Redaction, also known as Data Masking, introduced in Oracle Database 12c is enhanced in this release. Masking templates can be defined and applied to columns with sensitive data. Support for Redaction policy at table and column level. Full support for Transparent Sensitive Data Protection (TSDP) policies that can be associated with sensitive types, domains, columns and attributes.
The Physical Model for Oracle Database 12c now includes support for IDENTITY Columns and the option to generate DDL for an auto-increment column. Increased size limit for VARCHAR2, NVARCHAR2 and RAW data types. Redaction and TSDP policy definitions can be included in generated DDL.
Building on the capabilities to search and generate reports for a design, you now have the ability to add a negation clause to a search expression and search for an empty value. Enhancements to Standard Reports allowing for created diagrams to be reused in the next report and SQL scripts to grant Read Only access to the Reporting Repository.
A complete list of 4.0 New Features can be found here.