When you create a PDB, the database automatically creates and starts a service inside the CDB.The service has the same name as the PDB. It is possible that the name of the service will collide with an existing service name which is registered with the same listener. For example if two or more CDBs on the same computer system use the same listener, and the newly established PDB has the same service name as another PDB in these CDBs, then a collision occurs.
You must not attempt to operate a PDB that causes a collision with an existing service name.
Top 12 Features of Oracle 12C Summarized. This article is also available at www.ondemanddb.com
Summary: The Oracle 12C means different things to different people. It all depends on which areas you are looking at, as there are improvements in many areas. Summarized below is the list of Top 12 Features of Oracle 12C as I see it. I have summarized below, the top 12 which I found interesting.
Apps clone is like cloning a human being. Please read the detail below.
1) Run adpreclone on DB/CM/AP tiers
This is pre-requisite step of cloning 11i prod and will not change anything in any system. This script will only create on $COMMON_TOP, a directory called "clone", with a basic structure of executable, scripts, templates and java files. Later to the creation of the clone directory, the process picks up important information of your source system with which upgrades the necessary templates for the process adcfgclone that was carried out in the target server.