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Things to Consider Before Upgrading to Avoid Poor Performance, Wrong Results or SQL Plan Management (SPM) Issues (11.2.0.X and above) (Doc ID 1904820.1)

Last updated on JULY 15, 2022

Applies to:

Oracle Database - Personal Edition - Version to [Release 11.2 to 12.1]
Oracle Database - Enterprise Edition - Version to [Release 11.2 to 12.1]
Oracle Database - Standard Edition - Version to [Release 11.2 to 12.1]
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
Information in this document applies to any platform.


The purpose of this note is to publish some recommended fixes in hopes of avoiding problems associated with performance and wrong results .

Best Practices

Pro-Active Problem Avoidance and Diagnostic Collection

Although some problems may be unforeseen, in many cases problems may be avoidable if signs are detected early enough. Additionally, if an issue does occur, it is no use collecting information about that issue after the event. For information proactive preparations and diagnostics, see following notes:

<Document 1482811.1> Best Practices: Proactively Avoiding Database and Query Performance Issues
<Document 1477599.1> Best Practices Around Data Collection For Performance Issues


This note concerns itself with highly desirable patches that are not included in PSU updates, either because they contain optimizer layer fixes or because the PSU that will contain them has not yet been released.
If you do not find a patch for your specific version and OS, please open a Service Request with details on the patch needed. Please include a list of patches already applied (opatch lsinventory -detail) as well as any other patches you intend to apply.


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In this Document
 Pro-Active Problem Avoidance and Diagnostic Collection

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