| AVG(expression) | the average (arithmetic mean) of all input values | Finding the average value is available on the following data types: smallint, integer, bigint, real, double precision, numeric, interval. The result is of type numeric for any integer type input, double precision for floating-point input, otherwise the same as the input data type. |
count(*) | number of input values | The return value is of type bigint. |
count(expression) | Counts the input values for which the value of expression is not NULL. | The return value is of type bigint. |
max(expression) | the maximum value of expression across all input values | Available for all numeric, string, and date/time types. The result has the same type as the input expression. |
min(expression) | the minimum value of expression across all input values | Available for all numeric, string, and date/time types. The result has the same type as the input expression. |
stddev(expression) | the sample standard deviation of the input values | Finding the standard deviation is available on the following data types: smallint, integer, bigint, real, double precision, numeric. The result is of type double precision for floating-point input, otherwise numeric. |
sum(expression) | sum of expression across all input values | Summation is available on the following data types: smallint, integer, bigint, real, double precision, numeric, interval. The result is of type bigint for smallint or integer input, numeric for bigint input, double precision for floating-point input, otherwise the same as the input data type. |
variance(expression) | the sample variance of the input values | The variance is the square of the standard deviation. The supported data types and result types are the same as for standard deviation. |
