Returns the sum of squares of the
xExpr values of a group where
yExpr are NOT NULL.
Since: Databricks Runtime 11.0
yExpr: A numeric expression, the dependent variable.
xExpr: A numeric expression, the independent variable.
cond: An optional boolean expression filtering the rows used for the function.
The result type is DOUBLE.
Any nulls within the group are ignored. If a group is empty or consists only of nulls, the result is NULL.
DISTINCT is specified, the result is computed after duplicates are removed.
regr_sxx(y, x) is a synonym for
regr_count(y, x) * var_pop(x).