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Parallel Query Fails Intermittently With ORA-12842 Starting in RDBMS (Doc ID 751588.1)

Last updated on FEBRUARY 02, 2022

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.


Starting in, a select statement executing in parallel failed intermittently with "ORA-12842: Cursor invalidated during parallel execution."

Further investigation revealed the following:

  1. The issue did not occur in   
  2. DDL was being performed on the objects involved in the select statement at about the same time that the query was running.
  3. In this case, exchange DDL was being performed on a partition of a partitioned table.  However, the issue is not limited to only exhange operations, nor is it limited to only partitioned objects.   Cursors can be invalidated for various reasons, including the running of dbms_stats on an object.



The database was upgraded to or higher version.


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