As you're probably aware Oracle recently announced the certification of the database version #23ai with E-Business Suite for a lot of platforms (of course only where the product is available at all; so NOT on Premise and not on OCI compute yet): https://blogs.oracle.com/ebstech/post/ebs-122-now-certified-with-database-23ai-onpremises-exadata
As Elke Phelps pointed out in her blog even before, there is a couple of things you can and should do in preparation of an upgrade: https://blogs.oracle.com/ebstech/post/ebs-122-certification-with-db-23ai-and-later-oracle-database-releases
As is also mentioned in the Interoperability Notes: Oracle E-Business Suite Release 12.2 with Oracle Database 23ai (Doc ID 2962871.1) it is mandatory to convert to case-insensitive PDB name. I did this for 2 different customer scenarios in the previous weeks.
With a real lower case PDB name
For some customers that went through a 19c upgrade in a RAC environment recently the PDB name was actually lowercase. I order to overcome this and get rid of the deprecated parameter you have to follow the (quite lengthy) procedure that is described over there: Implementing Case-Insensitive Pluggable Database Names with Oracle E-Business Suite Release 12.2 on Oracle Database 19c Multitenant Architecture (Doc ID 2782130.1).
While this is a lengthy procedure it is well documented and has worked smoothly for me so far.
With an upper case pdb name
For some other customers though (that are running the database on OCI Compute) I faced a slightly different situation: Also, on those environment the parameter "_pdb_name_case_sensitive" was set to true, however the PDB name actually was in all uppercase.
In this scenario (this got also confirmed through an SR) it is not necessary to go through all the unplug/re-plug-in pain described in 2782130.1. It is enough to just do:
# Connect to the CDB: sqlplus / as sysdba alter system reset "_pdb_name_case_sensitive" scope=SPFILE; exit; # Then bounce: /u01/install/APPS/19.0.0/appsutil/scripts/PROD_prodebsora/adcdbctl.sh stop immediate /u01/install/APPS/19.0.0/appsutil/scripts/PROD_prodebsora/adcdbctl.sh start
unset parameter with upper Case
Summary
I highly recommend doing this (and other, such as the AD/TXK upgrade to release 16) before the 23ai upgrade; this reduces the impact and the downtime of the actual 23ai upgrade; and most of those steps should not have too big an impact.