Oracle Application Express

Oracle Application Express

Developer(s)	Oracle Corporation
Stable release	3.1.2 / August 28, 2008
Operating system	Linux and Windows
Type	Oracle database development environment
License	Oracle Technical Network License (Proprietary)
Website	Oracle Application Express

Oracle Application Express (Oracle Apex, previously named Oracle HTML-DB) is a free ('gratis') software development environment based on the Oracle database [1]. It allows a very fast development cycle to be achieved to create web based applications. It can be used for departmental-style applications with a dozen users, but can also scale up to handle thousands of users. The framework itself adds as little as 0.04 second of overhead to each page request; how well an application scales is primarily based on the efficiency of the SQL queries used by the application developer.

Background

Oracle Application Express can be installed in an Oracle 9.2 or higher database, and starting from Oracle 11g it will be preinstalled along with the database.

In January 2006 Oracle renamed HTML DB to "Oracle Application Express". Version 2.1 of Apex was bundled with the free Oracle Express Edition (XE) database.

In 2007 Oracle released Apex 3.0. This third major version features several new features, notably PDF Printing and Flash charting. Apex 3.0.1 was released in July 2007, and this version can also be installed into an Oracle XE database.

Historically speaking, Application Express has gone through many name changes since its inception in 2000. A reasonably complete history of the names includes:

• Flows
• Oracle Platform
• Project Marvel
• HTML DB
• Application Express (APEX)

One popular misconception is that it's a new version of Web DB. Mike Hichwa created Web DB, a successful web front-end for Oracle, but the development of Web DB started to move in a direction that diverged from Mike's vision. When tasked with building an internal web calendar, Mike enlisted the help of Joel Kallman and started "Flows". They co-developed the Web Calendar and Flows for several years, adding features to Flows as they needed them to develop the calendar. In the earliest days of Flows, there was no front-end for it, so all changes to an application were made in SQL*Plus via inserts, updates and deletes. For a while, Flows and Web DB shared a lot of code, but as the months went on, most of that code was improved or re-written. Sometime around 2002 all Web DB code was removed from Flows. So, in some ways APEX is an evolution of Web DB, but it was really a fresh start with new code and no upgrade path.

One of the most well known applications developed in Application Express is the AskTom application developed by Thomas Kyte. Oracle's Metalink support site also runs on Apex.

Pros

Fast development, 100% web based, No code required, Ready to use components, Professional looking, Easy to create mock-ups, Easy to deploy, Easy to understand, Fast (no overhead)

Cons

Database lock, Platform lock, Difficult to debug, Tricky to customize, Version control somewhat difficult (because comparing sources files for changes is cumbersome), Page-embedded Javascript and uploaded images are not cached Large installation (V3.1.2 is 532Mb)

External links

• Oracle Application Express
• Oracle Corporation
• sourceforge website for Oracle Application Express
• unOfficial Apex (Oracle Application Express) Wiki
• Blogs related to APEX

Citations

• Oracle (January 2006). "Oracle Application Express Best Practices" p.17, Oracle White Paper