Skype always irritated me with its automatic microphone volume changes. The Windows version has the ability to disable this option in the preferences pane, but the Mac version does not. Today, I spent some time trying to solve this problem. After some searching on net, I found a solution for the Windows version which also works on the Mac.
Whether you want to build your own forum, publish the messages from a mailing list on your Website, or write your own cms: there will be a moment that you'll want to store hierarchical data in a database. And, unless you're using a XML-like database, tables aren't hierarchical; they're just a flat list. You'll have to find a way to translate the hierarchy in a flat file.
Storing trees is a common problem, with multiple solutions. There are two major approaches: the adjacency list model, and the modified preorder tree traversal algorithm.
In this article, we'll explore these two methods of saving hierarchical data.
