View source for Talk:Q25796498

How is it planned to support? What does it mean exactly? That dates (of creation/demolition, birth/death, and so on) should exist or if they exist they should coordinate? --[[User:Infovarius|Infovarius]] ([[User talk:Infovarius|<span class="signature-talk">{{int:Talkpagelinktext}}</span>]]) 10:25, 16 August 2017 (UTC)
:Its implementation is pending (and near), I talked with [[User:Lucas Werkmeister (WMDE)|Lucas Werkmeister]] about it. You can see some details in [[phab:T141859|T141859]]. Indeed, there should be no violation if those statements aren't defined. Thanks for your interest! --<span style="font-size:95%;">[[User:Abián|abi]][[User talk:Abián|án]]</span> 11:56, 16 August 2017 (UTC)

== Removed from properties ==
As this breaks the constraint reports, I removed this from the 57 properties listed on https://www.wikidata.org/w/index.php?&oldid=609831868 . They can easily be re-added once support is available. <br/>--- [[User talk:Jura1|Jura]] 11:07, 16 December 2017 (UTC)
: How does (did) it break the constraint reports? WikibaseQualityConstraints / ''checkConstraints'' shouldn’t have any problems with this, and I really don’t like the thought of removing constraints just because one of the systems checking them is broken (for instance, I also oppose [[Special:Diff/581656639]], even though that one’s arguably my fault because [[phabricator:T178295]] is still awaiting a fix). --[[User:Lucas Werkmeister (WMDE)|Lucas Werkmeister (WMDE)]] ([[User talk:Lucas Werkmeister (WMDE)|<span class="signature-talk">{{int:Talkpagelinktext}}</span>]]) 13:08, 18 December 2017 (UTC)

::All constraint reports with this constraint hadn't been updated in four months. <br/>--- [[User talk:Jura1|Jura]] 13:54, 20 December 2017 (UTC)
::I wasn't aware it worked with your gadget .. did it? <br/>--- [[User talk:Jura1|Jura]] 13:59, 20 December 2017 (UTC)
::: Sorry, I didn’t see your reply earlier – by constraint reports, I assume you mean [[Wikidata:Database reports/Constraint violations]], generated by {{U'|KrBot}}? For ''checkConstraints'' it should work, yes, you’d only see a <q>{{int:wbqc-constraintreport-status-todo}}</q> status on [[Special:ConstraintReport]], and nothing in the gadget. (I tested it just now with {{Q|Q179}}, since {{P|P176}} right now does have the constraint statement.) --[[User:Lucas Werkmeister (WMDE)|Lucas Werkmeister (WMDE)]] ([[User talk:Lucas Werkmeister (WMDE)|<span class="signature-talk">{{int:Talkpagelinktext}}</span>]]) 14:52, 4 January 2018 (UTC)
::::[[User:Lucas Werkmeister (WMDE)|Lucas Werkmeister (WMDE)]]: to summarize: the addition of the constraint already questioned in August still doesn't do anything for the gadget/[[Special:ConstraintReport]] (other than "todo"), but breaks the original constraint reports: https://www.wikidata.org/w/index.php?&oldid=609831868  Furthermore, the constraint is thought to be insufficiently specified to enable development. Is this correct? Why is WMDE insisting on the addition of these constraints? <br/>--- [[User talk:Jura1|Jura]] 16:05, 4 January 2018 (UTC)
:::::* I don’t see where the addition of the constraint was questioned – if you’re referring to Infovarius’ comment above, then that is not how I would interpret it. {{Tl|Constraint:Contemporary}} has also existed since well before August 2017, and I was under the impression that KrBot used to support it, too (but I might be wrong here).
:::::* A detailed specification of the constraint can be found in [[phabricator:T141859]]. It’s still open for discussion, but that doesn’t prevent it from being developed.
:::::* WMDE is not insisting on any such thing. As the maintainer of one of the two constraint-checking systems on Wikidata (that I’m aware of), I asked for clarification of your claim that {{tq|this breaks the constraint reports}} (in case you’d found a bug in WikibaseQualityConstraints), and then expressed my personal opinion on removing constraints due to implementation problems. Perhaps I should have marked that last part more clearly as nothing more than my opinion, but my primary reason for responding was just to check whether you had found a bug that I needed to fix :) --[[User:Lucas Werkmeister (WMDE)|Lucas Werkmeister (WMDE)]] ([[User talk:Lucas Werkmeister (WMDE)|<span class="signature-talk">{{int:Talkpagelinktext}}</span>]]) 11:29, 5 January 2018 (UTC)

:As Jura seems to insist that Lucas isn't "allowed" to comment, and that he thus has no opposition here, let me restate the opposition that I already expressed clearly in edit summaries. I oppose these removals per Lucas. Jura has not demonstrated to anyone's satisfaction that these removals are necessary or a good idea, and in the explicit absence of consensus, he needs to wait for a consensus for form, by more editors weighing in, before he changes the status quo. [[User:Swpb|Swpb]] ([[User talk:Swpb|<span class="signature-talk">{{int:Talkpagelinktext}}</span>]]) 14:28, 4 January 2018 (UTC)
::Other than that you oppose for the sake of opposing, maybe you can explain what the advantage of adding these statements is compared to a broken constraint reports. See [[#Contemporaneousness]] for a better aproach.
::Above these constraints was questioned in August already (by [[User:Infovarius]]) and I don't think [[User:Lucas Werkmeister (WMDE)]] is ready to implement it.
::As you don't seem to understand the editorial role of WMDE, I asked [[User:Lydia Pintscher (WMDE)]] to confirm it to you. <br/>--- [[User talk:Jura1|Jura]] 14:36, 4 January 2018 (UTC)
:::"oppose for the sake of opposing" is both false and intentionally inflammatory. Whether Lucas is allowed to "vote" or not, his logic, which I reiterate, is sound: "I really don’t like the thought of removing constraints just because one of the systems checking them is broken". Well, neither do I - there's no good reason for it. That's all the reason I or anyone should need to oppose this, and your dismissal of it doesn't strike it from the discussion. [[User:Swpb|Swpb]] ([[User talk:Swpb|<span class="signature-talk">{{int:Talkpagelinktext}}</span>]]) 14:43, 4 January 2018 (UTC)
::::I added a complex constraint to {{P|176}}. I could also add that to the other 56 properties. Would it then be okay for you to remove it from {{P|2302}} until the constraint is implemented in [[Special:ConstraintReport]] and the gadget? --[[User:Pasleim|Pasleim]] ([[User talk:Pasleim|<span class="signature-talk">{{int:Talkpagelinktext}}</span>]]) 20:02, 4 January 2018 (UTC)
:::::Yes, that seems totally reasonable. Thanks for coming though with a solution! [[User:Swpb|Swpb]] ([[User talk:Swpb|<span class="signature-talk">{{int:Talkpagelinktext}}</span>]]) 20:06, 4 January 2018 (UTC)

== Contemporaneousness == 

Until it's available, maybe we could add statement to the properties indicating the item using the property and the values used by the properties should be contemporary in one way or the other. {{P|1552}} could be used to state that. Depending on how it's measured, we could use different values, e.g. by the lifespan of two people. Such item can also help design a future constraint. <br/>--- [[User talk:Jura1|Jura]] 11:13, 16 December 2017 (UTC)

== Status future plans? ==

{{Strong_support}} I strongly support doing this as we have so many discussions in sv:Wikipedia when we have Wikidata driven templates that the name used is not the name used at that time.... this constraint will help a lot....

FYI:  I added the constraint to {{P|778}} and then the [[Wikidata:Database_reports/Constraint_violations/P778]] failed
 ERROR: Unknown constraint type: Q25796498.

OT: we are cleaning the Swedish church parishes in WD in project [https://phabricator.wikimedia.org/tag/wmse-riksarkivet-tora wmse-riksarkivet-tora] task [https://phabricator.wikimedia.org/T199784 T199784] and I guess the implementation of this constraint will impact how we model name changes etc. 
- [[User:Salgo60|Salgo60]] ([[User talk:Salgo60|<span class="signature-talk">{{int:Talkpagelinktext}}</span>]]) 07:10, 11 August 2018 (UTC)
:Hi, [[User:Salgo60|Salgo60]], thanks for your support! I'm currently implementing this constraint for [[Special:ConstraintReport]] and for the warnings on the entity pages, although [[phab:T195226|T195226]] will be resolved first. The constraint should be ready in September, that is, next month. :D --<span style="font-size:95%;">[[User:Abián|abi]][[User talk:Abián|án]]</span> 08:21, 11 August 2018 (UTC)
::{{u|Abián}} Thanks for fast answer... we are modelling about 3500 church parishes see [http://salgo60.github.io/Svenskaforsamlingar work area] and all input you have please let us know. I asked a question at [[d:Wikidata:Project_chat#Design_advice_for_church_parish_start_and_end_and_name_changes|Wikidata:Project_chat]] for feedback - [[User:Salgo60|Salgo60]] ([[User talk:Salgo60|<span class="signature-talk">{{int:Talkpagelinktext}}</span>]]) 08:37, 11 August 2018 (UTC)

== constraint check bug ==

It currently compares the last date of end of validity of one item to the first date of validty of another item.

However an item A may have multiple properties specifying one value declared until end date just before another value declared starting on a next day.

In that case we cannot attach item C to item A and specify also similar (but not necessarily the same) couple of dates to declare distinct values, one of these values only being item A, the other being item B declaring other distinct dates of validity.

  item A:     ...--------------------+                          (end date only)
  item B:                             +--------------------...  (start date only)

Try to declare:
  item C:                  +-------------------+

this currently conflicts in:
                           ^---------^                          (wrong start selected)
                                      ^---------^               (wrong end selected)
and this should just check:
              ^...-----------------------------^                (OK)
                           ^------------------------------...^  (OK)

The implementation forgets that not all properties are bounding their dates of validty on both start and end (the other bound is unspecified and just means "anything before", or "anything after"), and that the presence of multiple dates in a referenced item does not mean they are bound to the same declared property of that referenced object.

[[User:Verdy p|Verdy p]] ([[User talk:Verdy p|<span class="signature-talk">{{int:Talkpagelinktext}}</span>]]) 02:01, 5 October 2018 (UTC)
:Hi, [[User:Verdy p|Verdy p]]. I'm not sure I understand what you expose. Could you please provide an example using specific Wikidata entities and properties? Maybe you're just dealing with [[phab:T168379|this bug]] concerning precision. Or you've found something else? Anyway, please let me know. Thanks! --<span style="font-size:95%;">[[User:Abián|abi]][[User talk:Abián|án]]</span> 13:59, 5 October 2018 (UTC)
:*I added a bunch of tests to https://www.wikidata.org/w/index.php?title=Q15397819&oldid=757290166 + https://www.wikidata.org/w/index.php?title=Q4115189&oldid=757531389 and found it fairly reliable. Good work! Finally we can tackle all the anachronisms. --- [[User talk:Jura1|Jura]] 14:07, 5 October 2018 (UTC)

== Different precision ==

This constraint should not trigger for dates with different precision where match is possible. E.g. if person A has date of death of 1850, and person B, son of A, has birth date of July 5, 1850 - this is not wrong since A may have died in August or December. [[User:Laboramus|Laboramus]] ([[User talk:Laboramus|<span class="signature-talk">{{int:Talkpagelinktext}}</span>]]) 08:18, 20 October 2018 (UTC)
:This is due to [[phab:T168379|T168379]]. --<span style="font-size:95%;">[[User:Abián|abi]][[User talk:Abián|án]]</span> 22:39, 20 October 2018 (UTC)
:Also, if A is the mother, she could have died at childbirth. If A is the father, he could even have died nine months before, in 1849. -[[User:Ash Crow|Ash Crow]] ([[User talk:Ash Crow|<span class="signature-talk">{{int:Talkpagelinktext}}</span>]]) 05:24, 10 February 2019 (UTC)
::You're right! {{P|P25}} and {{P|P22}} aren't [[Help:Property constraints portal/Contemporary|contemporary properties]]. You can see a list of truly contemporary properties on [[:File:Restricción de coetaneidad - Trabajo Fin de Grado - David Abián.pdf]], pages [https://commons.wikimedia.org/w/index.php?title=File:Restricci%C3%B3n_de_coetaneidad_-_Trabajo_Fin_de_Grado_-_David_Abi%C3%A1n.pdf&page=59 51], [https://commons.wikimedia.org/w/index.php?title=File:Restricci%C3%B3n_de_coetaneidad_-_Trabajo_Fin_de_Grado_-_David_Abi%C3%A1n.pdf&page=60 52], [https://commons.wikimedia.org/w/index.php?title=File:Restricci%C3%B3n_de_coetaneidad_-_Trabajo_Fin_de_Grado_-_David_Abi%C3%A1n.pdf&page=61 53] and [https://commons.wikimedia.org/w/index.php?title=File:Restricci%C3%B3n_de_coetaneidad_-_Trabajo_Fin_de_Grado_-_David_Abi%C3%A1n.pdf&page=62 54]. However, sometimes editors want to have the constraint added to other properties to detect wrong data in most cases, although not all. In none of these cases the constraint should be added as a {{Q|Q21502408}}. --<span style="font-size:95%;">[[User:Abián|abi]][[User talk:Abián|án]]</span> 11:49, 10 February 2019 (UTC)
:Still a problem 5 years later where Nelson is flagged as an invalid participant at the {{Q|171416}}. The battle and his death date are to the same precision, but it merely reports the year being 1805 being incompatible with a battle on the 21 Oct 1805 [[User:Vicarage|Vicarage]] ([[User talk:Vicarage|<span class="signature-talk">{{int:Talkpagelinktext}}</span>]]) 22:25, 25 May 2023 (UTC)