Posts tagged hierarchy
The recent JDeveloper/ADF 11gR1 Patch Set 6 release introduced the Sunburst component, one of the many data visualization components in ADF. Sunburst (sometimes called Rings Chart) provides an attractive and useful way to quickly learn about the hierarchical build of certain values. One well known example is the space usage on a storage device, such as on the Gnome desktop on Linux – see on the right.
The left side of the figure shows the directories on the file system and their relative and absolute size. The rings chart or sunburst makes it abundantly clear which directories contain the most data and which subdirectories inside are the big ones.
The ADF DVT Sunburst component allows us to create a similar representation of the build up of a values from their constituents and their constituents. A simple and not very exciting example is presented in this article: the salary distribution in table EMP – per department (level 1) and per employee (level 2). We will also compare this presentation as sunburst with the counterpart presentation using Treemap. The two are quite similar and can be used in similar circumstances, depending on whether the focus of using the data visualization More >
The tree map component is one of those data visualization components that can tell an entire story through a simple picture. But of course that picture is anything but simple. And it is not even just a picture: it supports various forms of interaction such as drill down and popup. I had seen the Tree Map for the first time in demonstrations by Oracle Product Management. It seemed okay, but nothing very spectacular. Now, after having tried out the component for myself as well as studying the documentation, I may have to revise my initial opinion: it is actually a pretty cool and powerful component.
The Tree Map is used to present data values in a way that makes comparison easy, using two dimensions: (relative) size and color. The TreeMap uses containers for nodes with sizes relative to the numerical value associated with the nodes. Each node can have details and the container is presented with enclosed areas for each of the details. The size of these areas is proportional again to the value associated with the child node. All areas can be colored automatically – to create a pretty picture – or can be colored according to rules we can specify in order to have the colors also convey More >
Oracle 11gR2 – alternative for CONNECT_BY_ISLEAF function for Recursive Subquery Factoring (dedicated to Anton)
On our blog, we have been discussing the new hierarchical query functionality in Oracle Database 11g Release 2, using Recursive Suquery Factoring. Instead of using CONNECT BY and its close associates such as START WITH, PRIOR, LEVEL and more exotic comrades like SYS_CONNECT_BY_PATH, CONNECT_BY_ROOT and NOCYCLE this release gave us a new, less proprietary and eventually probably more intuitive and functionally rich approach. We have also written how though we have no straightforward alternatives for LEVEL, SYS_CONNECT_BY_PATH and CONNECT_BY_ROOT – in the new recursive approach they are fantastically easy to emulate.
Until recently I have been quite happy with the new hierarchical querying and telling the world how I felt. Then an esteemed colleague – a far more experienced SQL programmer than I am – came up to me and remined me how the recursive sub query syntax at the present does not have a replacement for the CONNECT_BY_ISLEAF function – the SQL function that tells us whether a node produced in an hierarchical query has any children or is at the bottom of the chain – i.e. a leaf node. For leaf nodes (child-less), the function returns a value of one and for parent nodes the More >
One of the data visualization tags required by the teams working on the Oracle Fusion Application Module for Human Resource Management, was a component capable of rendering organization charts. Hierarchical structures from CEO all the way down to the youngest trainee. In a pleasing, graphically interesting, somewhat animated fashion. And so the ADF team developed the Hierarchy Viewer. And since they developed it anyway, we can now make use of it as well. While it may not be the component you will most frequently use, it is certainly an interesting presentation option for special data structures. This component can work against the same tree data binding you would use for tree tables or trees, and can therefore be configured in a very simple, declarative fashion.
In this article some simple examples of how to use this new component. This article is the short summary of a presentation and demonstration I did at the recent ODTUG Kaleidoscope 2009 conference (late June, Monterey). It demonstrates how the conference’s session schedule can be represented in the Hierarchy Viewer.
Presenting information to end users can be somewhat challenging, especially if you want to provide a lot of information on a single page in a structured way. You can swamp the users with information and data, claim all they need to know is there and be on your merry way (that is the way most Excel sheets look to me). On the other hand, creating the perfect Dashboard can be a very time consuming task. In this article I try to describe a simple, structured and rather effective way of presenting a lot of information – I did not devise this presentation, that’s from one of my current customers – that can be implemented fairly rapidly. Perhaps it can provide some inspiration.