STDDEV

Returns the biased standard deviation (/n) of a set of numbers. The argument values must be any built-in numeric data type and the sum must be within the range of the data type of the result.

Example:

Using the EMPLOYEE table, return the standard deviation of the salaries for those employees in department A00.

   SELECT STDDEV(SALARY)
     FROM EMPLOYEE
     WHERE WORKDEPT = 'A00';

Returns 9938.00 when using the sample table.