ORA-65096: invalid common user or role name - oracle

Question

Hi I've tried to create a new user in Oracle 18c XE, but I get
ORA-65096: invalid common user or role name error when writing
create user student identified by "student";
I've tried to change the container to PDB by
SQL> alter session set container =PDB;
as I've understood that you should set that when trying to create a local user but I get the following error:
ORA-65011: Pluggable database PDB does not exist.
Do you have any idea how could I create a new user with all privileges from the command prompt?

Answer 1

A user cannot be created on a container for a DB with vers. 12c+.
So, need to alter as you did, but should display which pluggable databases are available :
SQL> select name, pdb from v$services order by pdb, name;
NAME PDB
----------------------------------------------- ----------
SYS$BACKGROUND CDB$ROOT
SYS$USERS CDB$ROOT
pdb1 PDB1
pdb2 PDB2
and check out the container by
SQL>show con_name
CON_NAME
——————————
CDB$ROOT
and check for the pluggable databases
SQL> select name,open_mode from v$pdbs;
NAME OPEN_MODE
------------------- ----------
PDB$SEED READ ONLY
PDB1 MOUNTED
PDB2 MOUNTED
change container to a pluggable database
SQL> alter session set container=pdb1;
Session altered.
and open it
SQL> alter pluggable database pdb1 open;
Now, you can apply
SQL> create user student identified by student;
as an example.

Answer 2

First run the following command:
SQL> alter session set "_ORACLE_SCRIPT"=true;
After that, create the user:
SQL> create user student identified by student;