Automatically Open PDBs When CDB started

To automatically open PDB when CDB is started, we can use trigger at CDB level.

1. Login to CDB root

SQL> show con_name

CON_NAME
------------------------------
CDB$ROOT

SQL> CREATE TRIGGER open_pdb3
  2  AFTER STARTUP ON DATABASE
  3  BEGIN
  4  EXECUTE IMMEDIATE 'ALTER PLUGGABLE DATABASE pdb3 OPEN';
  5  END open_pdb3;
  6  /

Trigger created.

2. Test it 

[oracle@ora12cn1 Desktop]$ srvctl stop database -d ora12c
[oracle@ora12cn1 Desktop]$ srvctl start database -d ora12c
[oracle@ora12cn1 Desktop]$ sqlplus / as sysdba

SQL*Plus: Release 12.1.0.1.0 Production on Tue Dec 10 17:53:27 2013

Copyright (c) 1982, 2013, Oracle.  All rights reserved.


Connected to:
Oracle Database 12c Enterprise Edition Release 12.1.0.1.0 - 64bit Production
With the Partitioning, Real Application Clusters, Automatic Storage Management, OLAP,
Advanced Analytics and Real Application Testing options

SQL> select name, open_mode from v$pdbs;

NAME                         OPEN_MODE
------------------------------ ----------
PDB$SEED                      READ ONLY
PDB2                          MOUNTED
PDB3                          READ WRITE
PDB3_CLONE                    MOUNTED