by bucket_start, bucket_end
order by bucket_start, bucket_end

postgresql - PostgreSQL 中的平均函数，容差为 5 分钟

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