Track 3: Developing Multimedia Applications for the Internet
Presenter: Marcel Kratochvil
Developing web based programs can be a challenging task. Hurdles such as security, handling multimedia, scalability and flexibility need to be addressed. By using PL/SQL running on Oracle 10g, these issues can be overcome—if the database and PL/SQL features are used correctly. Working from the dual perspectives of both DBA and developer, and using experiences gained after six years of development of Piction (an internet based digital image delivery system), Marcel will use live code as a foundation to focus on the three key areas of web development: web based interfaces, multimedia and internet security.
Session 1. Web Based Interfaces
HTML is based on standards which should ensure that a web based application will perform the same regardless of the browser. However this is not the case, just like SQL different vendors modify and implement it slightly differently making it challenging to develop a cross platform application. Issues such as Javascript, Flash, Java, varying screen resolutions and different implementations of web browsers have muddied the waters, making it now quite complex to develop user friendly and intuitive applications. This session will focus on how to develop PL/SQL applications that scale to support large data volumes and large numbers of concurrent users. The session will also cover the use of style sheets, when to use Javascript, developing applications that run across multiple platforms and browsers. In addition the session will detail how to develop interfaces that can change and adapt to meet new trends and styles that appear on the Internet, quickly and with minimal programming effort.
Topics Covered:
- Why and when to use PL/SQL for web based interfaces
- Experiences of user requirements in the field.
- Developing flexible interfaces
- Dealing with different browsers, screen resolutions and network bandwidths
- Working with code that runs across multiple operating systems.
- Web Based Reporting
- CSS. Style sheets and should they be used.
- Use of HTML templates
- When to use Javascript
- Handling scalability as data volume grows and concurrency increases.
- Which version of Oracle to use and various database installation and configuration techniques.
Session 2. Multimedia and PL/SQL
Try to get two professional photographers to agree on what is a good photo is like trying to get a DBA and Developer to agree on an efficient database design. The next evolution in the Internet involves putting up multimedia onto the web site and create an image library that can be used for publishing or for selling. Multimedia includes Digital Photos, document, video and audio. As disk storage has been cheaper it is now practical to store originals inside the database simplifying their delivery. This session will focus on how to use PL/SQL to achieve this. The session will also cover the different methods available for loading and delivering that multimedia. These methods include loading and unloading via a browser, zipped file, network drive, ftp, xml and email. In addition image manipulation and metadata management using Oracle Intermedia will also be discussed and how to fast track application development using the new Oracle 10g features.
Topics Covered:
- How to store digital images in the Oracle Database (images include photos, documents, audio and video)
- Oracle's storage types and methods (covering Oracle Intermedia).
- Using ImageMagick as an extension to Oracle Intermedia.
- How to load images into the database.
- How to retrieve images from the database
- How to extract metadata from images (covering EXIF, IPTC and Adobe XML standards)
- Techniques for cataloguing and indexing indexing images
- Comparing Oracle Spatial to Oracle Intermedia
Session 3. Internet Security
It isn't enough to secure a web based application just by having a good firewall. Back doors can still be accessed through the firewall by using URL code injection and by HTML manipulation. By URL manipulation it is very easy to steal images stored in external file systems, making it very hard to sell or distribute images on the Internet. This session will cover the techniques for securing a PL/SQL web based application. It will cover known hacks and detail how to develop a secure on-line application and prevent unauthorised access or theft of digital images. Discussions on LDAP and the use of cookies will be covered as well as auditing techniques and securing the Oracle HTTP Server (Apache).
Topics Covered:
- SQL Code Injection
- URL issues
- Encryption
- Common Hacks
- Apache Security
- Which security system to use
- Auditing