Returns the population variance for the data points in value_expression.
This function returns the REAL data type.
To invoke the time series version of this function, use the GROUP BY TIME clause. For more information, see Teradata Vantage™ - Time Series Tables and Operations, B035-1208.
For the VAR_POP window function that performs a group, cumulative, or moving computation, see Window Aggregate Functions.
Variance
The variance of a population is a measure of dispersion from the mean of that population.
Do not use VAR_POP unless the data points you are processing are the complete population.
Computation
When the population has no non-null data points, VAR_POP returns NULL.
Division by zero returns NULL rather than an error.
ANSI Compliance
This statement is ANSI SQL:2011 compliant.