Oracle Error QSM-02138: agg(expr) requires correspondng agg(expr*expr) function

Oracle Error Message

QSM-02138: agg(expr) requires correspondng agg(expr*expr) function

Reason for the Error

The capability in question is not supported when the materialized view uses certain aggregate functions but omits an invocation of that same aggregate function on the square of the same argument.

Solution

Add an invocation of the same aggregate function on the square of the same argument (that is, the argument multiplied by itself).