In the process of setting up an Oracle 19c instance for a new install of a Gen 8.6 Windows/Oracle CSE.
Our DBAs have reviewed the file initdbcse.ora and have concerns about the "compatible ='12.1.0'" statement in it.
This is the exact comment from our DBA:
"My concern at the moment is the COMPATIBLE parameter. I am using Oracle Cloud Infrastructure (OCI) to build a 19.18.0.0 CDB and I cannot see how to set a lower value of the COMPATIBLE parameter during the OCI build."
NOTE: Prior to doing the local database install, a remote install is being done using Oracle Cloud at Customer infrastructure. It is understood that the use of a remote database for the Gen CSE is not recommended/supported and this is only being done for initial testing.
The issue around the DBA not being able to set the COMPATIBLE parameter when creating the database in OCI is therefore not directly relevant from a Gen support perspective.
However, the fundamental question is does the Gen 8.6 CSE really require "compatible ='12.1.0'" for a new Oracle 19c install?
Gen Engineering doesn't believe that any Oracle features used in the Gen 8.6 CSE have been deprecated in Oracle 19c.
The init*.ora files delivered with the CSE are actually more of a guide.
The CSE Configuration step doesn't install a database so the assumption is that the user has already created their database. So it would be up to the user if the compatible parameter needs to be changed or even removed.
In summary, if creating a new database using Oracle 19c and not upgrading from 12.1, it should not be necessary to keep the "compatible ='12.1.0'" parameter.
Gen™ 8.6 > Encyclopedia > Client Server Encyclopedia > Use the Client Server Encyclopedia > Install and Configure CSE > Prerequisites for CSE Configuration
Unless an OCI based database is different it appears Oracle 19c still supports a minimum COMPATIBLE parameter value of 11.2.0 but in 21c that was raised to 12.2.0
https://docs.oracle.com/en/database/oracle/oracle-database/19/refrn/COMPATIBLE.html
https://docs.oracle.com/en/database/oracle/oracle-database/21/refrn/COMPATIBLE.htm