How to create Table Spaces in PDB$SEED

How to create Table Spaces in PDB$SEED 

SQL> alter session set "_oracle_script"=TRUE;

Session altered.

SQL> alter pluggable database pdb$seed OPEN READ WRITE;
alter pluggable database pdb$seed OPEN READ WRITE
*
ERROR at line 1:
ORA-65019: pluggable database PDB$SEED already open


SQL> alter pluggable database pdb$seed close immediate instances=all;

Pluggable database altered.

SQL> select open_mode from v$database;

OPEN_MODE
--------------------
MOUNTED

SQL>  alter pluggable database pdb$seed OPEN READ WRITE;

Pluggable database altered.

SQL> show con_name;

CON_NAME
------------------------------
PDB$SEED
SQL> select open_mode from v$database;

OPEN_MODE
--------------------
READ WRITE

SQL> create tablespace APEXFILE datafile '/apps/apexora/app/apexora/oradata/APEXORA/pdbseed/APEXFILE.dbf'
  2  size                                  100M
  3  autoextend on maxsize                2000M
  4  extent management local uniform size  64K;

Tablespace created.

SQL> create tablespace APEXUSER datafile '/apps/apexora/app/apexora/oradata/APEXORA/pdbseed/APEXUSER.dbf'
  2  size                                  100M
  3  autoextend on maxsize                2000M
  4  extent management local uniform size  64K;

Tablespace created.

SQL> reate tablespace APEXEBS datafile '/apps/apexora/app/apexora/oradata/APEXORA/pdbseed/APEXEBS.dbf'
SP2-0734: unknown command beginning "reate tabl..." - rest of line ignored.
SQL> create tablespace APEXEBS datafile '/apps/apexora/app/apexora/oradata/APEXORA/pdbseed/APEXEBS.dbf'
  2  size                                  100M
  3  autoextend on maxsize                2000M
  4  extent management local uniform size  64K;

Tablespace created.

SQL> alter system set db_securefile=NEVER  scope=both;

System altered.

SQL> commit;

Commit complete.

SQL> alter pluggable database pdb$seed close immediate instances=all;

Pluggable database altered.

SQL> alter pluggable database pdb$seed OPEN READ ONLY;

Pluggable database altered.

SQL> how con_name;
SP2-0734: unknown command beginning "how con_na..." - rest of line ignored.
SQL> show con_name;

CON_NAME
------------------------------
PDB$SEED
SQL>  select open_mode from v$database;

OPEN_MODE
--------------------
READ ONLY

SQL> alter session set "_oracle_script"=FALSE;

Session altered.

SQL> commit;

Commit complete.

Thanks
Srini