A couple of day ago a had a task to combine a list with itself. The result should be a two column report of each possible combination.
What should note be part of the result:
- same element combination should be excluded
- duplicate rows (even if the sides are switched)
Because I was just not able to solve it myself *actually it's awful after I now know how to do it* I had to create a forum entry:
Oracle SQL and PL/SQL forum: Generate some kind of cartesian list
Oracle is gearing up to release APEX 5.0... the final early adopter release (EA3) will be released soon. Over 6000 people participated in APEX EA2...
In the previous post I showed some options how you can represent a many-to-many table relationship in a report using the LISTAGG Oracle function.
In this post we will edit a record and see how we can represent the data in a Form and save the data back to the different tables.
First I create a Form on the main table (customers) by just following the wizards.
Consider my case: I've a customer table and a products table. Customers can select multiple products they want to have. The diagram look like this: Customers on the left, Products on the right and a table in between that says which customers like which products. Customers might have multiple products and products might be linked to multiple customers - so a many-to-many relationship.
In the previous post I talked about scalable vector images. In this post we will integrate Font Awesome in our APEX app, but the steps for the same if you would pick another library.
Step 1: we need to make the library available in our APEX application.
The easiest way to make the library available in your entire application is to add the following line in your Page Template:
I've recently been involved with extending a number of systems that have pre-built data models. I'm generally unhappy with these data models for a variety of reasons. There are many great texts on data modeling. I will try to put together a bibliography in an upcoming post. For now, I'll start by discussing the "never delete data" trend. It is generally coupled with the use of a column to indicate that the data should have been deleted (typically a column named VOID) but was instead allowed, indeed required, to linger forever in the table.
After I described how to successfully import XML files into an APEX application and gave some basic information about the analyzing of xml data.
It's time for another example. This time we want to get all detail elements of a master element in one row.
Example XML data:
<?xml version="1.0" encoding="UTF-8" standalone="no"?>
For a couple of years now webdesigners and developers don't use image icons anymore, instead we moved to scalable vector icons.
Before you had to create different images for the different formats and colours you wanted. Then to gain performance we created one big image with all those smaller images in it (called a sprite).
Next with some CSS we showed a part of the bigger image. A hassle...
In fact the evolution of using icon images you can perfectly see in APEX too. If you go to your images folder you will see many .gif files, all different icons:
In 2015 most APEX-only conferences are scheduled in history. I definitely recommend to attend at least one of the conferences as it's a great time to meet other people, industry experts and the APEX Development Team.
You'll find me at following conferences: