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Underscore Parameters Set In Pluggable Databases Are Not Persistent After Restart (Doc ID 2335758.1)

Last updated on MARCH 18, 2022

Applies to:

Oracle Database - Enterprise Edition - Version to [Release 12.1]
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 Exadata Express Cloud 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 parameter _optimizer_use_feedback=FALSE applied on 12c PDB not persistent after restart.
Similarly, there are other underscore (Optimizer related and other) parameters that are set but not persistent after database restart.
As the parameters are not set persistently in PDBs, there are suboptimal execution plan for the SQL statements in PDBs upon database restart.


 Upgrade to 12c multitenant environment (CDB/PDB).


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