Looking forward to UKOUG 2012

As every year, the UKOUG conference is planned in the first week of December - and therefore as always nicely clashes with a Dutch national event, called "Sinterklaas" (see http://en.wikipedia.org/wiki/Sinterklaas for the background information on that event!). Luckily my kids are somewhat older now (and "non-believers"), so we can plan our own private event in the weekend afterwards....

Nevertheless, I am really looking forward to this years event! It will be my sixth consecutive attendance (and presentation), so I know what to expect: Great content, good atmosphere, lousy weather...

As usual I used the schedule planner (which has a great integrated App now as well) to guide me through these three days.

I am really looking forward to two sessions in particular (apart from my own at Monday afternoon): "Deploying and Developing Application Express with Oracle Pluggable Databases" by David Peake and "Oracle APEX - Websockets (or When Push Comes to Shove)" by John Scott - got raving reviews when he did this at KScope12...

And of course the social events are at least as important as the sessions: Sunday night's ACE Dinner in particular (thanks to Debra Lilley for organizing!).

Comments

Filtering in the APEX Interactive Grid

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If you run your APEX application - like a Form based on the EMP table - and test if you can change the value of Department to something else then the standard values of 10, 20, 30 or 40, you'll get a nice error message like this: But it isn't really nice, is it? So what do a lot of developers do? They create a validation (just) in order to show a nicer, better worded, error message like "This is not a valid department". And what you then just did is writing code twice : Once in the database as a (foreign key) check constraint and once as a sql statement in your validation. And we all know : writing code twice is usually not a good idea - and executing the same query twice is not enhancing your performance! So how can we transform that ugly error message into something nice? By combining two APEX features: the Error Handling Function and the Text Messages! Start with copying the example of an Error Handling Function from the APEX documentation. Create this function

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