Oracle Database layer and middleware layer

Oracle Database layer and middleware layer:
The underlying database is 10 Gb, while IAS and the above suites are both part of the middleware. They can be used for simple programming development with their own tools (as if they were generally developed by J2EE, the application layer has nothing to talk about, and the display layer above, that is, the unified portal system. The Oracle solution is called portal, and the built-in development and customization portal tool is called Oracle jdeveloper, is based on J2EE. similar to Microsoft CRM.. net ";