AutoUpgrade, my first incident

Did you know that AutoUpgrade fails if the server names are not in lowercase and you are working with a RAC One Node database.
Schrödinger’s Fast Recovery Area

What to do when Oracle reports an incorrect value for the space used in Fast Recovery Area.
DataGuard switchover with wallet: ORA-01017

Learn how to resolve and avoid the ORA-01017 error when you have Oracle Data Guard with wallet implemented.
Troubleshoot: enq: TX – row lock contention

Learn how to identify the row involved in the occurrence of the wait even “enq: TX – row lock contention”
Troubleshoot: CRS-2304 GPnP profile signature verification failed.

Learn how to resolve the CRS-2304 GPnP profile signature verification failed error when starting an 11.2 database on a 19c cluster.
Oracle Home permissions corrupted? Solve it in a jiffy!

Learn how to fix corrupted permissions on an Oracle Home, either Oracle Grid or Oracle Database Server.
Fighting against the clock

What to do when we find that the database returns the time advanced or delayed for no apparent reason.
Missing archivelog? Don’t rebuild your Standby (12c style)
Link to article published in Toad World, about how to overcome the lack of archivelogs to synchronize a standby database in Oracle.
Troubleshoot: losing control
The enq: CF – contention event could be resolved with controlfile maintenance if the controlfile contains a large number of archived log records.
Troubleshoot: confused optimizer
If the Oracle optimizer chooses inefficient execution plans on queries that use MAX or MIN, it is possible that this is bug 5611962.