On Wed, Feb 3, 2010 at 10:10 PM, Rayson Ho raysonlogin@gmail.com wrote:
Seems like it is no easy way to display all the media files under a wikimedia category -- for example if someone wants a picture of a library, he or she will need to go into each sub-category under "Libraries":
http://commons.wikimedia.org/wiki/Category:Libraries
While Wikimedia is not yet the most popular stock photo source, IMO having this flattening functionality would be useful to those who are looking for stock photos.
This is a regular request. There are two major problems:
1) Our database schema is not set up to handle this efficiently for large result sets. At least I don't think so, off the top of my head.
2) In practice, collapsing categories like this can often lead to crazy stuff being included, because subcategory relations aren't used strictly in a "everything in category A is also in category B" sense. It's easy to come up with examples. For instance: [[Category:Punishments in religion]] -> [[Category:Religion and capital punishment]] -> [[Category:People executed for heresy]] -> [[Category:Joan of Arc]] -> [[English claims to the French throne]]. Thus, if you try to get all articles in [[Category:Punishments in religion]] or subcategories, you'll get results like [[English claims to the French throne]].
However, this is definitely on the long-term "it would be nice if someone did this someday" list.