Streams recreation - meta data mismatch


Sometimes the streams drop and recreate may not clean up all off relevant meta data. So far I have come across one instance  where a data mismatch caused the failure to create capture process.


This blog will be used to catalogue these errors and where possible document the fix.  


Error: ORA-00001: unique constraint (SYSTEM.LOGMNR_SESSION_UK1) violated
The error was reported on one of test systems while re-creating Capture Message queue.


The root case was down to a mismatch between DBA_CAPTURE view showing 0 rows and SYSTEM.LOGMNR_SESSIONS$ returning 1 row for the capture process.



The soution in this case was to delete the offending row from SYSTEM.LOGMNR_SESSIONS$ and re-run DROP_RECREATE_STREAMS_CAPTURE stored procedure.


Note: Some of the other options worth considering, but not used in this instance were

  • use DBMS_STREAMS_ADM.REMOVE_STREAMS_CONFIGURATION()
  • Refer How To Rebuild LogMiner Metadata Tables [ID 550197.1]. Before actioning the steps listed in the document make sure the table structure of SYSTEM.LOGMNR_SESSION$ matches with the one detailed in the article.

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