Re: 12c to 19c upgrade

Posted by ErmanArslansOracleBlog on Jan 17, 2023; 10:50am
URL: http://erman-arslan-s-oracle-forum.124.s1.nabble.com/12c-to-19c-upgrade-tp11462p11464.html

1) Most user data resides in the PDBs. The root contains no user data or minimal user data. The disk storage space requirement for a CDB is the space required for the Oracle Database installation plus the sum of the space requirements for all PDBs that will be part of the CDB.
2) In general you should not. It is not a best practice. Risky In general you must not overwrite any of the datafiles residing there. At least they should not be in the same directory.