Oracle 12c is just upgraded version of the Oracle 11g with some new features like cloud support and pluggable database, kind of like master slave architecture. With the Oracle 12 c, you can plug your database to cloud anytime. It has multiple new features like JSON support, multitenant architecture and etc.
|Sr. No.||Key||Oracle 11g||Oracle 12c|
|1||Basic||It was released in released in 2008 and has no pluggable database||It is High performance RDbMS which is released in 2014. It is pluggable database.|
|2||Identity column||We can't set primary key to raise automatically||We can set primary key to rise automatically.|
|3||JSON type||We can't store Json directly to the column as Oracle 11g doesn't have JSON column type.||Oracle has introduced JSON column type.|
|4.||Cloud support||Oracle 11g doesn't have cloud services||It provides Oracle cloud services.|
|5.||In-memory capabilities||No in-memory capabilities||It has in-memory capabilities.|