stddev_samp aggregate function

Applies to: Databricks SQL Databricks Runtime

Returns the sample standard deviation calculated from the values of a group.

Syntax

stddev_samp ( [ALL | DISTINCT] expr ) [FILTER ( WHERE cond ) ]

This function can also be invoked as a window function using the OVER clause.

Arguments

• expr: An expression that evaluates to a numeric.
• cond: An optional Boolean expression filtering the rows used for aggregation.

Returns

A DOUBLE.

If DISTINCT is specified the function operates only on a unique set of expr values.

Examples

> SELECT stddev_samp(col) FROM VALUES (1), (2), (3), (3) AS tab(col);
 0.9574271077563381

> SELECT stddev_samp(DISTINCT col) FROM VALUES (1), (2), (3), (3) AS tab(col);
 1.0

Related

• std aggregate function
• stddev aggregate function
• stddev_pop aggregate function
• Window functions