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Diagnosing ORA-12004 Refresh Fast Cannot be Used (Doc ID 179469.1)

Last updated on SEPTEMBER 20, 2022

Applies to:

Oracle Database - Enterprise Edition
Oracle Database Cloud Schema Service - Version N/A and later
Gen 1 Exadata Cloud at Customer (Oracle Exadata Database Cloud Machine) - Version N/A and later
Oracle Cloud Infrastructure - Database Service - Version N/A and later
Oracle Database Cloud Exadata Service - Version N/A and later
Information in this document applies to any platform.




The purpose of this article is to provide a step by step guide to diagnosing
the following error message, when users are attempting to refresh read only
or updatable materialized views / snapshots :

  ORA-12004: "REFRESH FAST cannot be used for snapshot ..." (in v8.x)
  ORA-12004: "REFRESH FAST cannot be used for materialized view ..." (in v9.x)

   Cause: The materialized view log does not exist or cannot be used.
  Action: Use just REFRESH, which will reinstantiate the entire table.
          If a materialized view log exists and the form of the materialized
          view allows the use of a materialized view log, REFRESH FAST will
          be available starting the next time the materialized view is

Article Contents

1. Possible Causes

  1.1 Materialized view does not exist
  1.2 Incorrect Privileges or Database Links
  1.3 Fast refreshable materialized views cannot contain complex queries
  1.4 Rollback / Undo segment space
  1.5 Primary Key and ROWID materialized view logs
  1.6 Master table truncation
  1.7 Materialized view log contains data prior to last refresh
  1.8 Materialized view uses synonyms or views
  1.9 Special Cases

2. Diagnostic Information

  2.1 Diagnostic Script & Sample Output
  2.2 Using DBMS_MVIEW.EXPLAIN_MVIEW to determine if a mv is fast refreshable

3. References


Troubleshooting Steps

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