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When to use unsupported parameters _corrupt_rollback_segments and others. (Doc ID 1360786.1)

Last updated on APRIL 27, 2021

Applies to:

Oracle Database - Enterprise Edition - Version to [Release 8.0.6 to 11.2]
Oracle Database Cloud Schema Service - Version N/A and later
Oracle Database Exadata Express Cloud Service - Version N/A and later
Oracle Database Exadata Cloud Machine - Version N/A and later
Oracle Database Cloud Exadata Service - Version N/A and later
Information in this document applies to any platform.


There are many documents available on the internet and other electronic source that show the use of
unsupport parameters to open a database. Two of these parameters are _OFFLINE_ROLLBACK_SEGMENTS and



 _OFFLINE_ROLLBACK_SEGMENTS is a unsupported init.ora parameter which can allow you to cause logical database corruption.

  _CORRUPTED_ROLLBACK_SEGMENTS is  more dangerous parameter  than _OFFLINE_ROLLBACK_SEGMENTS. It basically prevents access to the  listed rollback segments headers and assumes all transactions in them are committed.  This can very easily cause logical database corruption.

It is imperative that these parameters are not used without contacting
Oracle first.


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