mean aggregate function
Applies to: Databricks SQL Databricks Runtime
Returns the mean calculated from values of a group.
mean ( [ALL | DISTINCT] expr ) [FILTER ( WHERE cond ) ]
This function can also be invoked as a window function using the
expr: An expression that evaluates to a numeric.
cond: An optional boolean expression filtering the rows used for aggregation.
The result type is computed as for the arguments:
DECIMAL(p, s): The result type is a` DECIMAL(p + 4, s + 4)`. If the maximum precision for DECIMAL is reached, the increase in scale is limited to avoid loss of significant digits.
year-month interval: The result is an
INTERVAL YEAR TO MONTH.
day-time interval: The result is an
INTERVAL DAY TO SECOND.
In all other cases the result is a DOUBLE.
Nulls within the group are ignored. If a group is empty or consists only of nulls the result is NULL.
DISTINCT is specified the mean is computed after duplicates have been removed.
This function is a synonym for avg aggregate function.
In Databricks Runtime, if spark.sql.ansi.enabled is
false, an overflow returns
NULL instead of an error.