Building a Kscope14 schedule ...

Building a schedule for Kscope seems to get harder and harder every year. The number of interesting sessions per time slot is usually more than 3, so it's very hard to pick one - because you're pretty sure you are missing a few other good ones. And via Twitter you'll find out pretty soon whether you picked the right one or not.
A complicating factor is the World Cup that's organized simultaneously - just like four years ago in Washington. Luckily the Dutch team is scheduled only once in that week: on Monday morning at 9AM. So that means ... I have to skip the opening ceremony.
For the rest of the week it's just packed. Some people think attending conferences is a holiday. Once you've done Kscope you know better. It's work. Hard work. And it is so much fun!
But in the end I managed to create a schedule (see below if you actually do mind). There's still a few slots with two sessions in it. So I have to split myself now and then.
I'm doing two sessions on Tuesday myself. Both on APEX Mobile. One is a beginners session, the other one is about creating native (or hybrid) applications with APEX.
Really looking forward to it. Especially meeting all the old friends and making new ones! See you in Seattle!!!

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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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