Difference between revisions of "Help:Searching"

Revision as of 05:34, 19 July 2006

Search namespace (replace x in the URL by the search term):

all 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15

The result count in the header of the search result is the total for all namespaces; accordingly there are links to supposed other pages with results; correctly a lower number of results is actually presented. (bugzilla:2895)

Search facilities in MediaWiki

This page explains the search button for the search box which appears on every page, and the "Search result settings" section in the preferences.

list of all pages

Special:Allpages - Alphabetic index for the main namespace

Please note that a-z come after A-Z.

For some other namespaces, see Help:Namespace.

Go button

Search field

Pressing the [Enter] key while the search field is active is equivalent to clicking on the [Go] button. While this is obvious when using Internet Explorer (tested on version 6), Mozilla (version 1.6 at least) provides no such indication.

Tips

Avoid short and common words

This is the most likely cause of an unexpected failed search. If your search terms include a common "stop word" (such as "the", "one", "your", "more", "right", "while", "when", "who", "which", "such", "every", "about", "onto"), then your search will fail without any results. Short numbers, and words that appear in half of all pages, will also not be found. In this case, drop those words and rerun the search.

See Help:Common words, searching for which is not possible for the stop words filtered out by the database. From there one can at least go to a page with a stop word as title. Searching for the combination of one or more words and the common word "not" give a database query syntax error due to a bug in the software.

See Help:Short words in searches for a procedure to allow MySQL to index words shorter than four letters.

Search is case-insensitive

The searches for "fortran", "Fortran" and "FORTRAN" all return the same results.

Words with special characters

In a search for a word with a diaeresis, such as Sint Odiliënberg, it depends whether this ë is stored as one character or as "ë". In the first case one can simply search for Odilienberg (or Odiliënberg); in the second case it can only be found by searching for Odili, euml and/or nberg. This is actually a bug that should be fixed -- the entities should be folded into their raw character equivalents so all searches on them are equivalent. See also Help:Special characters.

Phrase

There is no method for searching for a phrase. Contrary to what you might expect, enclosing phrases in double quotation marks such as "can of tuna" will retrieve all pages containing "of" "tuna" and "can".

Searching limitations and Gotchas

No regular expressions or wildcards

You cannot use regular expressions or wildcards such as ? or *. If you don't know what that is, don't worry about it. To search for pages with the words "boat" or "boats" search like this: "boat or boats".

Words in single quotes

If a word appears in a page with single quotes, you can only find it if you search for the word with quotes. Since this is rarely desirable it is better to use double quotes in pages, for which this problem does not arise.

An apostrophe is identical to a single quote, therefore Mu'ammar can be found searching for exactly that (and not otherwise). A word with apostrophe s is an exception in that it can be found also searching for the word without the apostrophe and the s.

Delay in updating the search index

For reasons of efficiency and priority, very recent changes to pages are not always immediately taken into account in searches.

Search Options

Namespaces searched

The search only applies to the namespaces selected in the preferences. To search the other namespaces check or uncheck the tickboxes in "Search in namespaces" box found at the bottom of a search results page. Depending on the browser, a box may still be checked from a previous search, but may no longer be effective. To be sure the box is in effect, uncheck and recheck it.

Searching the image namespace means searching the image descriptions, i.e. the first parts of the image pages. For searching the titles, use Special:Imagelist.

The URL is

http://meta.wikimedia.org/wiki/Special:Search?ns0=1&ns1=1&ns2=1&ns3=1&ns4=1&ns5=1&ns6=1&ns7=1&ns8=1&ns9=1&ns10=1&ns11=1&ns12=1&ns13=1&ns14=1&ns15=1&fulltext=Search&search=qqq

where "qqq" is used as example for the search term, and the namespaces to be searched are specified.

Thus, e.g.

http://meta.wikimedia.org/wiki/Special:Search?ns10=1&ns11=1&fulltext=Search&search=test

searches the Template and Template talk namespaces for "test", and

http://meta.wikimedia.org/wiki/Special:Search?ns6=1&fulltext=Search&search=jpg

searches the image description pages for "jpg".

To search the Help pages use http://meta.wikimedia.org/w/index.php?title=Special%3ASearch&ns12=1&&fulltext=Search&search=x and replace the x in the URL by the search term. Replacing it in the search box does not work the same: the search is then in the namespaces specified in the preferences, instead of just in the help namespace.

The number of search results reported seems to be the total for all namespaces; accordingly there are links to supposed other pages with results; correctly a lower number of results is actually presented.

(Also there is a special search feature Special:Imagelist, which searches in titles, regardless of whether there is an image description.)

Languages searched

See the feature request at MediaZilla:1837.

Redirects can be excluded

Check or uncheck the tickbox "List redirects" in "Search in namespaces" box found at the bottom of a search results page.

The wikitext is searched

The wikitext (source text, what one sees in the edit box) is searched. This distinction is relevant for piped links, for interlanguage links, special characters (if ê is coded as ê it is found searching for ecirc), etc.

Highlighting

Some portions of matching pages that contain the searched-for terms are shown, with the terms highlighted in red. You can set the number of lines extracted and the amount of text per line shown in your preferences.

If you search e.g. for "book" you get only pages with that word, not pages with "books" only. However, on pages with "book" and "books", also the part "book" of the word "books" is highlighted.

Search engines

Google

The URL

http://www.google.com/search?q=site%3Awikipedia.org+%22interwiki+link%22

searches for the phrase interwiki link in wikipedia.org — that is, in all Wikipedias as well as Wikisource (sources.wikipedia.org) and meta.wikipedia.org, but not meta.wikimedia.org.

%3A is a colon (:), %22 a double quotation mark ("), and + is equivalent to a space ( ); %20 may also be used for a space. (See also Help:URL.)

Note that the underscore (_) is not equivalent to a space: putting it in the URL results in a search for a word containing actual underscores at those positions. Thus

http://www.google.com/search?q=site%3Awikipedia.org+%22interwiki_link%22

finds pages containing the term interwiki_link.

Examples

Working:

http://www.google.com/search?q=%22michael+jackson%22

http://www.google.com/search?q=%22michael%20jackson%22

Searching for first term only:

http://www.google.com/search?q=%22michael jackson%22

Searching for two terms, not the phrase:

http://www.google.com/search?q=michael+jackson

http://www.google.com/search?q=michael%20jackson

Searching for phrase with underscore:

http://www.google.com/search?q=michael_jackson

Thumbnails in Google cache

Browse Wikipedia images with thumbnails in Google cache: png jpg gif

Each thumbnail links to an image result page, which links both to the Wikipedia image page and to the image itself on Wikimedia.

Administration Options

from includes/DefaultSettings.php, apparently you have to look up your namespace table, because they are numbered...

$wgNamespacesToBeSearchedDefault = array( -1 => 0, 0 => 1, 1 => 0,
  2 => 0, 3 => 0, 4 => 0, 5 => 0, 6 => 0, 7 => 0, 8 => 0, 9 => 1, 10 => 0, 11 => 1 );

I would guess that -1 is the default settings.. and 0 is main namespace.. and 0 is off and 1 is on.