How to fix the Oracle error QSM-02175: some query block in UNION ALL MV is not fast refreshable?

In this post, you’ll learn more about the Oracle ErrorQSM-02175: some query block in UNION ALL MV is not fast refreshable with the details on why you receive this error and the possible solution to fix it.

Oracle Error Description

QSM-02175: some query block in UNION ALL MV is not fast refreshable

Reason for the Error QSM-02175: some query block in UNION ALL MV is not fast refreshable

For a materialized view with UNION ALL to be fast refreshable, each query block must conform to a fast refreshable materialized join view or materialized aggregate view.

How to fix the Error QSM-02175: some query block in UNION ALL MV is not fast refreshable ?

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

Check each query block in the UNION ALL to ensure it is either a materialized view with joins or aggregates.