Expert Oracle Application Express

I have just seen half of the chapters in this upcoming book. And I only can say: WOW! The content of this book is just so good. So this is definitely a must-have! You can pre-order it already (click here). And - again - all revenues go to charity....

Comments

John Scott said…

and you forget to add that you wrote one too ;)

John.

10:08 am

Stew said…

If only they'd ship it! I ordered it from Amazon.com back when it was first announced, but they say it won't ship until the 24th. If I had an Apex project in the works, I'd be drooling for it. Sadly, I don't have anything Apex-bound on the horizon.

But that's one of the beauties of digital books. I can get this now via Apress.com's Alpha program.

1:46 pm

Buzz Killington said…

So if all the money goes to charity, do I get a tax exemption for buying this?

4:47 pm

Roel said…

@Buzz : You can save the receipt and use it for your tax declaration ;-)

4:52 pm

Filtering in the APEX Interactive Grid

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Stop using validations for checking constraints !

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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