Stddevw_samp Function

The stddevw_samp function returns the weighted standard deviation of the sample for a set of values.

formula

The syntax of the stddevw_samp function is

stddevw_samp(x[,w])

x are the values for which the standard deviation of the sample shall be calculated.
Null values are ignored.
If the number of values is zero, the function returns null.
w are the weights. If no value is provided the weight is assumed to be 1.

Example

SELECT country, stddevw_samp(price)
  FROM sales
  GROUP BY country;