Here’s some of my favorite Oracle Database 12.2 Multitenant new features that I can talk about at this time. Oracle Database 12c Release 2 is slated to go live sometime this year.

Pluggable databases

  • The number of PDB limits per CDB increases to 4096 rom the limit of 252 PDBs in 12.2. Even though we do not have customers who have over 252 PDBs or even venture in this high number of PDBs, Oracle raised this limit in 12.2.
  • Resource manager will have the capability to limit the memory and govern CPU and I/O.  For RAC (or RAC One Node) services associated to a PDB, oracle will not have interconnect overhead
  • In 12.2, we will no longer need to to put the PDB in read-only mode to perform hot clones.  
  • We can refresh PDBs online.  
  • We can relocate PDBs without any downtime.  We can move PDBs from one CDB to another.  Larry Ellison in OOW 2015 did a live demo and moved a PDB from on-premise to Oracle Public Cloud.  12.2 eliminates the need to put the PDB in read-only mode.
  • Proxy PDBs are introduced.  We can have a new kind of a PDB which points to a remote PDB.  The remote PDB is presented as a local PDB and in all practical purposes looks like a local PDB with all functionality is available to the Proxy PDB.
  • All new Application Containers are introduced. Oracle revolutionizes the concept of having a single master application definition for all the tenant containers. We can make changes to just location and changes will sync to all the tenant container.

Are you up on Oracle new features? Are you considering pluggable databases? Let’s take a look at the new features that Oracle introduced in Even though this is not a major release of Oracle, it is still packed with new features, especially in the world on multi-tenancy. The enhancements made to pluggable databases are really attractive. Here’s a brief overview of the new features in pluggable databases:

  • FDA Support for CDBs
  • PDB Containers Clause
  • PDB File Placement in OMF
  • PDB Logging Clause
  • PDB Metadata Clone
  • PDB Remote Clone
  • PDB Snapshot Cloning Additional Platform Support
  • PDB State Management Across CDB Restart
  • PDB Subset Cloning

Every DBA should know how to leverage these commands. DBAs need to add this list of commands in their arsenal.


Additional commands for your toolkit:
free –g (Memory free in Gigabytes)
free –g –s 1 (Display free in Gigabytes, update every second)

sar -u 2 10 (Report CPU utilization for each 2 seconds. 10 lines are displayed.)