Make careful investigation before you apply PSU with CPU Jan,2012

From: Kamus <>
Date: Tue, 22 May 2012 16:07:05 +0800
Message-ID: <>

Hi lists
According to MOS document id 1393363.1, if scnhealthcheck.sql result is "C - SCN Headroom is low", then “apply the latest recommended patches right now“, this is exactly we used to suggest our customers to do, but these few days, we found there is a big risk if you apply the latest PSU without careful investigation.

In brief, if you don't apply the PSU, you will never get "ORA-19706: invalid SCN" when you select something through database link, but if you applied, it's possible to get this error and not easy to get a workaround, even with "_external_scn_rejection_threshold_hours" hidden parameters.

attachment is my test, if you have interest, have a look.


Zhang Leyi (Kamus) <>

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-- Received on Tue May 22 2012 - 03:07:05 CDT

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