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timeSeriesQuantileToGrid

Introduced in: v26.9.0 Aggregate function that takes time series data as pairs of timestamps and values and calculates the PromQL quantile_over_time function on a regular time grid described by start timestamp, end timestamp and step. For each point on the grid the samples for calculating the quantile are considered within the specified time window. The quantile is computed using the R-7 (inclusive) method, like quantileExactInclusive. NaN samples are not skipped the way quantileExactInclusive skips them: like in Prometheus they are kept and sorted before every real value, so a window of [1, NaN, 2] has median 1, and a window whose samples are all NaN gives NaN. The quantile level follows the samples as the last argument: either one number used at every grid point, or an array with one number per grid point. It must be the same in every row. Like in Prometheus, a level below 0 gives -Inf, a level above 1 gives +Inf and a NaN level gives NaN for every grid point whose window has samples.
This function is in private preview, enable it by setting enable_time_series_aggregate_functions=true.
Syntax
Parameters
  • start_timestamp — Specifies start of the grid. It can also be a fractional number, or a string containing a number or a date-time text. UInt32 or DateTime or DateTime64 or Float* or Decimal* or String
  • end_timestamp — Specifies end of the grid. It can also be a fractional number, or a string containing a number or a date-time text. UInt32 or DateTime or DateTime64 or Float* or Decimal* or String
  • grid_step — Specifies step of the grid in seconds. It can also be a fractional number, or a string containing a number or a duration like ’15s’ or ‘1m’. UInt32 or Float* or Decimal* or String
  • staleness — Specifies the maximum “staleness” in seconds of the considered samples. The staleness window is a left-open and right-closed interval. It can also be a fractional number, or a string containing a number or a duration like ’15s’ or ‘1m’. UInt32 or Float* or Decimal* or String
Arguments Returned value Returns the phi-quantile of values on the specified grid. The returned array contains one value for each time grid point. The value is NULL if there are no samples within the window for a particular grid point. Array(Nullable(Float64)) Examples
Last modified on October 7, 2026