ORA-12919
Tried to drop a tablespace, but it failed with ORA-12919.
SQL> drop tablespace erptbs including contents and datafiles;
drop tablespace erptbs including contents and datafiles
*
ERROR at line 1:
ORA-12919: Can not drop the default permanent tablespace
ORA-12919 means that the tablespace you want to drop is required to be the default permanent tablespace of the database.
To solve ORA-12919, you have to change the default permanent tablespace to another one.