Help talk:Permanent link
|the Wikipedia Help Project|
Is oldid unique?
It seems oldid must not be unique, since you have to tell it the fullpagename. Is it unique per namespace at least? I should probably go to MediaWiki for this question.
- It is unique. Provided the oldid is valid, the shorter URL
http://en.wikipedia.org/w/index.php?oldid=NNNNNNNhas the same effect. The title is needed so that the software can return a better error message if the oldid refers to a page that has been deleted - compare
- I think this page is aimed at readers, not editors, so it wouldn't be appropriate to mention the templates that format oldids. -- John of Reading (talk) 06:29, 2 April 2013 (UTC)
- The audience is readers, OK. Great.
- The URL missing the ?title parameter says it was "Main page". Maybe the deleted pages always say "Main page". Now I wonder if the software has the oldids in circular files that enact a delayed reuse. (BTW, I found at Help:URL#URLs_of_Wikipedia_pages they say explicitly Note that the version ID is unique across all pages, so the title parameter here has no effect, and can in fact be omitted.) In any case, thank you. — CpiralCpiral 00:12, 3 April 2013 (UTC)
The actual URLs of permanent links to Wikipedia pages (provided by Wikipedia software) have the following long form (including an example):
rather than the [short form:]
The short form saves 13 characters. For instance, I use it in programming documentation because often its lines are limited in length.
I notice that the short form isn't browser-redirected to the long form. Therefore the short form is no less efficient in terms of HTTP (I'm sure).
There may be URL *rewrites* happening locally in Wikipedia's webserver software (such as Apache) but I'm sure its processing time is *extremely* trivial, relatively speaking. Presumably, furthermore, since most people don't use permanent links, they must only be a *very* tiny fraction of all the web requests to Wikipedia.
Any (hypothetical) extra computer time (spent automatically rewriting the URLs of permanent links) is especially unimportant, relative to the time human beings will spend reading (and cutting and pasting) these permanent link URLs.
Of course, when a person makes a decision to use a permanent link, it is for a special, human purpose such as making a written document. Therefore, many people actually will read these URL strings as text (at least briefly).
Unquestionably, both forms should continue to work when submitted by browsers.
I assume Wikipedia has some good reason to continue to choose the long form when its viewers request new permanent links.
Semi-protected edit request on 9 August 2015
A permanent link (or permalink) is a link to a specific version of a wiki page. Normal links always lead to the most current version of a page, but the permalink leads to the text as it was at the time; the text does not include any edits made since. Unlike the name suggests, the permalink does not show exactly the same page, though, only the main text is guaranteed to be retained. The pictures included in the page are still shown at their most current versions, as are the templates, most notably the boxes with text and images placed in the pages' right-top corner. In other words, the permalink displays what the article would look like today if someone reverted to the revision in question.
Permalink is made by clicking 'permanent link' in the sidebar's toolbox or by accessing a prior version of a page from its Page history tab. Both of these will display that version and the page's URL can be used as the target of the permalink.
|When to use||How to create||Result|
|Linking from anywhere in the Internet.
Linking from the printed publication that is citing Wikipedia.
|Copy the 'Permanent link' in the sidebar's Toolbox.||
|Linking from the inside of Wikipedia (such as from a talk page)||Note the
||a version of Wikipedia:Help_desk page|
|No permalink - just a plain link to the most current version of page||
|This page is referenced from the glossary.|
- Help:Page history#Linking to a specific version of a page for more details of browsing the history of Wikipedia.
- Wikipedia:Citing Wikipedia for more details on how to cite Wikipedia, for which you may need a permalink.
- The most obvious differences are if images that existed at the time are subsequently deleted. They would be shown as red links, and inevitably the layout of the article would suffer.