Property talk:P2354

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Documentation

[create Create a translatable help page (preferably in English) for this property to be included here]
Value type “Wikimedia list article (Q13406463): This property should use items as value that contain property “instance of (P31)”. On these, the value for instance of (P31) should be an item that uses subclass of (P279) with value Wikimedia list article (Q13406463) (or a subclass thereof). (Help)
Exceptions are possible as rare values may exist.
List of this constraint violations: Database reports/Constraint violations/P2354#Value type Q13406463, SPARQL, SPARQL (new)
Property “is a list of (P360)” declared by target items of “has list (P2354): If [item A] has this property with value [item B], [item B] is required to have property “is a list of (P360)”. (Help)
Exceptions are possible as rare values may exist.
List of this constraint violations: Database reports/Constraint violations/P2354#Target required claim P360, SPARQL, SPARQL (by value), SPARQL (new)
Distinct values: this property likely contains a value that is different from all other items. (Help)
Exceptions are possible as rare values may exist.
List of this constraint violations: Database reports/Constraint violations/P2354#Unique value, SPARQL (every item), SPARQL (by value), SPARQL (new)

Constraints[edit]

Hi @Andreasmperu: many thanks for creating this. The constraints may need a bit more thinking about though.

If we take the original use-case as an example,

then in general:

These constraints should therefore all probably be dropped, unless a way can be found to suitably qualify them. Jheald (talk) 23:27, 25 November 2015 (UTC)

The initial sample might not be ideal. Q2074737 could be a better sample.
As for the constraints, let's just avoid making them mandatory.
Given the various ways is a list of (P360) is being used, maybe named after (P138) could work better. --- Jura 08:48, 26 November 2015 (UTC)
@Jura1: Maybe. But another thing: why have you made P31 mandatory? I would have thought, if anything, lists would be more likely to be created for classes. (Except for cases, like Spain, where we're using this for lists related to a thing). Jheald (talk) 09:12, 26 November 2015 (UTC)
In theory I guess that's true. In any case, I will remove "mandatory=true". --- Jura 09:19, 26 November 2015 (UTC)
I added both. Somehow I think this property might have been defined too large. Should Q29 include all lists related to Spain? --- Jura 09:29, 26 November 2015 (UTC)
@Jura1: No. The purpose is to allow Q29 to include some lists related to Spain. Jheald (talk) 11:23, 26 November 2015 (UTC)

Using inverse constraint (Q21510855)[edit]

Due to contribution the User:Xaris333 request me to explain the statement property constraint (P2302) inverse constraint (Q21510855) / property (P2306) is a list of (P360):

by Wikidata property example (P1855) would mean this:

and that would mean:

conversely, it also makes no sense:

it is correct

Thus, a inverse constraint is not given and therefore should not be inserted. --Labant (talk) 02:09, 1 January 2019 (UTC)