Oracle Error Message
ORA-12057: materialized view “string”.”string” is INVALID and must complete refresh
Reason for the Error
The status of the materialized view was INVALID and an attempt was made to fast refresh the materialized view.
Solution
Perform a complete refresh of the materialized view. Check the value of the STATUS column in dba_mviews, all_mviews, or user_mviews to verify that the materialized view is VALID after the complete refresh.