Max PDBs in Standard Edition

Here is a small warning. In Standard Edition, you may expect that the features that are not available for your edition are blocked, but in 12.2 you can create more than one PDB in Standard Edition, and you should set MAX_PDBS to prevent that.

12cR1

In 12.1 Standard Edition, when you try to create more than one PDB (i.e with CON>ID > 3) you get an error:

ORA-65010: maximum number of pluggable databases created

12cR2

But it seems that this has been lost in 12.2:

oracle@SE122 ~$ sqlplus / as sysdba

SQL*Plus: Release 12.2.0.1.0 Production on Thu Oct 10 11:41:56 2017

Copyright (c) 1982, 2016, Oracle.  All rights reserved.


Connected to:
Oracle Database 12c Standard Edition Release 12.2.0.1.0 - 64bit Production

SQL> show pdbs

    CON_ID CON_NAME                       OPEN MODE  RESTRICTED
---------- ------------------------------ ---------- ----------
         2 PDB$SEED                       READ ONLY  NO
         3 PDB1                           READ WRITE NO

SQL> create pluggable database PDB2 admin user admin identified by me;

Pluggable database created.

SQL> show pdbs

    CON_ID CON_NAME                       OPEN MODE  RESTRICTED
---------- ------------------------------ ---------- ----------
         2 PDB$SEED                       READ ONLY  NO
         3 PDB1                           READ WRITE NO
         4 PDB2                           MOUNTED
SQL> alter pluggable database PDB2 open;

Pluggable database altered.

So, if you are in Standard Edition, don’t forget to set MAX_PDBS to 1:

SQL> alter pluggable database PDB2 close immediate;

Pluggable database altered.

SQL> drop pluggable database PDB2 including datafiles;

Pluggable database dropped.

SQL> alter system set max_pdbs=1;

System altered.

SQL> show pdbs

    CON_ID CON_NAME                       OPEN MODE  RESTRICTED
---------- ------------------------------ ---------- ----------
         2 PDB$SEED                       READ ONLY  NO
         3 PDB1                           READ WRITE NO

12:18:28 SQL> create pluggable database PDB2 admin user pdbadmin identified by oracle;
create pluggable database PDB2 admin user pdbadmin identified by oracle
*
ERROR at line 1:
ORA-65010: maximum number of pluggable databases created