Application Express utilizes a Web browser on the user's computer communicating through a Web listener to the Oracle Database. No client software, other than a browser, is required for development, deployment or runtime. Application Express pages are rendered using HTML within the browser. Page requests and submissions are sent to the Application Express engine within the Oracle Database.

Oracle Application Express is an integrated feature of the Oracle database. The essence of Oracle Application Express is over 300 tables and 200 PL/SQL objects containing more then 300,000 lines of code. The Oracle Application Express engine renders pages dynamically in real time from the data contained within the Oracle Application Express metadata repository.

When you create or extend an application, Oracle Application Express creates or modifies the metadata stored in its database tables. When the application is run, the Oracle Application Express engine then reads the metadata and displays the requested page or processes page submissions.

To provide stateful behavior within an application, Oracle Application Express transparently manages session statHTTP/1.1 500 Internal Server Error Server: Oracle XML DB/Oracle Database Content-Type: text/html; charset=UTF-8 X-DB-Content-length: 24732 Transfer-Encoding: chunked Transfer-Encoding: chunked