elasticsearch/docs/reference/query-languages/esql/_snippets/functions/std_dev.md

STD_DEV [esql-std_dev]

Syntax

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Parameters

true Description

The standard deviation of a numeric field.

Supported types

number	result
double	double
integer	double
long	double

Examples

FROM employees
| STATS STD_DEV(height)

STD_DEV(height):double
0.20637044362020449

The expression can use inline functions. For example, to calculate the standard deviation of each employee’s maximum salary changes, first use MV_MAX on each row, and then use STD_DEV on the result

FROM employees
| STATS stddev_salary_change = STD_DEV(MV_MAX(salary_change))

stddev_salary_change:double
6.875829592924112