COVAR_POP()

The COVAR_POP() function in MySQL calculates the population covariance between two sets of numeric values. Covariance enables us to measure the degree to which two variables modify together.

This function is regularly used in statistical analysis to understand relationships between variables. A positive covariance indicates that both variables tend to increase together, while a negative covariance indicates an inverse relationship.

Syntax

COVAR_POP(expression1, expression2)

• expression1: The first numeric data set.
• expression2: The second numeric data set.

Both expressions must contain the same number of rows.

Example

Suppose we have a table sales that records the number of units sold and the corresponding revenue for different products:

To calculate the population covariance between units_sold and revenue, the following query including COVAR_POP()can be used:

SELECT COVAR_POP(units_sold, revenue) AS population_covariance
FROM sales;

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The output of the above code will be as follows:

+----------------------+
| population_covariance |
+----------------------+
| 666666.6667         |
+----------------------+

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