I Have a question ,and I think you can help me, I'm working on database design and software engineering I need some tools for designing the models, I tried Microsoft Visio but I think it only accept charts but doesn't process them I mean it doesn’t understand them I want a tool so that it can understand an ERD entity and relationship and e.g. put its details in something like a data dictionary also I need it has facilities for designing DFD(data flow diagrams) in this way, something like Rational Rose for RUP, please help me ,thanks
You posted your question inside the Oracle Designer Headstart forum. It's is not the correct forum for your question, but I can give you the following answer.
The tool you are looking for is Oracle Designer and is part of the Oracle Developer Suite. In Oracle Designer you make ERD's and DFD's and it has a repository inside the oracle database where your entities and relationships are stored.
There is also the tool called SQL Developer Data Modeler. SQL Developer Data Modeler is a free data modeling and design tool, proving a full spectrum of data and database modeling tools and utilities, including modeling for Entity Relationship Diagrams (ERD), Relational (database design), Data Type and Multi-dimensional modeling, with forward and reverse engineering and DDL code generation. SQL Developer Data Modeler has the option to use subversion as a file based repository.