How to fix the Oracle error QSM-02176: MV with UNION ALL in a view is too complex?

In this post, you’ll learn more about the Oracle ErrorQSM-02176: MV with UNION ALL in a view is too complex with the details on why you receive this error and the possible solution to fix it.

Oracle Error Description

QSM-02176: MV with UNION ALL in a view is too complex

Reason for the Error QSM-02176: MV with UNION ALL in a view is too complex

If a materialized view has a view whose definition involves a UNION ALL query, then the materialized view’s defining query cannot have any clauses other than SELECT or FROM. Other clauses such as WHERE, HAVING, CONNECT BY, or GROUP BY are not allowed. Further more, the FROM clause should have only one item.

How to fix the Error QSM-02176: MV with UNION ALL in a view is too complex ?

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

Remove any clauses besides SELECT and FROM from the materialized view’s defining query.