I have been using Views 2 module a lot lately and the more I use it, the more I appreciate its elegantly designed architecture. It is very powerful and flexible. Popular modules such as Organic Groups and Location make the Views 2 module even more powerful. Showing information to end-users becomes easier when you want to show certain group posts or perhaps display the list of members of a group given a certain location.
I believe that the biggest factor which contributed to the popularity of Views 2 is its flexibility. You can pretty much override everything, from overriding its query using hook_views_query_alter(...), to being able to override its output at a very granular level(field result level).
Let's say that you want to show a yearly sales report of your 5 departments highlighting the sales per month. You can assume that a “department” is implemented as a node. Your have created a “Page” display of your View. The style of your View is set to “Table”. You have selected “Node:Title” as your department's name.
Here I will show you step by step process on how to override the result of a Views query.
1. Click “Theme:Information” under you Views “Basic settings”.