Categories: Aggregate, Window

COVAR_POP

Returns the population covariance for non-NULL pairs across all input values.

Syntax

COVAR_POP(expression1 numeric, expression2 numeric) → double

• expression1: An expression that evaluates to a numeric type. This parameter is the dependent value.
• expression2: An expression that evaluates to a numeric type. This parameter is the independent value.

Examples

Aggregate function example

SELECT COVAR_POP(trip_distance_mi, fare_amount)
FROM Samples."samples.dremio.com"."NYC-taxi-trips"
-- 31.70536771189994

Aggregate function example using optional DISTINCT clause

SELECT COVAR_POP(DISTINCT trip_distance_mi, fare_amount)
FROM Samples."samples.dremio.com"."NYC-taxi-trips"
-- 302.59280681444307

Window function example

SELECT COVAR_POP(trip_distance_mi, fare_amount)
  OVER (PARTITION BY trip_distance_mi)
FROM Samples."samples.dremio.com"."NYC-taxi-trips"
-- 1.5543122344752192e-15

Usage Notes

This function supports the use of ALL and DISTINCT:

SELECT COVAR_POP( [ { ALL | DISTINCT } ] expression1, expression2)