Oracle 12c has introduced CDB/ PDB architecture . Prior to 12c , Only one database can be serviced by an instance ( in a Single Instance ) / by instances ( in RAC) . In other words , no more than one databases can be serviced by an instance(s).
In Oracle 12c, we can have ( pluggable) databases that are contained with in a (container) database. Container database will not have user data , where as the pluggable database will have the user data. This is almost synonymous with Sybase / MS SQL Server or DB2. Loosely speaking , we can equate Container database as to Combination of System (master , msdb , model and resource ) databases in Sybase / MS-SQL Server.
Note : With the standard license , we can one CDB and one PDB . We would need additional license , if we are planning to have more than one PDB.
Let us say , we created a database with DBCA and asked for 2 PDBs with the pdb_docs, then we will have a CDB ( whatever we have given ) , PDB seed and two pdbs with pdb_docs1 and pdb_docs2.
As you can see , OXYZ12DB is a the containter database .
C:\>sqlplus / as sysdba
SQL*Plus: Release 12.1.0.1.0 Production on Fri May 22 13:37:02 2015
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, Oracle Label Security, OLAP, Advanced Analytics
and Real Application Testing options
SQL> select name , CDB from v$database;
NAME CDB
--------- ---
OXYZ12DB YES
SQL> select name , open_mode , restricted from v$pdbs;
NAME OPEN_MODE RES
------------------------------ ---------- ---
PDB$SEED READ ONLY NO
PDB_DOCS1 READ WRITE YES
PDB_DOCS2 READ WRITE NO
Now , let us see how we can change the name of pdb_docs2 to pdb_noncredit .
We need to be connected the correct PDB and it needs to be in restricted mode.
C:\>sqlplus sys@pdb_docs2 as sysdba
SQL*Plus: Release 12.1.0.1.0 Production on Fri May 22 13:50:16 2015
Copyright (c) 1982, 2013, Oracle. All rights reserved.
Enter password:
Connected to:
Oracle Database 12c Enterprise Edition Release 12.1.0.1.0 - 64bit Production
With the Partitioning, Oracle Label Security, OLAP, Advanced Analytics
and Real Application Testing options
NAME OPEN_MODE
------------------------------ ----------
PDB_DOCS2 READ WRITE
We need to open the PDB in restricted mode , so we can its change its name.
SQL> alter pluggable database pdb_docs2 close immediate;
Pluggable database altered.
SQL> alter pluggable database pdb_docs2 open restricted;
Pluggable database altered.
SQL> select name , open_mode , restricted from v$pdbs;
NAME OPEN_MODE RES
------------------------------ ---------- ---
PDB_DOCS2 READ WRITE YES
SQL> alter pluggable database pdb_docs2 rename global_name to pdb_noncredit;
Pluggable database altered.
SQL> select name , open_mode , restricted from v$pdbs;
NAME OPEN_MODE RES
------------------------------ ---------- ---
PDB_NONCREDIT READ WRITE YES
Here we go. Now the PDB's name is changed to PDB_NONCREDIT.
Make sure that you change your tnsnames.ora to reflect the new name .
Comments welcome.
