Help talk:Category

Please note that this is not the place to ask help. If you need assistance please post you message in the Help Forum where your are welcome. This page is used to discuss what to write in Help:Category voice.

Removal

Some content has been removed, see also http://meta.wikimedia.org/w/index.php?title=Help:Category&oldid=331833

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I want to make any namespace behave like a category

The Category: namespace just sucks. I have a category Category:Music in my wiki. The URL is example.com/wiki/Category:Music. Inside there are categories Category:Artists and Category:Albums. Deeper, Category:John_Lennon in ...:Artists and Category:Lennon_Legend in ...:Albums. And if someone comes to my wiki and looks for Lennon, he/she sees this ugly word, Category:. And if a member wants to assign a song to the artis and album categories, he/she has to use this ugly word while typing [[Category:Lennon]] [[Category:Lennon_Legend]].

Yeah, I can make Category: aliases, like Artist: or Album: but it doesn't change a lot for the URL's and page names that a firs-time-using-mediawiki user sees.

So how it should be in my opinion?

Any namespace should have the ability to be a category. For example this could be modifiable in LocalSettings.php with a variable like $namespacesThatAreCategories = (101, 103, 105, ...). While assigning pages it would be very pretty for the user: [[Artist:John Lennon]] [[Album:Lennon Legend]]. So, the category three would be:

like this	and not like this
Category:Music Category:Artists Artist:John_Lennon Artist:... Category:Albums Album:Lennon_Legend Album:...	Category:Music Category:Artists Category:John_Lennon Category:... Category:Albums Category:Lennon_Legend Category:...

Anyone has an idea how to do this? An extension, a hack, anything?

PS: Sorry for my english ;-)

Do Categories help with performance?

Currently for our fairly new MediaWiki install, to which we've added maybe 100 pages we have currently not yet added any categories (yes Ive been reading up on categories this morning).

Our wiki has slowed down more recently and we're trying to get the the root of the issue. (yes we've run through the performance area in the Help:Contents documention and worked on the caching, PHP settings etc)

Is it correct that by currently having no categories allocated, that we aren't enabling wiki to effectivley index as essentially all the pages are linked just to the main page and are essentially just under one universal category, hence slowing down access times?

Or is this all bollocks and having no categories has no effect on indexing for performance?

Subcategories

How do subcategories work? Lupin 12:22, 30 May 2004 (UTC)

If you've RTFMed, please ask a more specific question!

The FM is unstructured and not to readeabel. You wiki-guys spend to much time praising your o-so-glorious work that you have stopped questening it. See this discussion page. Do actually discuss the help pages' content, or how it is presented/structured? Or do you discuss how can do even better?

I also found the section on subcategories hard to understand. Luckily I stumbled accross the Demo while searching for something else.

Before I edited the section, I briefly searched for policies on editing, but didn't really find one. There appears to be no community portal. I did find the Wikipedia motto: be bold in editing. If there is a page for new users, please post it to my talk page. Hanne 11:39, 24 December 2005 (UTC)

Redundancy of super-categories

Should we include articles in both subcats and their parent cats? I think by adding say Albert Einstein to the subcat Theoretical physicists, which is a member of the cat People, the software should automatically add Al to People. Al will also be in the Mathematicians subcat, which is a subcat of People, but shouldn't be put in People twice. One problem with not putting him in People is that these cats wont be strictly hierarchial, and removing say Theoretical physicists from People can cause Al to not be a person anymore. -- Jeandré, 2004-05-30t17:52z

No, we should not

include articles in both subcats and their parent cats

In that discussion, i suggest not using the term "hierarchical": a hierarchy involves a "graded or ranked" series, which is to say that you can count how many levels apart two things are, independent of the path you follow between them. That property belongs to graph-theory trees, where everthing (except for the root -- the "Adam" or "Eve" item) has exactly one parent. Where there can be multiple parents, as there explicitly can be here, the number of levels difference depends on which path you connect them with.

Rather than a tree, the structure we are using contemplates a DAG, and as far as i can see so far, what you are proposing is a specific sort of incest prohibition:

• an article may trace descent by two different paths from a single ancestor, but
• it cannot be a child of both a given ancestor category, and also of an ancestor of that given ancestor.

You don't say why this should be avoided, but i agree & will say it:

• the larger category is redundant (since the smaller category implies being indirectly in the larger), and
• the larger category is crowded unnecessarily by the redundant assignment. (If the tens or hundreds of thousands of people in WP are all in [[Category:People]], all of the dozens or hundreds of subcategories of people will be hidden undetectably among them.)

BTW, only removing both Theoretical physicists and Mathematicians would cause that problem re Einstein.

Now, why would either be taken out of [[Category:People]]? It should happen only if there is a larger category, also belonging to [[Category:People]], that they were being moved to instead: for instance, [[Category:Scientists]]. IMO, this objection does not weigh in favor of the redundancy. Rather, it is like a move that may produce "a drastic and unexpected change for a popular page". The objection should be raised not against forgeoing the redudant category, but against taking a subcategory out of its parent category, without ensuring (first!) that every category or article (directly) in the removed subcategory then gets into that same parent category by via another category.

--Jerzy 02:28, 6 Jul 2004 (UTC)

A clean example of this principle is the fact that there are no articles in [[Category:Countries]]. All the country articles are members of subcategories of it. --Jerzy 01:57, 14 Jul 2004 (UTC)

Subcategory article count

It would be useful to be able to have the number of articles and subcategories in parenthesis behind the subcategories in a Category: page.

List of Categories

Special:Categories doesn't seem to be working properly. How DO I see a list of the categories currently in use? --212.235.43.141 09:08, 31 May 2004 (UTC)

(Working OK now on both en: and m:. --Jerzy 02:28, 6 Jul 2004 (UTC))

could we also list by depth or volume?

The current list of categories does not seem to be ordered sensibly. An alphabetic sot makes sense, but it also makes sense to have a "volume-first" sort as well. Then, a category with a tree of 5000 categories (eg "category: people") underneath it will sort before "category: aardvarks". RayKiddy 07:44, 4 Jun 2004 (UTC)

changing category sort direction

It would be a great feature for the category sorting direction (attribute) to be controllable by a flag in the category's page. I have modified the code to fit my needs, but it's not an ideal solution.

/* Edited file : /wiki/includes/Parser.php */

Origonal : <code>$sql = "SELECT DISTINCT cur_title,cur_namespace,cl_sortkey FROM
cur,categorylinks WHERE cl_to='$t' AND cl_from=cur_id ORDER BY
cl_sortkey" ; </code>

Modified : <code>$sql = "SELECT DISTINCT cur_title,cur_namespace,cl_sortkey FROM
cur,categorylinks WHERE cl_to='$t' AND cl_from=cur_id ORDER BY
cl_sortkey DESC" ; </code>

I simply created a conditional statement based on a particular key being in the URL.. if that key is present, it reverses the sort order. This is a fairly poor solution, and could easily be improved by someone who knew what they were doing. Likewise, RayKiddy's suggestion of using "volume" as a sort key is a great idea... it too should be available in ascending and descending order. --Zeroasterisk 07:22, 16 Jan 2005 (UTC)

roadmap

is there any roadmap for the category feature? what is planned to implement to category pages? I'm thinking of:

• other sorting
• filtering
• search for categories with more/less than X articles
• listing the structure

--WikiWichtel 18:48, 13 Jun 2004 (UTC)

sorting glitches

Looks like there are still some problems to be sorted out in the sorting mechanism. Capitals and lower-case letters seem to sort separately from each other right now (see "de Man" in w:Category:Literary critics for instance) and accented characters possibly also muck up the works? And why are there sometimes multiple letter-headings for the same letter (again, "B" in w:Category:Literary critics)? -- w:User:Rbellin

The upper/lower case thing can at least be worked around by adjusting the sort keys. I don't know if there will be long term consequences to that or not. (Will sort keys ever be made visible? If not, then no consequences.) Anyway, I patched up your example above. Any other cases could be similarly worked around. I don't know if it is good policy or not. --Ssd 11:33, 18 Jun 2004 (UTC)

Thanks for "fixing" the example, but all that did was make it no longer serve as an example. The sort facility is really brittle right now; aside from the lowercase problem (which really should be fixed -- e.g., there are a zillion "de" and "von" names that should sort correctly with D and V) there is also a space problem: type a space after the pipe character, like [[Category:foo| Bar]], and your entry sorts under "space." Did some programmer confuse "ASCII sort" with "alphabetize"? -- w:User:Rbellin

I agree a case folded sort would be better. Submit it on source forge and/or MediaWiki 1.3 comments and bug reports if someone else didn't already. --Ssd 13:07, 19 Jun 2004 (UTC)

Category Redirection

I'm trying to determine a good method for category redirection, and yet I cannot find a good method. Perhaps the current SOP is to remove duplicate categories, but why not redirect Category:Businessmen to Category:Businesspeople, for instance? (The actual problem has arisen at wikiquote, but the problem must arise at wikipedia more often...

I've tried:

• #REDIRECT [[Category:Businesspeople]]
  • This, however, places the redirected category as a subcategory -- this is not taxonomically correct.
• #REDIRECT [[:Category:Businesspeople]]
  • This apparently breaks redirection

Are there any better methods that create a redirect without subcategorizing the redirecting page? ~ Stevesliva

One would believe that #REDIRECT [[:Category:Something]] should work. So this really seems like a bug. -- 213.187.165.180 11:17, 27 Jan 2005 (UTC)

Addendum: Seems like this is already reported as a bug: http://bugzilla.wikipedia.org/show_bug.cgi?id=710

On Meta and Wikipedia a redirect to a category shows the editable text only. To get the full page after being redirected, use the link "Image", or "Category", respectively.

Example please... --FGrose 05:57, 15 March 2009 (UTC)

Display Names

NEEDS TO BE IMPLEMENTED

I've used the alternative sort key thing, but is there a way to specify an alternative display name on the catagory list page? for example, Marilyns. In the context of UK hills, Pillar (Lake District) should really only be listed as Pillar. Similarly Arthur's Seat, Edinburgh should be Arthur's Seat, and Beinn Dearg (Torridon) as Beinn Dearg.

Another example is Scottish Battles were some battles are shown with dates, and some aren't.

If we had alternative display names we could make these pages more consistent. Any comments? Miterdale 16:08, 11 Aug 2004 (UTC)

I just wanted to suggest this. Just an example: York is a city founded by Romans.

• [[Category:Roman Cities]] would list York in chapter Y
• [[Category:Roman Cities | Eboracum]] would list York in chapter E
• [[Category:Roman Cities || Eboracum]] (SUGGESTED!) would list Eboracum in chapter E and link to York - the urgently desired feature. Could you introduce this feature as quickly as possible? 80.134.122.238 00:03, 22 Aug 2004 (UTC)

I too would like to see that feature implemented. I started sorting author pages on wikisource and the way they are currently displayed is really ugly -- (ThomasV on wikisource)

In fact, I suggest something a bit more powerful than that. I would like to have the possibility of setting a display name different from the name of the page AND different from the sorting key. Suppose my page is called "Author:John Locke". I want to list John Locke in chapter L and link to "Author:John Locke", eg: [[Category:Authors|Locke|John Locke]] (SUGGESTED!), where the 1st argument would be the key (for compatibility reasons) and the 2nd would be the display name. -- ThomasV

[[Category:MyCategory|DisplayThisInstead]]
Gives
Categories: MyCategory
Instead of
Categories: DisplayThisInstead
i.e. the syntax is that of a Help:Piped link but is in fact a sort key. Any progress on this front? 139.165.200.31 07:46, 6 April 2006 (UTC)

I am also in desperate need of exactly this. As are a lot of others I'm sure. THIS NEEDS TO BE IMPLEMENTED. I concur with the "[[Category:Songs|Locke|John Locke]]" ay ThomasV suggested. Where it would give greatest flexibility and so in the example it would link to the page it was written on and by put in the category 'Authors' under the Letter L and will display John Locke. Fointy 15:46, 18 August 2006 (UTC)

If you are not too reluctant to tweak Mediawiki code itself, at least some of the desperately wanted functionality can be achieved by a minor edit of CategoryPage.php. Look in the function addPage for following line

 : $this->getSkin()->makeSizeLinkObj( $pageLength, $title );

and change it into

: $this->getSkin()->makeSizeLinkObj( $pageLength, $title , $sortkey );

If a sortkey is used to sort the list in the category page then the value of this key will be displayed in stead of the page title. I agree it's not ideal but it's better than nothing. --tommeke 13:32, 17 March 2011 (UTC)

In case someone wants to attempt this with a more recent Mediawiki version, you're likely to get lucky in CategoryViewer.php where you will want to add a , $sortkey to the end of $link = Linker::link($title).

Do empty categories with no parent completely vanish ?

I met the following problem on french Wikipedia : reading several weeks old messages on some Talk pages, I realized that some category pages had simply been emptied and orphaned (generally for matters of naming coherence e.g. "Ville de Pologne" had been replaced by "Villes de Pologne"). Clearly somebody should bother to ask for their pure destruction -if nobody cares, someone will annex one day or another a Polish town article to "Ville de Pologne" instead of "Villes de Pologne", and it will be a perpetual mess.

I have found no way to find the list of these empty-orphaned (or indeed simply empty) categories : they do not appear as listed under Special:Categories.

Look for an example specially built here from the sandbox. Compare the two categories Category:A test category and Category:A non existent category. The first one I created a few minutes ago, then emptied ; the second one never existed. As you can check, the first one, thought you read its name in blue, is unknown from Special:Categories. How could I find out it exists (of course finding its name in this paragraph is not allowed :-)) ? --French Tourist 16:12, 13 Sep 2004 (UTC)

See the new section Help:Category#List_of_all_categories.--Patrick 09:35, 19 August 2006 (UTC)

Embedding categories in Templates

Is it possible to embed a category (i.e. the list of pages that denote [are members of] the category) in a template without having to manually add them in?

I would find this useful as well. As of now {{Category:Something}} just includes the description part of the category. Any way to include the article listing? --Forresto 16:11, 19 Apr 2005 (UTC)

I would like to second the request for this feature. It would simply navigation in many cases. -- DTM 10:14, 16 Nov 2005 (PST)

I am also curious about this. --MateoP 23:13, 23 January 2006 (UTC)

Yes, using DPL. —Eep² 15:22, 21 August 2007 (UTC)

Filtering with multiple categories

Greetings.

I am thinking of wikimedia for documenting a system, and would like to hve categories such as Systems Administrator, Staff, Public etc.

I would also like to have categories such as Catalog, Email, How To etc

Then I would like to have pages made that list only pages that are in the Public category and that are also in Catalog.

Is this Possible?

Don

It would be awesome if it does. At Wikireason we're trying to figure out how to categorize our debates. It looks like we're going to have to manually create these "union" categories--such as "USA foreign relations" and then place the union categories in more general categories such as "USA" and "Foreign relations". It seems sloppy. I'll go look around Wikipedia to see how they handle things like that. I've never noticed it before. AdamRetchless 13:32, 30 April 2006 (UTC)

Agreed. This feature would be extraordinarily useful, especially if a single category yields a large number of results. It's simply the equivalent of an AND keyword. 15:58, 11 July 2006 (UTC)

Formatting according to Category

What I would like to do display a different background colour depending on the category of the page.

I am new to mediawiki and am not sure of the best approach. I have tried putting <div class="mycat"> ... content ... </div> as the content of the page and then defining #mycat in the stylesheeet. This works fine until I try to edit the page and then it removes the <div class="mycat"> from the content. It is also rather clunky.

Any alternative suggestions would be very welcome.

I have not seen such an automatic deletion of content, can you link to an example?--Patrick 10:18, 5 Apr 2005 (UTC)

Test:

... content ...

Not deleted.--Patrick 10:20, 5 Apr 2005 (UTC)

OK can't get it to misbehave now. Have tried adding divs to other pages and all working as expected, but it definitely disappeared yesterday! Will let you know if I can catch it at it again. http://www.energyscenariosireland.com/wiki

Still like to get it putting in the div automatically, something like this

  [[Category:Local]]

  <div class="<somehow put category in here>">

  rest of content ....

Are you using templates? I'm currently working on a local project with template calls and embeding the catagories in the template. So far I've notice that you can reuse the call to add this information elsewhere from the template to the page that you are creating. Try this... I don't know if it's going to work with the div tag, little too new at wiki.

Template:Test (Create the page with the information below)
  [[Category:{{{1}}}]]
  <div class="{{{1}}}">
  {{{2}}}

Now create a new page calling the template
  {{Test|testcat|this is a test with template}}

Should create this
  [[Category:testcat]]
  <div class="testcat">test is a test with template

Please let me know if this helps. FreRange 00:24, 14 July 2005 (UTC)

Edit

Why does the link to all categories under the article link to the editing of the category? I have filled the category with contents to test but it still links to the edit page?

A category typically has an editable part, containing at least a category tag of a supercategory; if it does not, the link to the category page is treated as a link to a non-existing page, hence it is a link to the edit page. I haved clarified that.--Patrick 07:00, 11 Apr 2005 (UTC)

Why not go show the category page, instead of the edit page? The useful content is the articles listed under the category, not usually the editable part of the category page.... --Forresto 06:37, 18 Apr 2005 (UTC)

On one hand you are right, it suggests wrongly that following the link does not provide any info and that the category is not in use; on the other hand, it is a reminder and incentive to at least create a category tag of a supercategory.--Patrick 08:47, 18 Apr 2005 (UTC)

On the third hand (?) the red edit link keeps getting stuck in the cache, which means that even though I have given the category a supercategory it doesn't come through for a while :( --Forresto 16:18, 20 Apr 2005 (UTC)

Okay, fine. So a category HAS to be a member of a higher level category or it won't be created yes? So when the categories spiral upwards how do you create the very top level category? There has to ultimately be on, so how do you get that to stick? Ben W Bell 10:14, 13 May 2005 (UTC)

Excluding Template: namespace pages from category listings?

I have found it very useful to include [[Category:Xyc]] links in various templates, but then the Template: page shows up in the category listing, which is not ideal for users. Is this by design? How can I restrict category listings to articles? --Forresto 06:49, 18 Apr 2005 (UTC)

I think these listings are useful for people who edit and are familiar with templates, although not at a convenient position, alphabetically at the T between the articles. For other people I agree this is confusing "behind the scenes" info.--Patrick 08:55, 18 Apr 2005 (UTC)

I just use the alternate sorting key ala [[Category:Template|~]] which throws any templates at the end of the list so they are still handy but not intrusive. -- Jackdavinci 16:09, 22 Apr 2005 (UTC)

If I understand what you mean, I don't think that helps; as the page says:

A sort key in a category tag in a template applies to the template as well as to the pages that use it, so it does not prevent listing of the template between the rest, and may even make the order random on the category page.

--Patrick 20:50, 22 Apr 2005 (UTC)

I do not think this Problem (or feature9 can be solved, unless a change in the program is made about cathegory. You should contact a developer or, even better, put a request in bugzilla. AnyFile 21:39, 22 Apr 2005 (UTC)

Bugzillaed here: http://bugzilla.wikipedia.org/show_bug.cgi?id=1985 --Forresto 14:51, 26 Apr 2005 (UTC)

Stop the category link move

Is there a way to stop the category text move to a stub? I'd prefer that the category tag not move but just become a link when I place it in my templetes..

Thanks FreRange 00:27, 14 July 2005 (UTC)

Removing alphabetical headings for sub-categories?

For categories with only a few sub-categories, it seems unnecesarry to have the sub-category letter headings (A B C etc). Is there a way to remove these headings gracefully? --82.71.110.82 20:24, 13 October 2005 (UTC)

Sorting by other methods

It appears that I can only sort category articles in alphabetical order. I would like to create a sort of news site, where it's desirable to sort articles in chronological order. Is that possible to do?

The headers are just letters, but through sortkeys they can correspond to chronology.--Patrick 11:23, 11 November 2005 (UTC)

I also have a site where I need my categories to sort by Year (1999, 2003, 2004, 2005, etc). The way it is now, they come under a heading of '1' or '2' which just looks ugly. [[1]] Any chance of a change in a future release? To clarify, this is about the Headings, not the sort order. The order they sort in is fine. It's just having the 2 headings wihch is ugly as sin. -- Jaeneva 11 December 2005

Moving a category page

"The only way to move a category page is to manually change all category tags that link to the category, and copy the editable part. There is no automatic way to move a category page in the way one moves an article page."

As an administrator in 5 wiki sites, including English and Chinese Wikisource, I wonder why we cannot allow categories to be redirected or moved. It is creating more and more problems at many wiki sites. At English Wikisource, for example, s:Category:Law by country should be better changed to "Laws by countries", and "Public domain" and "PD" mean the same thing but they cannot be easily merged. Manual changes will not move histories.

Can we eventually allow categories to be redirected or moved? Current situation is inconvenient.--Jusjih 06:28, 9 December 2005 (UTC)

• People often use bots to easily recategorize mass numbers of articles. According to en:Template talk:Category redirect:

Q: Why not just use a regular redirect?

• A: That is the ideal solution. However, the MediaWiki software currently has issues with categories and redirects:

• #REDIRECT [[Category:Whatever]] does do the redirect, but the original category is listed as a subcategory of Whatever.
• #REDIRECT [[en:Category:Whatever]] works, too, with the same problem as above. Also, this (technically) transwiki redirect fails to send the "redirected from <wherever>" message, which is needed for maintenance.
• #REDIRECT [[:Category:Whatever]] doesn't work at all.
  • Actually, it seems to work now (at least on the Dutch wiki). I guess the bug is fixed. – gpvos (talk) 10:18, 2 October 2005 (UTC)
  • it seems to work in English wiki also, but of course the "old" category can still "collect" new members - j-beda 17:34, 16 May 2006 (UTC)
• #REDIRECT [{{SERVER}}{{localurl:Category:Whatever}}] doesn't work either (and even if it did, it would be a terrible hack).

Hope that helps! Rachel 21:38, 9 August 2006 (UTC)

Renaming Category

I would like to rename the Category feature to something more intuitive like "Index". I have seen it done before, but I am not sure how to go about doing it. Any feedback would be very appreciated. --Palarran 21:57, 12 January 2006 (UTC)

I just went looking for the same info! Got answer here but am reproducing it here for completeness:

The text can be changed by editing MediaWiki:Categories, the link by editing MediaWiki:Pagecategorieslink - on your wiki, of course. If those (pseudo-)pages do not exist, simply create them with the content you want. You may have to flush the parser cache to see the effect, no sure - for testing, use the edit preview mode (that's never cached), to purge all pages, simply touch LocalSettings.php. -- Duesentrieb ⇌ 16:02, 3 March 2007 (UTC)

Thanks so much! I don't know why I couldn't find those before on Special:Allmessages -- but now that I see them, I also see that what I probably need is MediaWiki:pagecategories rather than MediaWiki:Categories. 75.30.114.204 17:25, 3 March 2007 (UTC)

Non-displaying categories

Here's a question for y'all, one I searched for an answer for in vain in all the help pages I could find:

Is it possible to make a category not display on the page on which it appears, but otherwise have all the properties of a category?

I'm actually asking this for another wiki-type project (http://camerapedia.org), so another related question is whether or not the software that drives that site works the same way as that on Wikipedia.

See http://camerapedia.org/wiki/Special:Version --Patrick 10:13, 16 August 2006 (UTC)

Anyhow, this comes up because of a categorization scheme we've implemented there, where we've organized cameras into an alphabetical index. The categories have exciting names like "A", "B", etc. So on each page's category list, there's a little letter entry which is really of no use. I'd like to find a way to suppress its display. --66.52.186.134 20:38, 4 March 2006 (UTC)

See Help:Category#Comparison with "What links here" for a kind of pseudo-category.--Patrick 10:17, 16 August 2006 (UTC)

Order of categories on namespace article

I'm new to wikimedia, but I've notice some controversy on the order in which categories are placed on an en.wikipedia page. The usual standard seems to be alphabetical order with the dates of birth and death at the top, but some are changing pages around with the dates at the bottom and categories organized by related subject. I haven't found a standard in the Manual of Style. This would be helpful. Doc 15:47, 2 May 2006 (UTC)

• Hi. The issue of whether birth and death dates should be first or last is still debated (I personally prefer last since I think these categories are least likely to be used). Additional categories are rarely alphebatized in favor of placing them in order of "relevance", which is subjective. According to en:Wikipedia:Categorization of people, "There is currently no consensus about the order in which these categories should be placed at the bottom of an article." -- Rachel 21:31, 9 August 2006 (UTC)

listing parameters

I know that articles are listed in cateogries under the headings of * 1 2 3 A B C a b c etc. Is it possible to force more than once character to show? Then articles could be sorted in one category under 1790 1791 1792. Right now, they will all show under "1" when given a four digit year sort key... Rachel 21:21, 9 August 2006 (UTC)

How to see total number of items in Category

Is there a variable or other way to see how many items are in a category? If there are more than 200 (the limit for one page), it doesn't tell you the total. For example, w:Category:Wikipedia bots currently shows 4 categories and 196 articles, but you can't tell how many more articles there are. --J. J. 14:33, 25 August 2006 (UTC)

I see that Special:Categories will give the exact number, but this is quite inconvenient. I also see that Bugzilla:1212 has been open since the end of May on this issue! FYI, Bugzilla:4540 is a request for a template to show the number of articles in a category. --J. J. 15:21, 25 August 2006 (UTC)

Can I use different skins for different categories?

I have recently installed a wiki software on my site. I would like to use it for a few projects/ categories. Can I set a different skin for each Category/project and how?

How to force higher article counts in categories?

Hi, we've recently uploaded a wiki at our website and use it to categorize music bands and projects in regard of forming year, location, etc. In our main Category called artists we have already more than 200 articles. I checked the MediaWiki help, the configuration pages, the special pages, etc. Is there a way to avoid the page break? I mean at the moment we have two pages for the category, each containing a maximum of 200 articles. But we would like to have only one page showing always all entries without breaking at 200. This also counts for the subcategories. If you have more than 200 articls, but only one subcategory starting with "z", it's on page 2, but we would like to have it on page one. Hope someone knows a workaround. Rock on!!! - Azchael, December 9th, 2006, www.rockinchina.com (esp. not set us a link) :-)

See $wgCategoryPagingLimit. For example, in your LocalSettings.php you could add "gCategoryPagingLimit = 32768;" and you Category view would not page for more than 32768 articles. --NoahSpurrier 09:48, 5 October 2008 (UTC)

rewording Category considerations?

Any chance of taking "but it may be wise not to put a page in a category and also in a more general category." and using stronger language. I'm getting tired of seeing articles in an example-parent-category and in subcategories of that example-parent-category. --EarthFurst 08:59, 27 December 2006 (UTC)

The formulation is cautious, because it depends on the conventions of a project.--Patrick 15:54, 27 December 2006 (UTC)

Category redirect abuse question

"Redirecting a category page is possible, but almost certainly won't have the desired effect (it can be abused for other purposes)." Such as...? --WikiSlasher 00:10, 3 March 2007 (UTC)

Category structure

The following was added by W!B:, but the content rather seems to belong to the convention of each project. Actually, Wikipedians at JAWP have pointed out that this statement conflicts with categorization policy in JAWP. Therefore I removed from the main text.

Besides cycles, there is another numerous error:

• 
  Don't create links like this red arrow!
• 
  either remove it, or a category in between was missing..
• 
  of course, different branches may have different depth

--Aotake 02:11, 3 July 2007 (UTC)

DefaultSort

This may be the wrong place for this discussion, so please let me know if/where I should move it.

Is there a way the DEFAULTSORT could apply itself to both an article and it's talk page? That way Alan Turing would show up in the "T" section for "Category:English philosophers" and "Category:GA-Class Computer science articles".

Thanks -- SatyrTN 15:15, 3 July 2007 (UTC)

Finding a document by Type or Date

Hi, I have recently installed the MediaWiki Software for a company and have a question: (If this isn't the right section for my question let me know)

Let's say the following documents are added to the Wiki:

• Report New York 1 (dated 1 october 2007)
• Report New York 2 (dated 7 october 2007)
• Report Chicago 1 (dated 1 october 2007)

Now, I'de like to make it possibile for the users to search these documente by City, and by Date.

In other words have:

• a page with a list of Cities, each of which containes the documents of that city.
• a page with the list of dates specified in the title of the document. By clicking a date you access to all relative documents.

How do you suggest I create this structure? Thank you.

(11 october 2007 by Luigi De Micco)

You could make a category for each city and also for each date. However, that way the documents of each city are in a separate page. Perhaps you need one of the extensions, e.g. mw:Extension:CategoryTree.--Patrick (talk) 11:46, 11 October 2007 (UTC)

If the list does not have to be created automatically you can make a sortable table with a city column, a date column, and a column with a link to the document.--Patrick (talk) 11:40, 11 October 2007 (UTC)

Category sort does not work for me

I am using WikiMedia for my wiki in russian language. The letters in the alpabet indexes generated for categories are sorted in wrong order:-( What could be wrong? What settings do I have to make for proper operation? Thanx! 10:16, 12 October 2007 (UTC)

Namespace Prefix

Under Point 3 'Category page' is stated, that since MediaWiki 1.5 in Category listings the Namespace Prefixes are not shown anymore. I have MediaWiki 1.6.3 and the Namespace Prefixes are still shown. :-(
What do I have to do, that they disappear? I'm very thankful for any help!
My Wiki: Harbinger Wiki, related Category Players. (I have made a workaround, which I do not like, so the problem does not appear on every entry atm)
83.77.223.52 15:04, 30 October 2007 (UTC)

Custom Namespaces

I find the paragraph about Non-main namespcaes a little confusing. I have several articles in a custom namespace (custom1:) that are assigned to a category (Subcategory1). Now in the Category:Subcategory1 page all the articles are listed starting with the Custom1 namespace.
How do I hide the namespace on every article name so articles are listed as Article1, Article2 etc. instead of Custom1:Article1, Custom1:Article2 ? Joymonkey 14:36, 16 May 2008 (UTC)

I can't find it in mw:Manual:Configuration settings, so the namespaces where the prefix is left out may not be selectable.--Patrick (talk) 14:57, 16 May 2008 (UTC)

Database error

Hi. I'm getting an error with trying to edit categories. If i click on a link to go to a specific category page, this error message pops up "A database query syntax error has occurred. This may indicate a bug in the software. The last attempted database query was: (SQL query hidden)from within function "CategoryViewer::doCategoryQuery". MySQL returned error "1176: Key 'cl_sortkey' doesn't exist in table 'wiki_categorylinks' (localhost)". Any ideas? I have not edited anything in the MySQL database. Any help would be appreciated. Thanks so much --Pflaherty 20:30, 7 December 2007 (UTC)

Try running maintenace/update.php. MaxSem^{(Han shot first!)} 20:37, 7 December 2007 (UTC)

Thanks so much for the reply. I ran update.php. It came back with this message "Checking if categorylinks index cl_sortkey includes field cl_from... ...index cl_sortkey on table categorylinks has no field cl_from; adding Query "ALTER TABLE `wiki_categorylinks` DROP INDEX cl_sortkey, ADD INDEX cl_sortkey(cl_to, cl_sortkey, cl_from) " failed with error code "Can't DROP 'cl_sortkey'; check that column/key exists (localhost)"." --Pflaherty 00:13, 8 December 2007 (UTC)

Hidden Categories

There is a snippet in Help:Category#Putting_an_item_in_a_category that explains the use of __HIDDENCAT__ to hide categories, with a brief claim that "they can be made visible or invisible through CSS". How is the latter achieved? Specifically, suppose a category has been hidden so it doesn’t clutter the categorised pages: how does one make the category visible within the Category namespace? Urhixidur 20:14, 29 February 2008 (UTC)

Never mind. Experimentation reveals this works a little differently from expected. I’ll update the help accordingly. Urhixidur 20:20, 29 February 2008 (UTC)

Reason for hiding categories?

What is the reason to add this hidden category tag into a page? I cannot find any reasons or ... rules for that. --RokerHRO 17:58, 24 October 2008 (UTC)

The reason would be to not clutter the list of categories on the bottom of a page with the names of categories that are only used for, say, adminstrative purposes. --77.75.161.35 16:58, 18 November 2008 (UTC)

Disabling Thumbnails of Media Files on Category page?

Is there an easy way to disable the thumbnailing of media files within a category without disabling it on all pages? $wgCategoryMagicGallery set to false disables thumbnailing and gives listing on all category pages. —The preceding unsigned comment was added by 4.22.69.25 (talk • contribs) 19:23, 7 May 2008 (UTC).

Just add the magic word __NOGALLERY__ to the category page. Regards, Korg 10:21, 8 May 2008 (UTC)

A short list of Subcategories should not display A,B,C,... "chapter titles"

When the number of subcategories is small (say, fewer than 25 or 30) it is a terrible waste of white space on screen to have the bulleted list of Subcategories display a so-called "Chapter title" (i.e. A, B, C,.. etc.') above each subcategory name.

How complex would it be to set a threshold and trigger for displaying/not displaying those space-hungry "chapter titles" and base it on the number of subcategories in the list?

It is annoying when a Glossary of 150 or so terms is to be displayed along with as few as 5 subcategories. The nicely formatted, multi-column list of Articles in category XYZZY gets pushed off the bottom of the browser window by the preceding list of Subcategories even though there are only 5 subcategories in that list!.

I am relatively new to wiki markup so if there are tips & tricks for customizing the format of automatically generated category pages then please guide me to some useful articles.

(Najevi 13:19, 10 May 2008 (UTC))

Link to category page w/o adding to category

Is there a way to link from an article to a category page without the article being added to the category? --77.75.161.35 17:00, 18 November 2008 (UTC)

To prevent the link to be interpreted as a Category, prefix it with a colon:

[[:Category:MyCategory|Link to MyCategory]]

Category Member Count Wrong

We (my work) have got MediaWiki 1.13.2. Is there a known defect on the Special:Category page? The number of members is usually wrong, far lower than it should be. Is it anything to do with an upgrade (we recently upgraded from 1.12)? Help is very welcome. --Robinson Weijman 16:29, 10 December 2008 (UTC)

Is there a way to add some text to all categories?

I'm trying to use MW:Extension:PdfBook, which says that I can add the following to the Mediawiki:Categoryarticlecount page to have a "download this selection of articles as a PDF book" link appear on every Category: page:

[{{fullurl:{{FULLPAGENAMEE}}|action=pdfbook}} download this selection of articles as a PDF book]

However, my Mediawiki:Categoryarticlecount page was nonexistent before I created it, and nothing I add to that page appears on a normal Category: page. I have tried refreshing Category: pages via a Null edit, but nothing changed. Is there a way to add text to all categories, without having to manually include it in each category or manually transclude a template to each category?

Adding to category without existing page

Is there a way to add a page to a category without the page itself existing? I'm interested in making placeholders for categories on a wiki I maintain, until the page proper is up and running. --66.189.31.110 04:04, 11 June 2009 (UTC)

Subordinate thumbnail gallery to list of articles and sub-categories on category pages

Is it possible to have the "Magic Gallery" shown only _after_ the whole list of articles and sub categories is displayed? Currently in categories with many images, the thumbnail gallery seems to have higher priority to the list of articles. Example On this category page only 11 of 65 articles, zero subcategories but 189 images are displayed.--78.51.148.12 09:17, 26 July 2009 (UTC)

Counts of member file/page/subdirectory elements in categories

On Wikimedia Commons, the number of files/pages/subdirectories in a directory is instantly visible (5 C, 10 F, 20 P etc), and we'd love to add this to Wikitravel (currently MW 1.11.2). Is this is a new core Mediawiki feature, or does it require some extension? Jpatokal 05:50, 24 September 2009 (UTC)

Multiple columns look bad with few pages/subcategories...

Hello,

Basically, I had 6 subcategories in my category (all listed as [[Category:Category| ]] so they would not ). I just added a seventh, and now it has gone into three columns. Previous to this seventh subcategory being added, it was a beautiful list with just the one column.

Is there a way of making the list of subcategories only have one column? I can remove one of the subcategories (which should fix it), however when I add more subcategories (50/50 chance), it will just be ruined again...

Thank you, Metalmiser 05:22, 13 April 2010 (UTC)

Manual Sorting

Is there any way for me to manual sort the order in which the pages show up in the category page (and Category Tree). Its not chronological (ie by date).... but it still has an order (like a textbook with various sections and chapters)

Use sorting keys: for any inclusion of Category:CatToSort write it on the included page as [[Category:CatToSort|SortingKey]]. RYFM.--Ignatus 20:35, 15 January 2012 (UTC)

Chinese support

Unfortunally i am not able to find an way to get Chinese support when using format=html Any suggestions??
[[http://server/index.php?title=Category:Category&action=pdfbook&format=html Click on this link ]]

Alphabetization seems to have changed?

This page and several others all still say that the Categories pages order sort keys with upper case first, lower case second--that is, A, B, ... Z, a, b, ... z. I found that very useful for several things, mostly for making categories of species in a particular genus much more readable. But a few months ago, that seems to have change. It's a pity, in my opinion, but if the change is permanent, it would be good if the instructions would change, too. 140.147.236.195 18:28, 21 September 2011 (UTC)Stephen Kosciesza

Can I add any text under category items?

Writing anything to category page brings it above lists of items. Can I use any magic word to put something under it (just above overcats section)? Want sth like this:

Category:Gory cats

Here you add pages and categories of gory cats.

Main page: Gory cat

Subcategories

---

[+] Cats cut in pieces

[+] Cats with skin off

Pages in category "Gory cats"

---

*

• Gory cat

T

• Tom who had stolen my meat

P

• Pussy who had stolen my fish

<!--HERE:--> Related categories: Cat killing machines | Cat eaters | Cat anatomy

Categories: Gory animals | Shock content

These categories are related to that one, but not so close as to display them on top, I think. Ignatus 20:59, 15 January 2012 (UTC)

Are subcategories unique?

One thing that is unclear from the Help page is: Are subcategories unique?

For example, in the following situation:

• Comic characters
  • Superman
  • Batman
    • Batman (Bruce Wayne) [article]
    • Batman (Azrael) [article]

• Comic series
  • Superman
  • Batman
    • Detective Comics
    • Legends of the Dark Knight

...will clicking on the "Batman" category under "Comic series" take me to a different "Batman" category (ie. Comic Series: Batman) than if I click on the one under Comic Characters (ie. Comic characters: Batman)? (And yes, arguably I should call the categories Batman (Character) and Batman (Comic Series) but it's an example).

Thank you. -- 58.107.64.190 07:43, 16 April 2012 (UTC)

I think you'd have to name the categories specifically "Batman (Character)" and "Batman (Comic Series)" otherwise they'd be the same category.

Any way to sort under multiple sort keys?

I spend most of my time lately on the EN Wiktionary adding and editing Japanese entries. These present a real problem for categorization in the wiki, as a single spelling may have multiple pronunciations, and Japanese dictionaries generally index by pronunciation.

Example:

The Japanese male given name spelled 靖 could be read variously as, and should be indexed under, all of the following:

1. はかる (Hakaru)
2. きよし (Kiyoshi)
3. のぶ (Nobu)
4. おさむ (Osamu)
5. せいじ (Seiji)
6. しずむ (Shizumu)
7. やす (Yasu)
8. やすし (Yasushi)

However, due to the limitations of how category sorting is currently implemented, the 靖 page can only ever be indexed under one listing at wikt:Category:Japanese_male_given_names. The workarounds that folks have come up with include creating empty pages redirecting to the intended entry page, and using the same entry headword plus some non-rendering character, but this is cludgy at best, and is increasingly untenable for each additional index.

Is there any clean way of categorizing a single page under multiple category indices? If not, could this feature be added in a future version of the MW software? -- Eiríkr Útlendi │ Tala við mig 19:04, 29 May 2012 (UTC)

Displaying hidden categories by preference setting

How do I set my preferences to display hidden categories? --Dthomsen8 (talk) 10:52, 23 August 2012 (UTC)

Fixing recent edits

Recent edits from Pierpao need fixing for encyclopedic style and perhaps accuracy and completeness. Bobogoobo (talk) 07:39, 26 June 2013 (UTC)

Why do my pages that have categories mentioned in them, show the same categories like 6-7-multiple times?

Example, look at the bottem of this page and you'll see what I mean: http://wiki.laptop.org/go/Economic_Model_and_Calculator_capable_of_calculating_what_are_the_Additional_Tax_Revenues_from_an_OLPC_XO-XS_deployment Thy --SvenAERTS (talk) 14:30, 3 August 2013 (UTC)

View all from category

Hi...I want to list all Pictures in Category:Paintings plus all pictures in one of its sudirectories in some kind of gallery. Is this possible? Generator (talk) 14:00, 27 August 2013 (UTC)

Moving subcategories down in a category page

Is there anyway to get subcategories section to display underneath/below the pages section listed in a category page? In other workers, is there a way to have it shoe the pages that belong to a category, then underneath it, subcategories (currently it goes subcategories then pages)..? Lestatdelc (talk) 05:59, 12 November 2013 (UTC)

Moving a category

The article says, "The only way to move a category page is to manually change all category tags that link to the category, and copy the editable part. There is no automatic way to move a category page in the way one moves an article page."

That is not correct on Commons. The Cat-a-lot gadget will allow you to move everything on a category page -- all the subcats, pages, and files -- to another category with three or four mouse clicks, so all you have to do manually is create the new category with its parent cats. I see that Cat-a-lot is not available on WP:EN, and I'm not a Wiki software guru, but I assume it could be available on other projects besides Commons.      Jim . . . . Jameslwoodward (talk to me) 20:28, 10 December 2013 (UTC)

IEG proposal on category systems in WMF wikis

I have submitted a proposal for an Individual Engagement Grant for the first phase of a project looking at the category systems in Wikimedia wikis. In this first phase I will research the nature of the English Wikipedia's category system, as the first step in designing ways to optimize category systems throughout WMF wikis. In later phases, I plan to

• Research how readers and editors utilize the category system in the English Wikipedia.
• Investigate the category systems in other language Wikipedias and in other WMF projects.
• Explore the value and feasibility of using Wikidata as the basis for the category system across WMF wikis. If deemed appropriate by the community, work with the community to develop and implement this.
• Utilize user-centered design methodologies to prototype various enhancements to the category system to improve the user experience. If deemed appropriate by the community, work with the community to develop and implement such enhancements.

If you would like to endorse this proposal, you can do so here. I would also appreciate any other feedback, pro or con, which can be posted here. Thanks! Libcub (talk) 06:47, 7 April 2014 (UTC)

Categorize and Link

You can categorize the article with [[Category:Topic]] and you can link to the category page with [[:Category:Topic]] The latter statement does not categorize the article.

Is there a way to do both in a single statement?

Typing [[:Category:Topic | topics]] provides a link to the page with customized text. Typing [[Category:Topic | topics]] categorizes the page but shows no link (regardless of customized text after the pipe). Is this a nonexistent feature and do we need to input both statement

Yes absolutely. In your example "text" after the pipe in changes the sorting position of the containing pages in category:topic. see Help:Category#Sort_order--Pierpao (talk) 06:33, 22 May 2014 (UTC)

Display style of a page's Categories on the page

When I go to Wikipedia or this wiki, the list of categories at the bottom of a page is in a single line. For example:

Categories: Foo | Bar | Baz

But on my own mediawiki, categories appear as a bulleted list:

Categories: 
* Foo 
* Bar
* Baz

I would much prefer the single-line display style. The bulleted format doesn't work for me. How do I get single-line category display?

I assume it's something to do with the wiki skin and/or modifying the CSS, but I can't figure out where to change this, or what to search for. How do I do this? Thanks!

Are you sure? Please look at main page bottom and check? Anyway if you want the standard css go to - preferences - appereance - and check vector.--[User:Pierpao|Pierpao]] (talk) 07:11, 8 August 2014 (UTC)

Yep, I'm sure. The main page is not a part of any categories, so I don't know what to check there. And I want to use my preferred (self-designed) skin, just with single-line categories. How do I accomplish that? Thanks!

I see the main page in Categories:

• Main page/en
• English
• EN

I suggest to check vector, so if vector goes fine the problem is your self designed skin--Pierpao (talk) 21:26, 8 August 2014 (UTC)

I think you're not understanding what I'm asking for. The problem is not the particular categories ("Foo", "Bar", "Baz" are fake place-holder names, not actual categories from my wiki), but how they display. I want the categories to display in a single line, not as a bulleted list. My wiki skin is based on another, standard skin, so it's not a problem with the skin; it's that somewhere, there's a variable or bit of code that sets the display of categories so they're either in a bulleted list or in a single line. I'm trying to figure out what that variable or bit of code is. Does that make sense?

Try to ask here Help Forum--Pierpao (talk) 05:57, 9 August 2014 (UTC)

Problem with category display in MonoBook and Vectro

I used MonoBook theme and had the same category display:

-a -d -g

-b -e -h

-c -f

There was 3 columns for list of articles in category. Now (4 March) I see it like

-a

-b

-c

-d

-e

…

There is 1 column. How to deal with it? 83.237.20.121 03:47, 5 March 2015 (UTC)

A few questions understanding the content ..

I do not understand a few statements in the following paragraph:

==Categories and templates==
Templates can make using and maintaining category pages much simpler.
===Adding a category by using a template===
A template can be used to add a page to a category (one specially for this, or one with another purpose as well), usually by placing the category link inside <includeonly></includeonly> tags on the template (e.g. <includeonly>[[Category:category name]]</includeonly>).  When the template is transcluded into the page, the category link becomes active, and the page is added to the category page.  This is useful for categories that have high turnover or many pages included, like cleanup categories, because: 
*it helps keep category lists up-to-date
*it provides a consistent format so that pages end up on the correct category page without error
*it can be easier

>> "one specially for this, .." seems unclear. Maybe the subject could be defined a little better.

>> "usually by placing the category link inside <includeonly></includeonly> tags on the template" - How do you actually place a link "on a template"? Maybe a specific template could be named and/or linked to, to make this clearer.

>> "When the template is transculuded into the page, .." - "Transcluded"?

If it is necessary to add the template itself to the category page as well, the 'includeonly' tags can be omitted, but this is generally not desired.

>> Maybe the function of the 'includeonly' tags could be explained.

==Categorizing redirect pages==
Redirect pages can be categorized. The category tag has to be put in the first paragraph. In the case that the target of the redirect is a section this has to some extent the effect of categorizing the section: through the redirect the category page links to the section; however, unless an explicit link is put, the section does not link to the category. 
On the category page, redirects are displayed with class redirect-in-category, so they can be shown in e.g. italics; this can be defined in MediaWiki:Common.css. See also w:Wikipedia:Categorizing redirectshttp://en.wikipedia.org/wiki/Wikipedia:Categorizing redirects.

>> "The category tag has to be put in the first paragraph." - Of the redirect page? Does a redirect page have more than one paragraph?

>> "On the category page, redirects are displayed with class redirect-in-category, .." - "class redirect-in-category"?

By the way, the comment displayed on the very top of this "Help_talk" page ends in: "This page is used to discuss what to write in Help:Category voice."

The word "voice" in this sentence does not really make sense to me. Is it a mistake?

thank you, KaiKemmann (talk) 12:39, 9 December 2017 (UTC)

Catgraph

Dapete's category-visualizer Catgraph will render charts of the tree structure: "The requested resource is not available". --Fractaler (talk) 13:33, 28 February 2018 (UTC)

Category structure (category tree) = taxonomy?

Help:Category#Category considerations: "The category structure should reflect a hierarchy of concepts, from the most generic one down to the very specific". What (scientific) laws should be used when creating a category tree? --Fractaler (talk) 10:42, 2 April 2018 (UTC)

Mention that &action=render will not show hidden categories

Mention that &action=render will not show hidden categories, and workarounds. Jidanni (talk) 02:45, 25 February 2019 (UTC)