User:WikiaSphinx/Sandbox/Shared Repository

Rough translation of http://ru.community.wikia.com/wiki/Справка:Общее хранилище файлов

Shared files repository allows a wiki-project to use the files of another wiki-project addressing directly a file by its name. Wiki configuration doesn’t allow the use of files from other sites by default without uploading them.

How does it work?
“Merging” of repositories grants a wiki access to the database of another wiki. As a result, when addressing a file which doesn’t exist on the wiki the system will try to find it in the “master wiki” and, if successful, will use it. No file duplicates are created on the “subsidiary wiki”.
 * A wiki can use only one additional database
 * Merging is a one-way process: “master wiki” shares its files and not vice versa
 * A wiki can grant several other wikis access to its files simultaneously
 * Consecutive merging is possible, but each “subsidiary wiki” will have access only to its respective “master wiki”
 * Categories used on “master wiki” will not be available on the “subsidiary wiki”

Several drawbacks of the described solution should be noted:
 * Thumbnails for images from master repository are not created in gallery-categories
 * Images from master repository are not indexed by subsidiary wiki and can not be added to a page from visual editor

Whom do I contact to get repositories merged?
To get repositories of several wikis merged one should contact the Wikia staff with the help of the contact form or the Wikia Helpers. Request should state the “master wiki” and the “subsidiary wiki” as well as confirm the consent of the wiki editors to get repositories merged.

Can the database of my wiki be merged with Wikimedia projects
Wikia licensing allows projects to use the files of Wikimedia projects. It the topic of your wiki suggests an active use of files hosted by Wikimedia fund projects, you may send a merging request to the staff or ask the Wikia Helpres. Learn more about merging on mediawiki.org.

Additional notes (not a part of translation)
Notes are taken from discussion http://mlp.wikia.com/wiki/Forum:Merging_media-storage#Info_about_merging
 * It usually takes some days from sending a request to get repositories merged
 * It may be a good point to have the first image in an article (or whichever you consider represents the article best) uploaded to "subsidiary wiki" too - to have it representing the article in category galleries and "See also" sections
 * If the name of an image on the "master wiki" is changed the uses of that image on "subsidiary wikis" are supposed to link to the redirection page on the "master wiki". So admins of the "master wiki" should better leave redirection in place when changing the names of the files (this point may need some more testing)
 * If a page on "subsidiary wiki" links an image present with exactly same names both in the "master" and "subsidiary" repositories the local one from "subsidiary wiki" will be used regardless of update time
 * After merging of repositories all files from "master wiki" will be available to the "subsidiary wiki" with no exceptions or a way for a "master wiki's" admin to prevent a file from being used on "subsidiary wiki" (a possible walkaround may be to create a file with exactly same name on "subsidiary wiki")