timeSeriesRateToGrid

Introduced in: v25.6

Aggregate function that takes time series data as pairs of timestamps and values and calculates PromQL-like rate from this data on a regular time grid described by start timestamp, end timestamp and step. For each point on the grid the samples for calculating rate are considered within the specified time window.

Note

This function is experimental, enable it by setting allow_experimental_ts_to_grid_aggregate_function=true.

Syntax

timeSeriesRateToGrid(start_timestamp, end_timestamp, grid_step, staleness)(timestamp, value)

Parameters

start_timestamp — Specifies start of the grid. UInt32 or DateTime
end_timestamp — Specifies end of the grid. UInt32 or DateTime
grid_step — Specifies step of the grid in seconds. UInt32
staleness — Specifies the maximum staleness in seconds of the considered samples. The staleness window is a left-open and right-closed interval. UInt32

Arguments

timestamp — Timestamp of the sample. Can be individual values or arrays. UInt32 or DateTime or Array(UInt32) or Array(DateTime)
value — Value of the time series corresponding to the timestamp. Can be individual values or arrays. Float* or Array(Float*)

Returned value

Returns rate values on the specified grid. The returned array contains one value for each time grid point. The value is NULL if there are not enough samples within the window to calculate the rate value for a particular grid point. Array(Nullable(Float64))

Examples

Basic usage with individual timestamp-value pairs

WITH
    -- NOTE: the gap between 140 and 190 is to show how values are filled for ts = 150, 165, 180 according to window parameter
    [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, -- array of values corresponding to timestamps above
    90 AS start_ts,       -- start of timestamp grid
    90 + 120 AS end_ts,   -- end of timestamp grid
    15 AS step_seconds,   -- step of timestamp grid
    45 AS window_seconds  -- "staleness" window
SELECT timeSeriesRateToGrid(start_ts, end_ts, step_seconds, window_seconds)(timestamp, value)
FROM
(
    -- This subquery converts arrays of timestamps and values into rows of `timestamp`, `value`
    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]                        │
└───────────────────────────────────────────────────────────────────────────────────────┘

Using array arguments

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]                          │
└─────────────────────────────────────────────────────────────────────────────────────────┘

timeSeriesRateToGrid​

timeSeriesRateToGrid