The VAR_SAMP function returns the sample variance (/n-1) of a set of numbers.
.-ALL------. >>-+-VAR_SAMP------+--(--+----------+--numeric-expression--)--->< '-VARIANCE_SAMP-' '-DISTINCT-'
If the argument is DECFLOAT(n), the result of the function is DECFLOAT(34). Otherwise, the data type of the result is double-precision floating point.
The function is applied to the set of values derived from the argument values by the elimination of null values. If DISTINCT is specified, duplicate values are eliminated.
The result can be null. If the function is applied to the empty set or a set with only one row, the result is a null value. Otherwise, the result is the variance of the values in the set.
The order in which the values are added is undefined, but every intermediate result must be within the range of the result data type.
Results
involving DECFLOAT special values: If the data type of the argument
is decimal floating-point and a special value of sNaN or -sNaN, or
both +Infinity and -Infinity are included in the aggregation, an error
or warning is returned. Otherwise, if +NaN or -NaN is found, the result
is +NaN or -NaN. If +Infinity or -Infinity is found, the result is
+Infinity or -Infinity.
Syntax alternatives: VAR_SAMP should be used for conformance to the SQL 2003 standard.
SELECT VAR_SAMP(SALARY) INTO :VARNCE FROM EMPLOYEE WHERE WORKDEPT = 'A00';Results in VARNCE being set to approximately 1 186 437 500.