ORA-65096: create 12c user without c## prefix

Question:  I am trying to create a user in Oracle 12c and I don't give a rat's butt about pluggable databases.  When I try to create a user with the c## prefix I get the dreaded ORA-65096 error:

create user fred identified by flintstone;
ORA-65096: invalid common user or role name

I don't care if the user ID is used as a pluggable database, I just want to create a user named fred without being required to add the c## prefix (create user c##fred).

How do I fix the ORA-65096 error and create my use without a container database c## prefix?

Answer:  First, read my notes on common vs. local_user ID's. The oerr utility is not at all helpful for the ORA-65096 error:

ORA-65096: invalid common user or role name

Cause: An attempt was made to create a common user or role with a name that was not valid for common users or roles. In addition to the usual rules for user and role names, common user and role names must start with C## or c## and consist only of ASCII characters.

Action: Specify a valid common user or role name.

The solution to the ORA-06596 is to set a hidden parameter "_oracle_script".  When you set the undocumented (hidden) parameter "_oracle_script"=true  you can create the fred user without a C## in from of the user ID.  However, this user will not used useful in a pluggable/container database:

connect system/manager as sysdba

alter session set "_ORACLE_SCRIPT"=true;

create user fred identified by flintstone;

grant dba to pubs;

connect fred/flintstone

Always consult Oracle support before using any hidden Oracle parameters. Oracle makes a distinction in multitenant databases for local vs. "common" user ID's:

• COMMON USERS:  Common user ID's must always be created at the CDB level and start with a C## or c## prefixes.
  
  
•  LOCAL USERS:  Local users can only be created at the PDB layer; also must use the CONTAINER clause set to CURRENT for the user to be created.