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ODTUG Kaleidoscope 2008 : Day 1


Today started off with a keynote of Vince Casarez about ‘Web 2.0 meets the enterprise'. He showed some really cool stuff included in Webcenter, like the carrousel (similar to the iTunes coverflow), dynamic charts that were refreshed using push technology. This is the stuff Oracle itself is using for their Fusion apps.

Next John Scott was on for his APEX Hints, Tricks and Best Practices. They were all very useful so I'll list them all 10.

  1. Don't use the default SYSAUX tablespace for the APEX environment, but use dedicated tablespaces instead to make the installation more manageable.
  2. Create specific accounts for all developers, making QA and auditing easier.
  3. Always lock a page when you make changes and document these changes using the comment property.
  4. Use aliases for applications and pages, so f?p=SALES:HOME instead of f?p:117:17.
  5. Use the possibilities of APEX to support re-use of code, like Shared Components, Page 0, UI Defaults and Publish / Subscribe. A little explanation on the last one: If you copy an object you can define it as a subscription to its original. Modifications to the original can then be published to all subscribers.
  6. Use bind variables whenever possible. So don't code WHERE NAME = ‘%P7_SEARCH%', but use :P7_SEARCH instead. So in general:
    • Use :APP_USER in SQL or PL/SQL within APEX
    • Use &APP_USER. within HTML text
    • Use v(‘APP_USER') outside the APEX context
  7. Use database packages to code your PL/SQL.
  8. Don't use HTML markup or CSS in SQL queries: keep presentation and logic separated. Use HTML expressions and templates instead.
  9. Use the Supporting Objects for deployment. There you can define scripts that should run when your application is installed, upgraded or removed. Also use the Build Options, they're great for excluding features that are still on hand.
  10. Be pro-active: use the Application Reports, the Apex Dictionary and Pro-active Monitoring so that you will be the first to know when something is not going the way you expect it to go.

  11. After John I went to (another) Thom Kyte session on 'The Top 11 New Features of Oracle Database 11g'. The most of these features were already familiar to me as I was part of the Logica team that participated in the 11g bèta test. Half of the features were DBA-related, but the features that are most appealing to developers are:

    1. the possibility to cache more using client side caching, server result caching or PL/SQL function result caching;
    2. virtual columns using expressions, constants or deterministic functions (you even can index these columns or use them in a foreign key constraint);
    3. the SQL pivot / unpivot command, so there's no need for the usual max(decode....) ‘trick'.

    In the afternoon Karen en Jan from iAdvise did a presentation on their QA-tool on APEX using the dictionary views. This is a good concept for controlling the quality of your applications on coding style and naming conventions and can be compared with the Headstart quality checks for Designer. They encountered one major technical issue: the battery of the laptop died halfway the presentation, so somebody had to pick up another power adapter.

    David Peake ended the day with an APEX 3.1 overview. To me the interesting part were the last 5 minutes (of his half an hour overdue presentation) where he showed very little of the pre-alfa version of the Oracle Forms Application Migration. With this utility you can read the XML file of a Forms module into Forms Objects in APEX. Then you can change these objects and generate an application. David didn't show the generation part (probably because it didn't work yet) and told that there was ‘some' more work to do, but the APEX team would like to deliver this feature asap... You can expect a whitepaper on OTN about his very soon!
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