Sunday , June 16 2024

ORA-12805: parallel query server died unexpectedly error in 12c databases

In 12c databases, ORA-12805, ORA-07445 [qertqistart] or ORA-600 [15803] errors may occur depending on bug 25694206. User operation cannot be completed due to the closing of parallel processes.

The problem is corrected in version, and the following workraound can be applied to the problem.

To resolve the problem, the parameter “_px_wif_extend_distribution_keys” must be set to false.


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  1. This solved an issue we were having on a RAC instance on an Oracle Data Appliance…
    Much appreciated.

  2. Thank you.

  3. This solution definitely resolved the issue. But I wanted to know as how this parameter is affecting the programs throwing ORA-12805. We were getting this error only from OEM and no error witnessed in alertlog file of the target database nor the em database. Only seen below events in em UI
    Wait Events reported at times are
    1. resmgr:cpu quantum. (Schedular waits 47.6 %)
    2. enq: TX – row lock contention. (causing application waits ~ 33%)

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