Impact of "_oracle_script"=true in Oracle database 18c I just installed Oracle XE 18c (I migrated from 11g XE) ... After running the installer, I saw new features; for example, Oracle now supports a multitenat model and a concept called pluggable databases ...

The first problem that I found was creating a new user ... it appears that in order to support the concept of pluggable databases, user names must comply with some naming rule prefixes (i.e. c##) ... Searching about the problem, I found this link  ... They suggest that to create a user using the old syntax (the one used on non-CDB), we should alter the session using:

alter session set "_ORACLE_SCRIPT"=true;


But, they warn that the user cannot be used in any pluggable database ...

So, this is my question: If a create the user after submitting the command, is the user created in the ROOT Container (CDB$ROOT)? Such user will be local to the Oracle instance and can be used to administrate all other pluggable databases, including the CDB (assuming that such user has all required permissions)?

Thanks!

Disclaimer: I'm not a DBA, I'm just a software developer with advance knowledge about databases ...
Yes, common users, those starting with C##, will be created in the CDB.  They will available in all PDBs (assuming they have the correct permissions).

If you need to create a user in the PDB, make sure you connect to the PDB ( SID=XEPDB ) not the CDB (SID=XE )