Oracle Error Message
QSM-02114: no GROUP BY clause, no aggregates and not >= 9.0 compatibility
Reason for the Error
The capability in question is not supported when the materialized view has no GROUP BY clause, no aggregates and compatibility mode is less than 9.0.
Solution
Re-phrase the query to avoid the include a GROUP BY clause or an aggregate function. Or set compatibility mode to 9.0 or greater.