covar_pop.md

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

COVAR_POP

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

{% code title="Aggregate function example" %}

SELECT COVAR_POP(transaction_count, gas_used)
FROM eth.recent_blocks

-- 31.70536771189994

{% endcode %}

{% code title="Aggregate function example using optional DISTINCT clause" %}

SELECT COVAR_POP(DISTINCT transaction_count, gas_used)
FROM eth.recent_blocks

-- 302.592806814443e

{% endcode %}

{% code title="Window function example" %}

SELECT COVAR_POP(transaction_count, gas_used)
  OVER (PARTITION BY transaction_count)
FROM eth.recent_blocks

-- 1.5543122344752192e-15

{% endcode %}

Usage Note

This function supports the use of ALL and DISTINCT:

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