Oracle multi-tenant in the real world - Working with PDBs in 12c - Mike Dietrich
https://apex.oracle.com/pls/apex/f?p=202202:2:::::P2_SUCHWORT:multi2013
alter parameter
alter system set parameter=value container=current|all; select name, value from v$system_parameter where ispdb_modifiable='TRUE' order by name;
create user
create user tim container=current|all;