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Don Burleson Blog 







_smu_debug_mode tips

Oracle Database Tips by Donald BurlesonMay 20, 2016

Question: What does the hidden parameter _smu_debug_mode do?  How do I use _smu_debug_mode do debug a corrupted data file?  Can you show an example of using _smu_debug_mode?

Answer:  The _smu_debug_mode is used to set other parameter values and it should only be used when working directly with Oracle technical support.

--If you find an error like this one below,
ORA-30019: Illegal rollback Segment operation in Automatic Undo mode
--then you need to follow these steps:

alter session set "_smu_debug_mode" = 4;


--Or, if you got this another error below
ORA-06510: PL/SQL: unhandled user-defined exception
ORA-06512: at "sys.dbms_transaction", line 94
ORA-06512: at line 1

--then you need to follow these steps:
rollback force '7.12.102';


alter system set "_smu_debug_mode" = 4;


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