Stddevw_pop Function

The stddevw_pop function returns the weighted standard deviation of the population for a set of values.


The syntax of the stddevw_pop function is


x are the values for which the standard deviation of the population 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.


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