Categories:

Data metric functions

APPROX_QUANTILE_80 (system data metric function)

Returns the approximate 80th percentile (P80) value for the specified column in a table.

This topic provides the syntax for calling the function directly. To learn how to associate the function with a table or view so it runs at regular intervals, see Associate a DMF.

Syntax

SNOWFLAKE.CORE.APPROX_QUANTILE_80(<query>)

Arguments

query

Specifies a SQL query that projects a single column.

Allowed data types

The column projected by the query must have one of the following data types:

  • FLOAT
  • NUMBER

Returns

The function returns a FLOAT value. NULL values are ignored. The function returns NULL if the column contains no non-NULL values.

Usage notes

  • The function uses APPROX_PERCENTILE, so the result is an estimate, and values between data points are interpolated linearly.

Example

Measure the approximate 80th percentile in the latency_ms column:

SELECT SNOWFLAKE.CORE.APPROX_QUANTILE_80(
  SELECT
    latency_ms
  FROM metrics.tables.requests
);