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How to get plan signature tracing for ORA-12850 (Doc ID 2180844.1)

Last updated on MARCH 12, 2021

Applies to:

Oracle Database - Enterprise Edition - Version and later
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 Database Exadata Express Cloud Service - Version N/A and later
Oracle Cloud Infrastructure - Database Service - Version N/A and later
Information in this document applies to any platform.


ORA-12850 errors are usually caused by the slave getting a plan signature different from that of the QC.  These are typically, although not always, QRY OPTIMIZER bugs.  This note provides the recommended tracing needed in order to see if there is a signature-plan mismatch and diagnose the cause of ORA-12850.   

Troubleshooting Steps

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In this Document
Troubleshooting Steps

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