I'm not sure I understand what you're asking, but the hierarchy is based on the relation between a category and its subcategories. In more technical terms, in the directed graph of categories, edges are from a category to its subcategories. Actually, there seem to be 1M+ categories (though not all of them are normal article categories). And category-subcategory links is exactly what the categorylinks dump contains, along with category-page links. Petr Onderka [[en:User:Svick]]

Thank you Mark, I was indeed looking for the tables to construct that structure. You also confirm categorylinks and categorypages are enough? On Thu, May 30, 2013 at 10:49 AM, Luigi Assom <luigi.assom(a)gmail.com> wrote: -- Luigi Assom Skype contact: oggigigi

Thank you Yury, I am looking for something like that but for all categories for analysis. I think I will use the db of wiki. On Thu, May 30, 2013 at 5:51 PM, Yury Katkov <katkov.juriy(a)gmail.com> wrote: -- Luigi Assom Skype contact: oggigigi

Hi again guys! I am still digging into wiki categories. As Brad said, there is not an hierarchy. I basically extracted categories from categorilinks.sql I have questions about the results I obtained, which is in the form #id_source_category title_target_category Problem I have is that the directed graph is actually "mixed": sometimes you have a real sub-category pointing to a parent, sometimes viceversa so I can't understand the importance - is there (maybe in another dump) a mark or parameter (smtg like "ns" maybe ? ) telling you which directory is head respect to another? As example, take "http://en.wikipedia.org/wiki/Category:World_War_II" It is written "this is root category...." - the other question is about results: http://en.wikipedia.org/wiki/Category:World_War_II collects for sub-categories which I have not found in categorilinks.sql e.g. for WWII I otain the conflicts but not other ones. Am I missing smthing ? On Thu, May 30, 2013 at 7:49 PM, Pavan Kapanipathi <pavan(a)knoesis.org> wrote: -- Luigi Assom Skype contact: oggigigi

Hello Petr, Thank you. I want to obtain this result: a list of categories such as: parent category -> subcategory Indeed I followed this structure, selecting only category pages and I obtained e.g. 690070 (sub category "Futurama", cl_from) to parent category "Comic_science_fiction" e.g. 690451 (sub category "World War II", cl_from) to parent category "Conflicts_in_1939" so I my perception is the first example is correct, instead World War II should be parent of Conflicts_in_1939 Am I right or am I missing / misunderstood something? That's correct for Modern Europe but if you compare with the page http://en.wikipedia.org/wiki/Category:World_War_II you see some links are missing in the sql dump, such as: http://en.wikipedia.org/wiki/Category:Military_deception_during_World_War_II or http://en.wikipedia.org/wiki/Category:Sociology_of_World_War_II This is the list I obtain: the above sub categories are not present: 690451 1930s_conflicts 690451 1940s_conflicts 690451 20th-century_conflicts 690451 Categories_requiring_diffusion 690451 Conflicts_in_1939 690451 Conflicts_in_1940 690451 Conflicts_in_1941 690451 Conflicts_in_1942 690451 Conflicts_in_1943 690451 Conflicts_in_1944 690451 Conflicts_in_1945 690451 Global_conflicts 690451 Modern_Europe 690451 Wars_involving_Albania 690451 Wars_involving_Argentina 690451 Wars_involving_Australia 690451 Wars_involving_Austria 690451 Wars_involving_ .... [etc.]

Ok Petr, thank you for clarification. I will also look for page_namespace = 14 and cl_to P.s. one more question: on enwiki-20130503-pages-articles-multistream-index there are some entries reporting titles with no spaces, such as: 549:10:AccessibleComputing Why are they not reported as Accessible_Computing, making it consistent with other dump files (e.g. enwiki-20130503-all-titles-in-ns0) ? Is there a special meaning for stripping the blank space? On Thu, Jun 6, 2013 at 4:13 PM, Petr Onderka <gsvick(a)gmail.com> wrote: -- Luigi Assom Skype contact: oggigigi

oh thank you!! very useful indeed! On Thu, Jun 6, 2013 at 10:55 PM, Mark Wagner <carnildo(a)gmail.com> wrote: -- Luigi Assom Skype contact: oggigigi

On 30/05/13 11:05, Luigi Assom wrote: You only need the tables categorylinks and page [entries with page_namespace = 14 (aka. NS_CATEGORY) ]