How to fix the Oracle error QSM-02021: set operator encountered in mv?

In this post, you’ll learn more about the Oracle ErrorQSM-02021: set operator encountered in mv with the details on why you receive this error and the possible solution to fix it.

Oracle Error Description

QSM-02021: set operator encountered in mv

Reason for the Error QSM-02021: set operator encountered in mv

The capability in question is not supported when the materialized view uses set operators such as UNION, UNION ALL, MINUS, etc.

How to fix the Error QSM-02021: set operator encountered in mv ?

You can fix this error in Oracle by following the below steps

Re-phrase the query to avoid the use of set operators.