引入版本:v25.6.0
该聚合函数接收由时间戳和值组成的时间序列数据,并在由起始时间戳、结束时间戳和 step 定义的规则时间网格上,根据这些数据计算 类 PromQL rate。对于网格上的每个点,计算 rate 时会使用指定时间窗口内的样本。
此函数为 Experimental,请通过设置 allow_experimental_ts_to_grid_aggregate_function=true 启用。
语法
timeSeriesRateToGrid(start_timestamp, end_timestamp, grid_step, staleness)(timestamp, value)
参数
实参
返回值
返回指定网格上的速率值。返回的数组中,每个时间网格点对应一个值。如果在窗口内没有足够的样本来计算某个网格点的速率值,则该值为 NULL。Array(Nullable(Float64))
示例
使用单个时间戳-值对的基本用法
WITH
-- 注意:140 和 190 之间的间隔用于展示 ts = 150、165、180 时如何根据 window 参数填充值
[110, 120, 130, 140, 190, 200, 210, 220, 230]::Array(DateTime) AS timestamps,
[1, 1, 3, 4, 5, 5, 8, 12, 13]::Array(Float32) AS values, -- 与上述时间戳对应的值数组
90 AS start_ts, -- 时间戳网格的起点
90 + 120 AS end_ts, -- 时间戳网格的终点
15 AS step_seconds, -- 时间戳网格的步长
45 AS window_seconds -- "staleness" 窗口
SELECT timeSeriesRateToGrid(start_ts, end_ts, step_seconds, window_seconds)(timestamp, value)
FROM
(
-- 此子查询将时间戳数组和值数组转换为 `timestamp`、`value` 行
SELECT
arrayJoin(arrayZip(timestamps, values)) AS ts_and_val,
ts_and_val.1 AS timestamp,
ts_and_val.2 AS value
);
┌─timeSeriesRateToGrid(start_ts, end_ts, step_seconds, window_seconds)(timestamp, value)─┐
│ [NULL,NULL,0,0.06666667,0.1,0.083333336,NULL,NULL,0.083333336] │
└───────────────────────────────────────────────────────────────────────────────────────┘
使用数组类型参数
WITH
[110, 120, 130, 140, 190, 200, 210, 220, 230]::Array(DateTime) AS timestamps,
[1, 1, 3, 4, 5, 5, 8, 12, 13]::Array(Float32) AS values,
90 AS start_ts,
90 + 120 AS end_ts,
15 AS step_seconds,
45 AS window_seconds
SELECT timeSeriesRateToGrid(start_ts, end_ts, step_seconds, window_seconds)(timestamps, values);
┌─timeSeriesRateToGrid(start_ts, end_ts, step_seconds, window_seconds)(timestamps, values)─┐
│ [NULL,NULL,0,0.06666667,0.1,0.083333336,NULL,NULL,0.083333336] │
└─────────────────────────────────────────────────────────────────────────────────────────┘