Symmetric property: if [item A] has this property linked to [item B], then [item B] should also have this property linked to [item A]. (Help)

Exceptions are possible as rare values may exist. Exceptions can be specified using exception to constraint (P2303).
List of violations of this constraint: Database reports/Constraint violations/P2959#Symmetric, SPARQL

Conflicts with “instance of (P31): Wikimedia duplicated page (Q17362920)”: this property must not be used with the listed properties and values. (Help)

List of violations of this constraint: Database reports/Constraint violations/P2959#Conflicts with P31, hourly updated report, search, SPARQL

Scope is as main value (Q54828448): the property must be used by specified way only (Help)

List of violations of this constraint: Database reports/Constraint violations/P2959#Scope, hourly updated report, SPARQL

Conflicts with “instance of (P31): Wikimedia disambiguation page (Q4167410)”: this property must not be used with the listed properties and values. (Help)

Exceptions are possible as rare values may exist. Exceptions can be specified using exception to constraint (P2303).
List of violations of this constraint: Database reports/Constraint violations/P2959#Conflicts with P31, search, SPARQL

Allowed entity types are Wikibase item (Q29934200): the property may only be used on a certain entity type (Help)

Exceptions are possible as rare values may exist. Exceptions can be specified using exception to constraint (P2303).
List of violations of this constraint: Database reports/Constraint violations/P2959#Entity types

This property is being used by: lad:Módulo:Interwiki uk:Шаблон:Infobox occupation/пісочниця Please notify projects that use this property before big changes (renaming, deletion, merge with another property, etc.)

At least one of the items needs P31 = Wikimedia permanent duplicate item (Q21286738)
FIXME: Add missing P31=Q21286738 or remove P2959 (Help)
Violations query: SELECT DISTINCT ?item #?itemLabel ?itemDescription ?value ?valueLabel ?valueDescription { ?item wdt:P2959 ?value . MINUS { ?item wdt:P31 wd:Q21286738 } . MINUS { ?item wdt:P2959 ?value . ?value wdt:P31 wd:Q21286738 } FILTER ( ?value != ?item ) . #SERVICE wikibase:label { bd:serviceParam wikibase:language "[AUTO_LANGUAGE],en" } . } ORDER BY ASC(xsd:integer(STRAFTER(str(?item), "Q")))
List of this constraint violations: [[Wikidata:Database reports/Complex constraint violations/P2959#At least one of the items needs P31 = Wikimedia permanent duplicate item (Q21286738)|Database reports/Complex constraint violations/P2959#At least one of the items needs P31 = Wikimedia permanent duplicate item (Q21286738)]]

Only one of the two items can have P31 = Wikimedia permanent duplicate item (Q21286738)
FIXME: Remove P31=Q21286738 from one of the items or remove P2959 (Help)
Violations query: SELECT DISTINCT ?item #?itemLabel ?itemDescription ?value ?valueLabel ?valueDescription { ?item wdt:P2959 ?value . ?item wdt:P31 wd:Q21286738 . ?value wdt:P31 wd:Q21286738 . FILTER ( ?value != ?item ) . #SERVICE wikibase:label { bd:serviceParam wikibase:language "[AUTO_LANGUAGE],en" } . } ORDER BY ASC(xsd:integer(STRAFTER(str(?value), "Q")))
List of this constraint violations: [[Wikidata:Database reports/Complex constraint violations/P2959#Only one of the two items can have P31 = Wikimedia permanent duplicate item (Q21286738)|Database reports/Complex constraint violations/P2959#Only one of the two items can have P31 = Wikimedia permanent duplicate item (Q21286738)]]

Items for permanent duplicates and English labels
FIXME: TBD (remove them?) (Help)
Violations query: SELECT DISTINCT ?item #?itemLabel ?itemDescription ?value ?valueLabel ?valueDescription { ?item wdt:P2959 ?value . ?item wdt:P31 wd:Q21286738 . ?item rdfs:label ?label . FILTER ( LANG( ?label ) = "en" ) . MINUS { ?item wdt:P31 wd:Q4167836 } . #SERVICE wikibase:label { bd:serviceParam wikibase:language "[AUTO_LANGUAGE],en" } . } ORDER BY ASC(xsd:integer(STRAFTER(str(?value), "Q")))
List of this constraint violations: Database reports/Complex constraint violations/P2959#Items for permanent duplicates and English labels

Items for permanent duplicates and English description
FIXME: replace with "Wikimedia permanent duplicate item" (Help)
Violations query: SELECT DISTINCT ?item #?itemLabel ?itemDescription { ?item wdt:P31 wd:Q21286738 . ?item wdt:P2959 [] . MINUS { ?item wdt:P31 wd:Q4167836 } . ?item schema:description ?itemDescription . FILTER( LANG( ?itemDescription ) = "en" && ?itemDescription != "Wikimedia permanent duplicate item"@en ) . #SERVICE wikibase:label { bd:serviceParam wikibase:language "[AUTO_LANGUAGE],en" } . } ORDER BY ASC(xsd:integer(STRAFTER(str(?value), "Q")))
List of this constraint violations: Database reports/Complex constraint violations/P2959#Items for permanent duplicates and English description

Items for permanent duplicates and statements
FIXME: TBD (remove statements other than P31=Q21286738 and P2959?) (Help)
Violations query: SELECT DISTINCT ?item #?itemLabel ?itemDescription ?value ?valueLabel ?valueDescription ?main ?mainLabel { hint:Query hint:optimizer "None" . ?item wdt:P2959 ?main . ?item wdt:P31 wd:Q21286738 . ?item ?wdt ?value . ?prop wikibase:directClaim ?wdt . FILTER ( ?wdt NOT IN ( wdt:P2959 ) ) FILTER ( ?value NOT IN ( wd:Q21286738 ) ) FILTER NOT EXISTS { ?item wdt:P31 wd:Q4167836 } # skip categories FILTER NOT EXISTS { ?item wdt:P31 wd:Q11266439 } # skip templates #SERVICE wikibase:label { bd:serviceParam wikibase:language "[AUTO_LANGUAGE],en" } } ORDER BY ASC(xsd:integer(STRAFTER(str(?item), "Q"))) LIMIT 500
List of this constraint violations: Database reports/Complex constraint violations/P2959#Items for permanent duplicates and statements

Items with P31 = Wikimedia permanent duplicate item (Q21286738) or P2959 should have at least one sitelink
FIXME: Merge the items, add the missing sitelinks or remove P2959/Q21286738 (Help)
Violations query: SELECT DISTINCT ?item WHERE { { ?item wdt:P31 wd:Q21286738 } UNION { ?item wdt:P2959 [] } . ?item wikibase:sitelinks 0 . } ORDER BY ASC(xsd:integer(STRAFTER(str(?item), "Q")))
List of this constraint violations: [[Wikidata:Database reports/Complex constraint violations/P2959#Items with P31 = Wikimedia permanent duplicate item (Q21286738) or P2959 should have at least one sitelink|Database reports/Complex constraint violations/P2959#Items with P31 = Wikimedia permanent duplicate item (Q21286738) or P2959 should have at least one sitelink]]

Items with P31 = Wikimedia permanent duplicate item (Q21286738) and P2959 should only have sitelinks to multi-langoid or multiscript websites
FIXME: Move sitelink, remove P2959/Q21286738, define Q21286561/Q21286559 or define exceptions (Help)
Violations query: SELECT ?item ?itemLabel ?itemDescription ?site ?wmfsiteLabel ?value ?valueLabel ?valueDescription { ?item wdt:P31 wd:Q21286738 . ?item wdt:P2959 ?value . [] schema:about ?item ; schema:isPartOf ?site . ?wmfsite wdt:P856 ?site . MINUS { ?wmfsite wdt:P31 wd:Q21286561 } . MINUS { ?wmfsite wdt:P31 wd:Q21286559 } . #SERVICE wikibase:label { bd:serviceParam wikibase:language "[AUTO_LANGUAGE],en" } . }
List of this constraint violations: [[Wikidata:Database reports/Complex constraint violations/P2959#Items with P31 = Wikimedia permanent duplicate item (Q21286738) and P2959 should only have sitelinks to multi-langoid or multiscript websites|Database reports/Complex constraint violations/P2959#Items with P31 = Wikimedia permanent duplicate item (Q21286738) and P2959 should only have sitelinks to multi-langoid or multiscript websites]]

Items with P31 = Wikimedia permanent duplicate item (Q21286738) and P2959 should only have links to sites that the other item has as well
FIXME: Move sitelink to the other item or remove P31=Q21286738 if needed. (Help)
Violations query: SELECT DISTINCT ?item #?itemLabel ?itemDescription ?value ?valueLabel ?valueDescription ?site { ?item wdt:P31 wd:Q21286738 ; wdt:P2959 ?value; ^schema:about/schema:isPartOf ?site . OPTIONAL { ?value ^schema:about/schema:isPartOf ?site1 . FILTER( SAMETERM( ?site, ?site1 ) ) . } . FILTER( !BOUND( ?site1 ) ) . #SERVICE wikibase:label { bd:serviceParam wikibase:language "[AUTO_LANGUAGE],en" } . } ORDER BY ASC(xsd:integer(STRAFTER(str(?item), "Q")))
List of this constraint violations: [[Wikidata:Database reports/Complex constraint violations/P2959#Items with P31 = Wikimedia permanent duplicate item (Q21286738) and P2959 should only have links to sites that the other item has as well|Database reports/Complex constraint violations/P2959#Items with P31 = Wikimedia permanent duplicate item (Q21286738) and P2959 should only have links to sites that the other item has as well]]

Items with P31 = Wikimedia permanent duplicate item (Q21286738) should have this property
FIXME: Add P2959 or remove P31=Q21286738, if needed replace P460 (Help)
Violations query: SELECT DISTINCT ?item #?itemLabel ?itemDescription { ?item wdt:P31 wd:Q21286738 . MINUS { ?item wdt:P2959 [] } . MINUS { ?item wdt:P31 wd:Q4167836 } . #maybe as well #SERVICE wikibase:label { bd:serviceParam wikibase:language "[AUTO_LANGUAGE],en" } . } ORDER BY ASC(xsd:integer(STRAFTER(str(?item), "Q"))) LIMIT 100
List of this constraint violations: [[Wikidata:Database reports/Complex constraint violations/P2959#Items with P31 = Wikimedia permanent duplicate item (Q21286738) should have this property|Database reports/Complex constraint violations/P2959#Items with P31 = Wikimedia permanent duplicate item (Q21286738) should have this property]]

Items with P31 = Wikimedia permanent duplicate item (Q21286738) and P460
FIXME: Add P2959 or remove P31=Q21286738, probably replace P460 (Help)
Violations query: SELECT ?item #?itemLabel ?itemDescription ?value ?valueLabel ?valueDescription { ?item wdt:P31 wd:Q21286738 . ?item wdt:P460 ?value . MINUS { ?item wdt:P2959 [] } . MINUS { ?item wdt:P31 wd:Q4167836 } . #maybe as well #SERVICE wikibase:label { bd:serviceParam wikibase:language "[AUTO_LANGUAGE],en" } . } ORDER BY ASC(xsd:integer(STRAFTER(str(?item), "Q")))
List of this constraint violations: [[Wikidata:Database reports/Complex constraint violations/P2959#Items with P31 = Wikimedia permanent duplicate item (Q21286738) and P460|Database reports/Complex constraint violations/P2959#Items with P31 = Wikimedia permanent duplicate item (Q21286738) and P460]]

Illustrates sitelinks on items with P31=permanent duplicates (2 pages on a site = 1, 3 pages on a site=2, etc) Categories are not systematically excluded	For a site, this illustrates how many items have several sitelinks for an item (2, 3, 4, 5 pages on a site = 1). Total here shouldn't be higher than in the other chart ;)
Graphs are temporarily unavailable due to technical issues.	Graphs are temporarily unavailable due to technical issues.

Some items have labels, but most don't. I wonder if label is actually of much use. Isn't it more likely to confuse users? This also avoids lengthy descriptions about not using the item.
--- Jura 05:07, 6 October 2016 (UTC)[reply]

If there is a "permanently duplicate item" description, I don't think the labels do much harm. On the other hand, English labels/descriptions are unneeded. Lymantria (talk) 06:50, 6 October 2016 (UTC)[reply]

I would be in favour of not having English labels on the duplicate items because duplicating information creates more maintenance work to keep the items in sync and increases the chances of someone selecting the wrong item or duplicating more information on the item. If we are going to have English labels, they should match the main item's English label and not the duplicated page's name. - Nikki (talk) 07:55, 6 October 2016 (UTC)[reply]

• With P2959 as one of the few statements on the item, it's fairly easy to figure out what would be the English label. So I think we can safely remove the 100 or something labels.
  --- Jura 10:40, 8 October 2016 (UTC)[reply]
• I skipped the ones for templates.
  --- Jura 11:24, 22 October 2016 (UTC)[reply]

Should this be used on categories, notably the ones for user pages? I think there is some bug that needs to be resolved and these could actually be merged.
--- Jura 05:07, 6 October 2016 (UTC)[reply]

I think: yes. But if merge is possible and the homewiki is willing to - be my guest. Lymantria (talk) 06:48, 6 October 2016 (UTC)[reply]

• I'm not really convinced that they are permanent. Ideally phabricator:T101086 gets fixed and these could be merged. As most other permanent duplicates are different, I had to exclude categories from most constraints above.
  --- Jura 10:40, 8 October 2016 (UTC)[reply]

For the non-user pages categories, I do think they are permanent. I understand you don't think so for the user pages. Lymantria (talk) 16:02, 9 October 2016 (UTC)[reply]

• Ah, in the meantime, I noticed that some Wikis do have several category systems, one for each script .. oh dear. Yes, this would be "permanent duplicates" as well.
  --- Jura 15:26, 20 October 2016 (UTC)[reply]

It seems that Armenian Wikipedia (hywiki) has most links. Some of the ones that follow it have not 2, but even 3 pages for the same.

Wouldn't it be easier to simply split hywiki into 2? Obviously, provided that its users want that.
--- Jura 05:07, 6 October 2016 (UTC)[reply]

That seems hardly a discussion to be held here. BTW, some Northern Frisian pages/categories come in groups of 4 about the same. Lymantria (talk) 06:47, 6 October 2016 (UTC)[reply]

Like Lymantria said, this is not the right place to discuss that, it's a matter for hywiki and its users. You should take into account the size of the wikis when thinking about the numbers. hywiki is much larger than any of the others (except shwiki where the numbers are skewed by bot-created pages) and the duplicates only account for a tiny proportion of pages. Also, just because a wiki has deliberate duplicates doesn't mean there are no accidental duplicates. If there are three pages on hywiki, one of them is probably an accidental duplicate. - Nikki (talk) 07:33, 6 October 2016 (UTC)[reply]

• I'm interested in the opinion of the people who have to deal with the effects of the current situation. From a Wikidata point of view, I think the number of not-bot created pages is an important factor to consider. Obviously, as stated earlier, it depends primarily what its users want it and I'm sure a series of other people that aren't really concerned will voice their opinion as well. This is likely to be a lengthy process.
  --- Jura 10:40, 8 October 2016 (UTC)[reply]

  Eastern and Western Armenian are not eligible for separate projects according to the language proposal policy. If the Armenian Wikipedians do want to split their Wikipedia, they will have to apply for separate ISO 639 codes (with enough evidence to overturn the previous rejection) or convince the language committee to allow separate projects despite not meeting multiple criteria. Neither sounds easy.

  If you want to know whether the Armenian Wikipedians want to split their Wikipedia, you are not likely to find the answer by asking in English on Wikidata. I would recommend finding someone who speaks Armenian who can ask on your behalf on the Armenian Wikipedia. If you're asking whether other people think the Armenian speakers should split their Wikipedia, then what do you hope to achieve? How they organise their pages is completely out of our control, no matter how inconvenient it is for us.

  - Nikki (talk) 16:02, 8 October 2016 (UTC)[reply]

  I think it looks like the problems are mainly in the clients. They have to use arbitrary access to use even the simpliest thing. While we only have to handle that a set of pages cannot be merged. But that is true also when we look into other projects. Wikisource can have the same texts in many items, within one single language/script. Not even when there is only one page per project, Wikisource-texts should always be merged. -- Innocent bystander (talk) 18:40, 8 October 2016 (UTC)[reply]

  • I think when this was first brought up at Wikidata, a user from hywiki suggested they'd rather have two separate ones. Maybe my memory fails me or this wasn't representative, in any case, this part should obviously be discussed elsewhere. BTW, there is now a WikiProject Armenia.
    --- Jura 10:36, 9 October 2016 (UTC)[reply]

@Jura1: Another problem: are items that like Q21200341 and Q20509297 really permanent duplicated? I'm having no possible to find their "duplicated-from" items, only see a blue template. I'm afraid we should define another P31 value for them. --Liuxinyu970226 (talk) 14:22, 26 June 2017 (UTC)[reply]

@Jura1, Lymantria, Nikki, Innocent bystander: Let you all know that Michael Everson submitted the second request for hyw code for Western Armenian and it's approved in 23 Jan. --Liuxinyu970226 (talk) 13:48, 2 February 2018 (UTC)[reply]

There are quite a few duplicates which try to describe the duplicated pages. That limits which other duplicates can be added to the same item.

Examples:

• Q24069316 has a instance of (P31) transliteration (Q134550) statement because the page title is a transliteration (which stops it from being merged with Q25161702)
• Q20829392 has both language of work or name (P407) Judaeo-Spanish (Q36196) and writing system (P282) Hebrew alphabet (Q33513) (which stops it from being merged with Q23653940)
• Canada (Q21287484) and Canada (Q22828365) have the English label set to the duplicate page's name (which stops those two items and Canada (Q27103712) from being merged into a single item)
• Q20514998 has a label explicitly saying it's for the Western Armenian page (which stops it from being merged with Q27114296)
• Q20819981 has a description saying it is for alternative script articles (which stops it from being merged with Q21200811)

Should we be doing that? I would personally prefer to not use statements like instance of (P31) transliteration (Q134550) and not make references to specific languages or scripts, so that we can merge items into as few duplicates as possible.

- Nikki (talk) 08:26, 6 October 2016 (UTC)[reply]

I agree. Lymantria (talk) 12:34, 6 October 2016 (UTC)[reply]

• Most of the time a P31 and a P2959 statement should be sufficient. The other day, I removed some 200 "language = Armenian"-statements from such items.
  --- Jura 10:40, 8 October 2016 (UTC)[reply]

Not all such articles are a true transliteration (Q134550). nn:Hn/Oktav has not exactly the same content as nn:Oktav even if they are about the same subject. -- Innocent bystander (talk) 11:10, 8 October 2016 (UTC)[reply]

• I added a constraint to list statements other than P31=Q21286738/P2959.
  --- Jura 10:36, 9 October 2016 (UTC)[reply]

• I standardized the description of items that had one to "Wikimedia permanent duplicate item".
  --- Jura 15:26, 20 October 2016 (UTC)[reply]

• I think you might want to remove the additional statements.
  --- Jura 11:24, 22 October 2016 (UTC)[reply]

 Done for most statements. I also moved other statements to the main item. A few images remain.
--- Jura 05:25, 28 March 2018 (UTC)[reply]

• With the new search features, the absence of English labels no longer avoids that these come up. I think we should add an English description to all items. Hopefully the new Armenian wiki will soon reduce the number of items.
  --- Jura 05:25, 28 March 2018 (UTC)[reply]

Although I think ruwiki does not qualify to have permanently duplicated items, I tend to think that essentially GB (Q205699) and Q4130663 are. Any thoughts? Lymantria (talk) 16:00, 9 December 2016 (UTC)[reply]

I wouldn't consider that a permanent duplicate, the two pages don't have the same content and there doesn't seem to be any intention for them to have the same content. Other wikis might only have a single disambiguation page covering both scripts, but that would be a case of some wikis having a single page covering two things where other wikis have separate pages for the two things. - Nikki (talk) 21:54, 9 December 2016 (UTC)[reply]

OK. Lymantria (talk) 07:05, 10 December 2016 (UTC)[reply]

Another factor in your sample is that ruwiki isn't a multi-script or multi-langoid wiki.

Eventually, I hope we could automatize maintenance of disambiguation pages: Wikidata:Bot_requests#Take_care_of_disambiguation_items. So one needn't edit them at all.
--- Jura 08:37, 10 December 2016 (UTC)[reply]

That other factor I was aware of, writing "ruwiki does not qualify to have permanently duplicated items". I have my doubts over the effectivity of the bot request. Lymantria (talk) 09:24, 10 December 2016 (UTC)[reply]

Looks like I read this too quickly, sorry about that. About the request: it needn't be. If it incites people to edit other items instead, that might be sufficient. It does outline what needs to be done and could simply become a MW function. One can even vote for that: m:2016_Community_Wishlist_Survey/Categories/Wikidata#Take_care_of_disambiguation_items.
--- Jura 09:47, 10 December 2016 (UTC)[reply]

FYI see phab:T212597. Matěj Suchánek (talk) 15:12, 2 April 2019 (UTC)[reply]

The English description ("this item duplicates another item and the two can't be merged, as one Wikimedia project includes two pages, e. g. in different scripts or languages (applies to some wiki, e.g.: cdowiki, gomwiki). Use "duplicate item" for other wikis.") implies that another property exists for "(non-permanent) duplicate item", but I can't find it. Was it deprecated? —capmo (talk) 15:02, 12 October 2021 (UTC)[reply]

No, see Help:Merge#Items_to_be_merged_with_sitelink_conflicts instead. --- Jura 13:07, 29 October 2021 (UTC)[reply]

Nice, thanks for the tip! —capmo (talk) 12:44, 12 November 2021 (UTC)[reply]

I edited the description to hopefully make this less ambiguous. Waldyrious (talk) 18:38, 5 February 2023 (UTC)[reply]

The description of this property, as well as the various discussions above, suggests that it is meant only for pages from the same wiki that are intended to have the same content represented in different scripts or language variants.

This raises a couple questions:

• First, why not make this language-related aspect explicit in the property name? The "permanent" qualifier is quite vague unless one already knows what it is supposed to mean in this context. Specifically, it explains the "what" —that there is no intention to merge the two pages— but not the "why" —that the reason there are two of them is because the wiki supports multiple scripts or language variants. I am not sure I can think of a better name, but off the top of my head, something like "duplicated item in different script or variant" seems more intuitive, IMHO.
• Second, how are we supposed to model duplicate pages that aren't due to different scripts or language variants? For example, ja:多項式函数 (初等数学) vs ja:多項式函数 (the former is kind of a simplified version of the latter).

Waldyrious (talk) 19:44, 5 February 2023 (UTC)[reply]