Help:CirrusSearch

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CirrusSearch is the new search engine for MediaWiki. It features key improvements over the old search engine, LuceneSearch. This page describes the features which are new or different compared to the past solutions.

Frequently asked questions

If your question is not answered here, feel free to ask on the talk page and someone will answer it for you.

What's improved?

The new search engine features three main improvements over the old search engine, namely:

  • Better support for searching in different languages.
  • Faster updates to the search index, meaning changes to articles are reflected in search results much faster.
  • Expanding templates, meaning that all content in an article that's in a template is now reflected in search results.

Updates

Updates to the search index are done in near real time. You should be able to search for your changes as soon as you make them. Changes to templates should take effect in articles that include the template in a few minutes. The templates changes use the job queue, so performance may vary. A null edit to the article will force the change through, but that shouldn't be required if everything is going well.

Search suggestions

The search suggestions you get when you type into the search box that drops down candidate pages is substantively the same with articles sorted by the number of incoming links. Worth noting is that if you start your search with ~ we won't find any articles as you type and you can safely hit enter at any time to jump to the search results page.

ASCII/accents/diacritics folding is turned on for English text, but there are some formatting problems with the result. See 52656.

Full text search

Full text search (the kind that lands you on the search results page) searching in title, redirects, headings, and article text so it shouldn't present any surprises. The big change here is that templates are expanded.

There are some relevant open bugs:

In search terminology, support for "stemming" means that a search for "swim" will also include "swimming" and "swimmed".

Filters (intitle:, incategory: and linksto:)

New search- 6 months later.pdf

We've tightened up the syntax around these quite a bit.

  • intitle:foo
    • Find articles whose title contains foo. Stemming is enabled for foo.
  • intitle:"foo bar"
    • Find articles whose title contains foo and bar. Stemming is enabled for foo and bar.
  • intitle:foo bar
    • Find articles whose title contains foo and whose title or text contains bar.
  • -intitle:foo bar
    • Find articles whose title does not contain foo and whose title or text contains bar.
  • intitle: foo bar
    • Syntax error, devolves into searching for articles whose title or text contains intitle:, foo, and bar.
  • incategory:Music
    • Find articles that are in Category:Music
  • incategory:"music history"
    • Find articles that are in Category:Music_history
  • incategory:"musicals" incategory:"1920"
    • Find articles that are in both Category:Musicals and Category:1920
  • -incategory:"musicals" incategory:"1920"
    • Find articles that are not in Category:Musicals but are in Category:1920
  • cow*
    • Find articles whose title or text contains words that start with cow
  • linksto:Help:CirrusSearch
    • find articles that link to a page
  • -linksto:Help:CirrusSearch CirrusSearch
    • find articles that mention CirrusSearch but do not link to the page Help:CirrusSearch

prefix:

The prefix: syntax in its current form is relied upon for a bunch of functionality so it's been recreated as exactly as possible.

  • prefix:cow
    • Find articles in the content namespaces whose title starts with the word "cow".
  • domestic prefix:cow
    • Find articles in the content namespaces whose title starts with the word "cow" and that contain the word "domestic".
  • domestic prefix:Cow/
    • Find all sub-pages of the article "Cow" in the content namespaces that contain the word "domestic". This is a very common search and is frequently built using a special URL parameter called prefix=.
  • domestic prefix:Talk:Cow/
    • Find all sub-pages of the talk page "Talk:Cow" in the talk namespace that contain the word "domestic".
  • cow prefix:Pink Floyd/
    • Find all sub-pages of the article "Pink Floyd" in the content namespaces that contain the word "cow". The space is now insignificant.

Note that the old rule of having to put prefix: at the end of the query still applies.

Special prefixes

  • morelike:Endothermic
    • Find articles whose text is similar to Endothermic.
  • Talk:Foo
    • Find articles in the talk namespace whose title or text contains the word foo

Did you mean

"Did you mean" suggestions are designed to notice if you misspell an uncommon phrase that happens to be an article title. If so, they'll let you know. They also seem to suggest more things than they ought to sometimes.

Prefer phrase matches

If you don't have too much special syntax in your query we'll give perfect phrase matches a boost. I'm being intentionally vague because I'm not sure exactly what "too much special syntax" should be. Right now if you add any explicit phrases to your search we'll turn off this feature.

Fuzzy search

Putting a ~ after a search term (but not double quotes) activates fuzzy search. You can also put a number from 0 to 1 to control the "fuzziness" fraction, e.g. nigtmare~.9 or lighnin~.1 or lighnin~0.1. Closer to one is less fuzzy.

Phrase search and proximity

Surrounding some words with quotes declares that you are searching for those words close together. You can add a ~ and then a number after the second quote to control just how close you mean. The proper name for this "closeness" is "phrase slop". The default "phrase slop" is 1.

flowers algernon Flowers for Algernon flowers are for Algernon Flowers is a science fiction short story and subsequent novel for Algernon
"flowers algernon" YesY YesY N N
"flowers algernon"~1 YesY YesY N N
"flowers algernon"~2 YesY YesY YesY N
"flowers algernon"~0 YesY N N N
"flowers algernon"~10 YesY YesY YesY YesY

Quotes and exact matches

Quotes turn on exact term matches. You can add a ~ to the quote to go back to the more aggressive matcher you know and love.

flowers flower Flowers for Algernon flower for Algernon
flowers YesY YesY YesY YesY
"flowers" YesY N YesY N
"flowers"~ YesY YesY YesY YesY
"flowers algernon" N N YesY N
"flowers algernon"~ N N YesY YesY
"flowers algernon"~1 N N YesY N
"flowers algernon"~1~ N N YesY YesY

prefer-recent:

You can give recently edited articles a boost in the search results by adding "prefer-recent:" to the beginning of your search. By default this will scale 60% of the score exponentially with the time since the last edit, with a half life of 160 days. This can be modified like this: "prefer-recent:<proportion_of_score_to_scale>,<half_life_in_days>". proportion_of_score_to_scale must be a number between 0 and 1 inclusive. half_life_in_days must be greater than 0 but allows decimal points. This number works pretty well if very small. I've tested it around .0001, which is 8.64 seconds.

This will eventually be on by default for Wikinews, but there is no reason why you can't activate it in any of your searches.

hastemplate:

You can filter pages to just those that use a template by adding hastemplate: to the search. We try to emulate the template inclusion syntax so hastemplate:"quality image" finds pages with Template:Quality Image and hastemplate:":quality image" would find transclusions of the article Quality Image from the main namespace. You can omit the quotes if the template's title you are looking for does not contain a space. -hastemplate: will filter pages that does not contain that template.

You can combine all sorts of fun search syntax to get only middle quality images of china File:-hastemplate:"quality image" -hastemplate:"low quality" incategory:china.

boost-templates:

You can boost pages scores based on what templates they contain. This can be done directly in the search via boost-templates:"" or you can set the default for all searches via the new cirrussearch-boost-templates message. boost-templates:"" replaces the contents of cirrussearch-boost-templates if the former is specified. The syntax is a bit funky but was chosen for simplicity. Some examples:

File:boost-templates:"Template:Quality Image|200%" incategory:china
Find files in the China category sorting quality images first.
File:boost-templates:"Template:Quality Image|200% Template:Low Quality|50%" incategory:china
Find files in the China category sorting quality images first and low quality images last.
File:boost-templates:"Template:Quality Image|200% Template:Low Quality|50%" popcorn
Find files about popcorn sorting quality images first and low quality images last. Remember that through the use of the cirrussearch-boost-templates message this can be reduced to just popcorn.

Don't try to add decimal points to the percentages. They don't work and search scoring is such that they are unlikely to matter much.

A word of warning about cirrussearch-boost-templates: if you add really really big or small percentages they can poison the full text scoring. Think, for example, if enwiki boosted featured articles by a million percent. Then searches for terms mentioned in featured articles would find the featured articles before exact title matches of the terms. Phrase matching would be similarly blown away so a search like brave new world would find a featured article with those words scattered throughout it instead of the article for Brave New World.

Sorry for the inconsistent - in the name. Sorry again but the quotes are required on this one. Sorry also for the funky syntax. Sorry we don't try to emulate the template transclusion syntax like we do with hastemplate:.

insource:

1.24
Gerrit change 137733

insource: will search text just in the wikitext. This will pick up template parameter names, URLs in link tags, etc. It has two flavors:

insource:foo and insource:"foo bar"
These work pretty similarly to intitle: or regular text search in that they are fast but ignore punctuation.
insource:/foo/ and insource:/foo/i
These run Regular expressions against the page source. They aren't efficient and we only allow a few of them to run at a time on the search cluster but they are very powerful. This link contains an explanation of the syntax and this link contains an actual grammar for the Regular Expression language. The version with the extra i runs the expression case insensitive and is even less efficient. Note that if the regexp contains whitespace, you must either escape each space character (\ ) or put everything after insource: in quotes (insource:"/foo bar/").
Tip: These return much much faster if there are other filters. Instead of searching for insource:/self-absorbed/ search for insource:self-absorbed insource:/self-absorbed/.

Auxiliary Text

Cirrus considers some text in the page to be "auxiliary" to what the page is actually about. Examples include table contents, image captions, and "This article is about the XYZ. For ZYX see ZYX" style links. You can also mark article text as auxiliary by adding the searchaux class to the html element containing the text.

Auxiliary text is worth less than the rest of the article text and it is in the snippet only if there are no main article snippets matching the search.

Lead Text

Cirrus assumes that non-auxiliary text that is between the top of the page and the first heading is the "lead in" paragraph. Matches from the lead in paragraph are worth more in article ranking.

See also