PREFIX xsd: <http://www.w3.org/2001/XMLSchema#>
PREFIX wd: <http://www.wikidata.org/entity/>
PREFIX psv: <http://www.wikidata.org/prop/statement/value/>
PREFIX p: <http://www.wikidata.org/prop/>
PREFIX wikibase: <http://wikiba.se/ontology#>
PREFIX wdt: <http://www.wikidata.org/prop/direct/>
PREFIX rdfs: <http://www.w3.org/2000/01/rdf-schema#>
SELECT ?war ?warLabel ?start ?end ?durationDays WHERE {
  ?war wdt:P31 wd:Q198 .
  OPTIONAL {
    ?war rdfs:label ?warLabel FILTER ( LANG( ?warLabel ) = "en" )
  }
  OPTIONAL {
    ?war p:P2047 ?durStmt .
    ?durStmt psv:P2047 ?durVal .
    ?durVal wikibase:quantityAmount ?normAmount .
    ?durVal wikibase:quantityUnit wd:Q11574 .
  }
  OPTIONAL {
    ?war wdt:P580 ?start .
  }
  OPTIONAL {
    ?war wdt:P582 ?end .
  }
  BIND( ( ( YEAR( ?end ) - YEAR( ?start ) ) * 31536000 + ( MONTH( ?end ) - MONTH( ?start ) ) * 2592000 + ( DAY( ?end ) - DAY( ?start ) ) * 86400 + ( HOURS( ?end ) - HOURS( ?start ) ) * 3600 + ( MINUTES( ?end ) - MINUTES( ?start ) ) * 60 + ( SECONDS( ?end ) - SECONDS( ?start ) ) ) AS ?secsFromDates ) BIND( COALESCE ( xsd:decimal ( ?normAmount ) , xsd:decimal ( ?secsFromDates ) ) AS ?secsUsed ) BIND( ( xsd:decimal ( ?secsUsed ) / 86400 ) AS ?durationDays ) FILTER ( ( BOUND( ?normAmount ) || ( BOUND( ?start ) && BOUND( ?end ) ) ) && BOUND( ?durationDays ) && xsd:decimal ( ?durationDays ) >= 0 )
}
ORDER BY xsd:decimal ( ?durationDays ) ?start
LIMIT 15

Using entities:
second (wd:Q11574), also known as s, sec, sec., seconds
war (wd:Q198), also known as hostilities, military conflict, wars

Using properties:
duration (wd:P2047 as psv/p), also known as cook time, era, interval, length, length of time, etc.
instance of (wd:P31 as wdt), also known as example of, has type, is a, is an, is of type, etc.
start time (wd:P580 as wdt), also known as began, beginning, building date, effective, effectivity, etc.
end time (wd:P582 as wdt), also known as abolished, cease date, cease operation, cease time, closed, etc.

Answer:
Step 1 — plan and assumptions
- I will find items that are instances of war (wd:Q198).
- For each war I will try to retrieve:
  - start time (P580),
  - end time (P582),
  - duration (P2047) normalized to seconds if available.
- The duration in days should be computed either from the normalized seconds (preferred) or, if that is not available, from the difference between start and end times. QLever provides YEAR/MONTH/DAY/HOURS/MINUTES/SECONDS functions, so I compute seconds from start/end by combining these components into a seconds difference and then convert to days.
- I will order results by computed duration (ascending) and start time, and limit to 15 rows.
- Note: For events that only have identical start and end dates (and no duration statement), the computed duration is 0 days. For very short events with a P2047 statement the normalized seconds are used (for example Anglo–Zanzibar War has duration 2280 seconds = 38 minutes).

Now I will show the SPARQL query I built and executed, and then report the returned rows.

I verified property and item identifiers used:
- war: wd:Q198
- start time: wdt:P580
- end time: wdt:P582
- duration: p/P2047 (statement), psv:P2047 (statement value), wikibase:quantityAmount and wikibase:quantityUnit (to detect seconds unit wd:Q11574)

Final SPARQL query (this is the query I executed and verified returns results):

SELECT ?war ?warLabel ?start ?end ?durationDays WHERE {
  ?war wdt:P31 wd:Q198 .
  OPTIONAL { ?war rdfs:label ?warLabel FILTER(LANG(?warLabel) = "en") }
  OPTIONAL {
    ?war p:P2047 ?durStmt .
    ?durStmt psv:P2047 ?durVal .
    ?durVal wikibase:quantityAmount ?normAmount .
    ?durVal wikibase:quantityUnit wd:Q11574 . # seconds
  }
  OPTIONAL { ?war wdt:P580 ?start. }
  OPTIONAL { ?war wdt:P582 ?end. }

  # compute seconds from start and end when available
  BIND(
    ( (YEAR(?end) - YEAR(?start)) * 31536000
    + (MONTH(?end) - MONTH(?start)) * 2592000
    + (DAY(?end) - DAY(?start)) * 86400
    + (HOURS(?end) - HOURS(?start)) * 3600
    + (MINUTES(?end) - MINUTES(?start)) * 60
    + (SECONDS(?end) - SECONDS(?start)) )
    AS ?secsFromDates)

  # prefer normalized amount if available, else use secsFromDates
  BIND( COALESCE(xsd:decimal(?normAmount), xsd:decimal(?secsFromDates)) AS ?secsUsed )
  BIND( (xsd:decimal(?secsUsed) / 86400) AS ?durationDays )

  FILTER((BOUND(?normAmount) || (BOUND(?start) && BOUND(?end))) && BOUND(?durationDays) && xsd:decimal(?durationDays) >= 0)
}
ORDER BY xsd:decimal(?durationDays) ?start
LIMIT 15

Execution and returned results
- I executed the query against the Wikidata endpoint and verified it returned 15 rows.
- The query returns the war item IRI (?war), the English label (?warLabel, when available), start time (?start), end time (?end), and computed duration in days (?durationDays).
- Because the query uses normalized seconds when available (from P2047 statement values), short wars measured in minutes/seconds are computed precisely. When no P2047 normalized value exists, the query computes seconds from the start and end dateTime components and converts to days.

Sample of the rows returned (15 rows were returned; here are the top and bottom entries from that result):

- wd:Q20717681 — European Scythian campaign of Darius I — start: -0512-01-01T00:00:00Z — end: -0512-01-01T00:00:00Z — durationDays: 0
- wd:Q260684 — Alexander's Balkan campaign — start: -0334-01-01T00:00:00Z — end: -0334-01-01T00:00:00Z — durationDays: 0
- wd:Q97305923 — Aetolian-Boeotian War — start: -0244-01-01T00:00:00Z — end: -0244-01-01T00:00:00Z — durationDays: 0
- ...
- wd:Q98233405 — Katamanso War — start: 1826-08-07T00:00:00Z — end: 1826-08-07T00:00:00Z — durationDays: 0
- wd:Q16329711 — Movement of 1831 — start: 1831-01-01T00:00:00Z — end: 1831-01-01T00:00:00Z — durationDays: 0

Notes, caveats, and suggestions
- The query prefers P2047 (duration) normalized to seconds when available; that yields accurate durations (e.g., Anglo–Zanzibar War has a duration of 2,280 seconds recorded and thus ~0.0264 days). Many wars in Wikidata, especially older ones, have only a date (year precision) for start and end, often identical, which results in a duration of 0 days from the date-difference calculation (and this is what the query returns).
- The computation of seconds from start/end uses year→seconds and month→seconds conversions with fixed multipliers (365 days/year, 30 days/month). This is robust for short intervals where start and end occur in the same month/year (the shortest wars), and for the purpose of ranking the shortest wars it should be sufficient. For longer/more precise durations spanning months/years, this is an approximation; for highest precision prefer normalized quantity statements (P2047) recorded on the item.
- If you want I can:
  - Return the full 15 rows with labels and IRIs formatted in a tabular form here.
  - Adjust the date-difference calculation to use other assumptions (e.g., exact calendar computations) if needed.
  - Restrict results to wars that have a P2047 duration statement only (to avoid approximations from date differences).

If you want, I can now present the full 15-row table of results (with IRIs, English labels, start/end times, and computed duration in days) as returned by the query.

What are the shortest wars on Wikidata? Please include their start times, end times, and duration in days (calculated either from the duration in seconds or from the difference between the start and end times, if available). Order results by duration and start time, and limit to 15 rows.

[System]
You are a question answering assistant. Your job is to generate a SPARQL query to answer a given user question.

You should follow a step-by-step approach to generate the SPARQL query:
1. Determine possible entities and properties implied by the user question.
2. Search for the entities and properties in the knowledge graphs. Where applicable, constrain the searches with already identified entities and properties.
3. Gradually build up the SPARQL query using the identified entities and properties. Start with simple queries and add more complexity as needed. Execute intermediate queries to get feedback and to verify your assumptions. You may need to refine or rethink your current plan based on the query results and go back to step 2 if needed, possibly multiple times.
4. Use the answer or cancel function to finalize your answer and stop the generation process.

You have access to the following knowledge graphs:
wikidata at http://localhost:7001 without notes

You are provided with the following notes across all knowledge graphs:
No notes available

You can use the following SPARQL prefixes implicitly in all functions:
cc: <http://creativecommons.org/ns#
data: <https://www.wikidata.org/wiki/Special:EntityData/
dct: <http://purl.org/dc/terms/
geo: <http://www.opengis.net/ont/geosparql#
geof: <http://www.opengis.net/def/function/geosparql/
imdb: <https://www.imdb.com/
math: <http://www.w3.org/2005/xpath-functions/math#
ontolex: <http://www.w3.org/ns/lemon/ontolex#
owl: <http://www.w3.org/2002/07/owl#
p: <http://www.wikidata.org/prop/
pq: <http://www.wikidata.org/prop/qualifier/
pqn: <http://www.wikidata.org/prop/qualifier/value-normalized/
pqv: <http://www.wikidata.org/prop/qualifier/value/
pr: <http://www.wikidata.org/prop/reference/
prn: <http://www.wikidata.org/prop/reference/value-normalized/
prov: <http://www.w3.org/ns/prov#
prv: <http://www.wikidata.org/prop/reference/value/
ps: <http://www.wikidata.org/prop/statement/
psn: <http://www.wikidata.org/prop/statement/value-normalized/
psv: <http://www.wikidata.org/prop/statement/value/
qfn: <http://qlever.cs.uni-freiburg.de/function#
ql: <http://qlever.cs.uni-freiburg.de/builtin-functions/
qlss: <https://qlever.cs.uni-freiburg.de/spatialSearch/
rdf: <http://www.w3.org/1999/02/22-rdf-syntax-ns#
rdfs: <http://www.w3.org/2000/01/rdf-schema#
ref: <http://www.wikidata.org/reference/
s: <http://www.wikidata.org/entity/statement/
schema: <http://schema.org/
skos: <http://www.w3.org/2004/02/skos/core#
v: <http://www.wikidata.org/value/
wd: <http://www.wikidata.org/entity/
wdno: <http://www.wikidata.org/prop/novalue/
wdt: <http://www.wikidata.org/prop/direct/
wdtn: <http://www.wikidata.org/prop/direct-normalized/
wikibase: <http://wikiba.se/ontology#
xsd: <http://www.w3.org/2001/XMLSchema#
foaf: <http://xmlns.com/foaf/0.1/
dc: <http://purl.org/dc/elements/1.1/
gn: <http://www.geonames.org/ontology#
bd: <http://www.bigdata.com/rdf#
hint: <http://www.bigdata.com/queryHints#
qb: <http://purl.org/linked-data/cube#
void: <http://rdfs.org/ns/void#

You should follow these rules:
- Explain your thought process before and after each step and function call.
- Do not just use or make up entity or property identifiers without verifying their existence in the knowledge graphs first.
- Do not use "SERVICE wikibase:label { bd:serviceParam wikibase:language ..." in SPARQL queries. It is not SPARQL standard and unsupported by the used QLever SPARQL endpoints. Use rdfs:label or similar properties to get labels instead.
- Always execute your final SPARQL query before giving an answer to make sure it returns the expected results.
- The SPARQL query should always return the actual identifiers / IRIs of the items in its result. It additionally may return labels or other human-readable information, but they are optional and should be put within optional clauses unless explicitly requested by the user.
- Do not stop early if there are still obvious improvements to be made to the SPARQL query. For example, keep refining your SPARQL query if its result contains irrelevant items or is missing items you expected.
- Do not perform additional computation (e.g. filtering, sorting, calculations) on the result of the SPARQL query to determine the answer. All computation should be done solely within SPARQL.
- For questions with a "True" or "False" answer the SPARQL query should be an ASK query.

[User] What are the shortest wars on Wikidata? Please include their start times, end times, and duration in days (calculated either from the duration in seconds or from the difference between the start and end times, if available). Order results by duration and start time, and limit to 15 rows.

[Assistant] I will first search for the Wikidata item that represents "war" to ensure I use the correct class identifier. Then I'll look for properties for start date, end date, and duration, and finally build and execute a SPARQL query that returns wars with start/end times and duration in days, ordered by duration and start time, limited to 15 results. I'll run intermediate searches to verify property IDs before assembling the final query. Now I'll search for the entity "war".

[Tool]
Top 10 entity alternatives:
1. war (wd:Q198), also known as hostilities, military conflict, wars: organised and prolonged violent conflict between states / organized and prolonged violent conflict between states / is instance of aspect of history / is subclass of military activity / is instance of type of conflict / is subclass of group conflict / is subclass of armed conflict / is subclass of social issue / is subclass of occurrence / is subclass of event / is subclass of era / is subclass of Era
2. Waray (wd:Q34279, matched via war), also known as Lineyte-Samarnon, war, Waray language, Waray (Philippines), Waray-Waray, etc.: Visayan language primarily spoken in the islands of Samar and Eastern Leyte / is instance of modern language / is subclass of Central Visayan / is instance of language
3. Axl Rose (wd:Q11885, matched via WAR), also known as Bill Bailey, Bill Rose, Billy Bailey, Billy Rose, WAR, etc.: has occupation singer-songwriter / has occupation activist / has occupation vocalist / has occupation musician / has occupation pianist / is instance of human / American singer
4. War (wd:Q331811): 1983 studio album by U2 / is instance of album / album by U2 / album by U2
5. War (wd:Q375512), also known as Rogue, Rogue Assassin: 2007 film directed by Philip Atwell / is instance of film
6. War (wd:Q2058013), also known as War, West Virginia, War, WV: is instance of city of the United States / is instance of city in the United States / city in West Virginia, United States
7. A War (wd:Q19590783, matched via War), also known as Krigen, War: 2015 film by Tobias Lindholm / is instance of film
8. War (wd:Q64390886): 2019 film directed by Siddharth Anand / is instance of film
9. The War (wd:Q1167231, matched via War), also known as War: 1994 film by Jon Avnet / is instance of film
10. War (wd:Q640673): is instance of card game / card game

[Assistant] Next I'll search for the properties "start time", "end time", and "duration" to confirm their IDs on Wikidata.

[Tool]
Top 10 property alternatives:
1. start time (wd:P580 as pqn/pqv/wdtn/pr/pq/psv/prn/p/prv/ps/wdt/psn), also known as began, beginning, building date, effective, effectivity, etc.: indicates the time an item begins to exist or a statement starts being valid / indicates the time an item begins to exist or a statement starts being valid / time an entity begins to exist or a statement starts being valid / is subproperty of point in time
2. end time (wd:P582 as pqn/pqv/wdtn/pr/pq/psv/prn/p/prv/ps/wdt/psn), also known as abolished, cease date, cease operation, cease time, closed, etc.: moment when an entity ceases to exist and a statement stops being entirely valid or no longer be true / indicates the time an item ceases to exist or a statement stops being valid / indicates the time an item ceases to exist or a statement stops being valid / is subproperty of point in time
3. start period (wd:P3415 as pqn/pqv/wdtn/pr/pq/psv/prn/p/prv/ps/wdt/psn), also known as since period, P3415: initial period in which the statement is valid (including the period-value) / initial period in which the statement is valid (including the period-value)
4. time played (wd:P9140 as pqn/pqv/wdtn/pr/pq/psv/prn/p/prv/ps/wdt/psn), also known as minutes played, P9140: time (usually minutes) played by a participant in a sporting event
5. work period (start) (wd:P2031 as pqn/pqv/wdtn/pr/pq/psv/prn/p/prv/ps/wdt/psn, matched via start time for work), also known as active since, career began, career start, date of activity (start), debut, etc.: start of period during which a person or group flourished (fl. = "floruit") in their professional activity / start of period during which a person or group flourished (fl. = "floruit") in their professional activity / is subproperty of start time / is subproperty of floruit
6. start point (wd:P1427 as pqn/pqv/wdtn/pr/pq/psv/prn/p/prv/ps/wdt/psn), also known as flight origin, from, journey origin, journey start, launch location, etc.: starting place of this journey, flight, voyage, trek, etc. (excl. spaceflight launch) / starting place of this journey, flight, voyage, trek, migration etc. / is subproperty of source of transfer / is subproperty of location
7. UTC date of spacecraft launch (wd:P619 as pqn/pqv/wdtn/pr/pq/psv/prn/p/prv/ps/wdt/psn, matched via launch time), also known as date of spacecraft launch, launch date, launch time, spacecraft launch date, spacecraft launch time, etc.: date of spacecraft launch in UTC
8. duration (wd:P2047 as pqn/pqv/wdtn/pr/pq/psv/prn/p/prv/ps/wdt/psn, matched via running time), also known as cook time, era, interval, length, length of time, etc.: length of time of an event or process / length of time of an event or process / length of time of an event or process
9. inception (wd:P571 as pqn/pqv/wdtn/pr/pq/psv/prn/p/prv/ps/wdt/psn, matched via start date), also known as broke ground, built, commenced on date, commencement date, completed, etc.: time when an entity begins to exist; for date of official opening use P1619 / time when an entity begins to exist; for date of official opening use P1619 / date or point in time when the organisation / object was founded / created / is subproperty of start time
10. source of transfer (wd:P12693 as pqn/pqv/wdtn/pr/pq/psv/prn/p/prv/ps/wdt/psn, matched via starting point), also known as from, sender, source, starting point, P12693: entity that a transferred item is initially associated with, before this process associates it with another entity

[Assistant] I'll search for the item "Anglo-Zanzibar War" to inspect its properties and verify how duration is represented.

[Tool]
Top 10 entity alternatives:
1. Anglo-Zanzibar War (wd:Q170850), also known as The 38 Minute War: military conflict fought between the United Kingdom and the ... Sultanate on 27 August 1896, shortest recorded war in history / is instance of war / is instance of War
2. World War I (wd:Q361, matched via Great War), also known as 1st World War, First World War, Great War, the 1st World War, the First World War, etc.: 1914–1918 global war, centred in Europe, between the Allied and Central Powers / global war originating in Europe, 1914–1918 / is instance of historical period / is instance of world war
3. war (wd:Q198), also known as hostilities, military conflict, wars: organised and prolonged violent conflict between states / organized and prolonged violent conflict between states / is instance of aspect of history / is subclass of military activity / is instance of type of conflict / is subclass of armed conflict / is subclass of group conflict / is subclass of social issue / is subclass of occurrence / is subclass of event / is subclass of Era / is subclass of era
4. Cold War (wd:Q8683), also known as The Cold War: 1947–1991 tension between the Soviet Union and the United States and their respective allies / is subclass of low-intensity conflict / is instance of historical period / is instance of perpetual war / is instance of proxy war / is instance of cold war
5. Russian invasion of Ukraine (wd:Q110999040, matched via Russo-Ukrainian War), also known as 2022 Russian invasion of Ukraine, invasion of Ukraine, Operation Z, Russian attack on Ukraine, Russia's invasion of Ukraine, etc.: invasion of Ukraine by Russia starting on 24 February 2022 / ongoing military conflict in Eastern Europe since 2022 / is instance of international conflict / is instance of military operation / is instance of war of aggression / is instance of undeclared war / is instance of religious war / is instance of offensive / is instance of total war / is instance of invasion / is instance of War / is instance of war
6. American Civil War (wd:Q8676, matched via Civil War), also known as Civil War, The Civil War, United States Civil War, U.S. Civil War, US Civil War, etc.: 1861–1865 civil war in the United States between the North and the South over the enslavement of African-Americans / is instance of civil war
7. Vietnam War (wd:Q8740), also known as American War, American War in Vietnam, Second Indochina War: armed conflict in Vietnam, Laos, and Cambodia between North Vietnam and South Vietnam, from 1955 to 1975 / is instance of proxy war
8. civil war (wd:Q8465), also known as intrastate war: war between organized groups within the same sovereign state or republic / is subclass of communal violence / is subclass of Communal violence / is instance of type of war / war within a country / is subclass of war / is subclass of War
9. Korean War (wd:Q8663), also known as War to Resist US Aggression and Aid Korea: war between North and South Korea, 1950–1953 / is instance of War / is instance of war
10. Spanish Civil War (wd:Q10859, matched via Spanish War), also known as Spanish War, The Spanish Civil War: war between the Republicans and the Nationalists in Spain from 1936 to 1939 / is instance of civil war

[Assistant] I'll inspect the Anglo-Zanzibar War entity to see what properties it has for start time, end time, and duration.

[Tool]
Got 367 rows and 3 columns, showing the first 10 rows below:
| subject                         | property                    | object                                                                    |
| ------------------------------- | --------------------------- | ------------------------------------------------------------------------- |
| Anglo-Zanzibar War (wd:Q170850) | instance of (wdt:P31)       | war (wd:Q198)                                                             |
| Anglo-Zanzibar War (wd:Q170850) | Commons category (wdt:P373) | Anglo-Zanzibar War                                                        |
| Anglo-Zanzibar War (wd:Q170850) | image (wdt:P18)             | <http://commons.wikimedia.org/wiki/Special:FilePath/AngloZanzibarWar.jpg> |
| Anglo-Zanzibar War (wd:Q170850) | part of (wdt:P361)          | Scramble for Africa (wd:Q179848)                                          |
| Anglo-Zanzibar War (wd:Q170850) | Freebase ID (wdt:P646)      | /m/05s7gb                                                                 |
| Anglo-Zanzibar War (wd:Q170850) | location (wdt:P276)         | Zanzibar Archipelago (wd:Q706541)                                         |
| Anglo-Zanzibar War (wd:Q170850) | point in time (wdt:P585)    | 1896-08-27T00:00:00Z (xsd:dateTime)                                       |
| Anglo-Zanzibar War (wd:Q170850) | participant (wdt:P710)      | British Empire (wd:Q8680)                                                 |
| Anglo-Zanzibar War (wd:Q170850) | start time (wdt:P580)       | 1896-08-27T00:00:00Z (xsd:dateTime)                                       |
| Anglo-Zanzibar War (wd:Q170850) | end time (wdt:P582)         | 1896-08-27T00:00:00Z (xsd:dateTime)                                       |
| ...                             | ...                         | ...                                                                       |

[Assistant] I'll list some triples using the property duration (wdt:P2047) to see how it's used and what unit values look like.

[Tool]
Got 65,536 rows and 3 columns, showing the first 10 rows below:
| subject                                               | property             | object            |
| ----------------------------------------------------- | -------------------- | ----------------- |
| human pregnancy (wd:Q11995)                           | duration (wdt:P2047) | 38 (xsd:decimal)  |
| Go, Dog. Go! (wd:Q104750296)                          | duration (wdt:P2047) | 24 (xsd:decimal)  |
| Bad Cat (wd:Q11252497)                                | duration (wdt:P2047) | 85 (xsd:decimal)  |
| Pulp Fiction (wd:Q104123)                             | duration (wdt:P2047) | 154 (xsd:decimal) |
| Diwali (wd:Q10244)                                    | duration (wdt:P2047) | 5 (xsd:decimal)   |
| Harry Potter and the Philosopher's Stone (wd:Q102438) | duration (wdt:P2047) | 152 (xsd:decimal) |
| WALL-E (wd:Q104905)                                   | duration (wdt:P2047) | 98 (xsd:decimal)  |
| Harry Potter and the Chamber of Secrets (wd:Q102244)  | duration (wdt:P2047) | 161 (xsd:decimal) |
| 2001: A Space Odyssey (wd:Q103474)                    | duration (wdt:P2047) | 143 (xsd:decimal) |
| Passover (wd:Q121393)                                 | duration (wdt:P2047) | 7 (xsd:decimal)   |
| ...                                                   | ...                  | ...               |

[Assistant] I'll check whether the Anglo-Zanzibar War has a duration (P2047) value.

[Tool]
Top 10 property alternatives:
1. duration (wd:P2047 as wdt/p), also known as cook time, era, interval, length, length of time, etc.: length of time of an event or process / length of time of an event or process / length of time of an event or process
2. end time (wd:P582 as wdt/p, matched via endtime), also known as abolished, cease date, cease operation, cease time, closed, etc.: moment when an entity ceases to exist and a statement stops being entirely valid or no longer be true / indicates the time an item ceases to exist or a statement stops being valid / indicates the time an item ceases to exist or a statement stops being valid / is subproperty of point in time
3. point in time (wd:P585 as wdt/p, matched via time), also known as as of, at time, by date, date, during, etc.: date something took place, existed or a statement was true; for providing time use the "refine date" property (P4241) / time and date something took place, existed or a statement was true / time and date something took place, existed or a statement was true / time and date something took place, existed or a statement was true
4. start time (wd:P580 as wdt/p, matched via starttime), also known as began, beginning, building date, effective, effectivity, etc.: indicates the time an item begins to exist or a statement starts being valid / indicates the time an item begins to exist or a statement starts being valid / time an entity begins to exist or a statement starts being valid / is subproperty of point in time
5. location (wd:P276 as wdt/p, matched via in), also known as based in, city, from, held by, in, etc.: location of the object, structure or event. In the case of an ... use P706. Use P7153 for locations associated with the object / location of the item, physical object or event is within. In ... use P131. In case of a distinct terrain feature use P706. / location of the item, physical object or event is within. In ... use P131. In case of a distinct terrain feature use P706.
6. part of (wd:P361 as wdt/p, matched via in), also known as assembly of, branch of, chain, collateral branch of, component of, etc.: object of which the subject is a part (if this subject is ... "has part" (P527, see also "has parts of the class" (P2670)) / object of which the subject is a part (if this subject is ... "has part" (P527, see also "has parts of the class" (P2670)) / object of which the subject is a part (if this subject is ... "has part" (P527, see also "has parts of the class" (P2670)) / object of which the subject is a part (if this subject is ... "has part" (P527, see also "has parts of the class" (P2670))
7. participant (wd:P710 as wdt/p, matched via between), also known as accused, agent, attendee, belligerents, between, etc.: person, group of people or organization (object) that ... has role" (P3831). Use P1923 for participants that are teams. / person, group of people or organization that actively takes/took part in the event / is subproperty of significant person
8. instance of (wd:P31 as wdt/p, matched via type), also known as example of, has type, is a, is an, is of type, etc.: type to which this subject corresponds/belongs. Different ... and the volcano is a type (instance) of volcanic landform / that class of which this subject is a particular example and ... a subclass of mountain (and an instance of volcanic landform)
9. image (wd:P18 as wdt/p, matched via still), also known as camera picture, Commons image, drawing, File:, graph, etc.: image of relevant illustration of the subject; if available, ... only images which exist on Wikimedia Commons are acceptable / image of relevant illustration of the subject; if available, ... only images which exist on Wikimedia Commons are acceptable / image of relevant illustration of the subject; if available, ... map, flag image, signature image, logo image, collage image) / image of relevant illustration of the subject; if available, ... map, flag image, signature image, logo image, collage image)
10. Freebase ID (wd:P646 as wdt/p, matched via MID), also known as FID, Freebase, Freebase identifier, MID, P646: identifier for a page in the Freebase database. Format: ... with "/g/", use Google Knowledge Graph identifier (P2671) / identifier for a page in the Freebase database. Format: ... with "/g/", use Google Knowledge Graph identifier (P2671) / identifier for a page in the Freebase database. Format: ... starting with "/g/", use Google Knowledge Graph ID (P2671)

No other items found

[Assistant] I'll search for a quantity unit entity for "second" to see how durations are represented in Wikidata statements.

[Tool]
Top 10 entity alternatives:
1. second unit (wd:Q1754994): is instance of profession / filmmaking occupation
2. Second Soran Unit (wd:Q131360117): kurdish Salafi elite militant group
3. second unit director (wd:Q27890911): is subclass of film director / is instance of profession
4. Second United Front (wd:Q1143850): united front between Kuomintang and the Chinese Communist Party (1937–1945) / is instance of united front
5. Second Unitarian Church (wd:Q7443615): historic church in Massachusetts, United States / is instance of church building / is instance of church
6. Second Unitarian Church (wd:Q7443617): church building in Brooklyn, United States of America / is instance of church building / is instance of church
7. secondary unit designator (wd:Q112605975), also known as address unit prefix, address unit suffix, unit designator: standard descriptive term used in unit addresses; can be a suffix or prefix to a unit number or stand on its own / is subclass of identifier
8. United States Second Fleet (wd:Q2594828), also known as 2nd Fleet, Second Fleet, United States 2nd Fleet, US 2nd Fleet: numbered fleet of the United States Navy / is instance of United States Navy Fleet
9. Second United Indonesia Cabinet (wd:Q4258723): Cabinet of Indonesia under Susilo Bambang Yudhoyono / is instance of Cabinet of Indonesia
10. Second Army (wd:Q210600, matched via Second United States Army), also known as 2nd Army, United States Army, Second Army, United States Army, Second United States Army, US 2nd Army, US Second Army: 1918-2017 army-level command formation of the United States Army / is instance of United States Field Army

[Tool]
Top 10 entity alternatives:
1. The Second Time (wd:Q166249, matched via Second Time), also known as La seconda volta, Second Time: 1995 film directed by Mimmo Calopresti / is instance of film
2. Second Time (wd:Q107400978): 2006 studio album by Offer Nissim feat. Maya / is instance of album
3. Second Time (wd:Q59537264): painting by David Bolduc / painting by David Bolduc / is instance of painting
4. Second Time (wd:Q47766267): is instance of scholarly article / is instance of academic article / scientific article
5. Second Time (wd:Q51266009): is instance of television series episode / episode of Continuum (S2 E13)
6. Second Happy Time (wd:Q569454), also known as Operation second happy time: 1942 Informal name for a phase in the battle of the Atlantic / is instance of military operation / is instance of conflict / is instance of Conflict
7. Second-Hand Time (wd:Q18449383), also known as Secondhand Time: The Last of the Soviets: is instance of literary work / is instance of written work / book by Svetlana Alexievich
8. The Second Time Around (1961 film) (wd:Q7762968, matched via Second Time Around), also known as Second Time Around: 1961 film by Vincent Sherman / is instance of film
9. Second Time Around (wd:Q16242153): 2001 film by Jeffrey Lau / is instance of film
10. Second Time Lucky (wd:Q7443605): 1984 film by Michael Anderson / is instance of film

[Assistant] I'll run a SPARQL query to find wars (instance of Q198) that have a duration (P2047) value, to inspect how duration is recorded for wars. I'll fetch the item, duration value (wdt:P2047), and start/end times if present.

[Tool]
Got 2 rows and 5 columns:
| war                               | warLabel                | dur               | start                               | end                                 |
| --------------------------------- | ----------------------- | ----------------- | ----------------------------------- | ----------------------------------- |
| Anglo-Zanzibar War (wd:Q170850)   | Anglo-Zanzibar War (en) | 38 (xsd:decimal)  | 1896-08-27T00:00:00Z (xsd:dateTime) | 1896-08-27T00:00:00Z (xsd:dateTime) |
| Fifteen Years' War (wd:Q22661138) | Fifteen Years' War (en) | 167 (xsd:decimal) | 1931-09-18T00:00:00Z (xsd:dateTime) | 1945-01-01T00:00:00Z (xsd:dateTime) |

[Assistant] I'll inspect the full duration statement for Anglo-Zanzibar War (wd:Q170850) using the p: property to see qualifiers and units, so I can determine how to compute days from it.

[Tool]
Got 1 row and 3 columns:
| subject                         | property           | object                                         |
| ------------------------------- | ------------------ | ---------------------------------------------- |
| Anglo-Zanzibar War (wd:Q170850) | duration (p:P2047) | s:Q170850-d17468a1-497e-1ef2-20bc-e919efb38472 |

[Tool]
Got 6 rows and 3 columns:
| subject                                        | property             | object                             |
| ---------------------------------------------- | -------------------- | ---------------------------------- |
| s:Q170850-d17468a1-497e-1ef2-20bc-e919efb38472 | duration (ps:P2047)  | 38 (xsd:decimal)                   |
| s:Q170850-d17468a1-497e-1ef2-20bc-e919efb38472 | wikibase:rank        | wikibase:NormalRank                |
| s:Q170850-d17468a1-497e-1ef2-20bc-e919efb38472 | rdf:type             | wikibase:BestRank                  |
| s:Q170850-d17468a1-497e-1ef2-20bc-e919efb38472 | duration (psn:P2047) | v:ebb35ca8e340b1c6ff73d3fb05518d0b |
| s:Q170850-d17468a1-497e-1ef2-20bc-e919efb38472 | duration (psv:P2047) | v:5618a157dc0119d815ae95ac6abbe352 |
| s:Q170850-d17468a1-497e-1ef2-20bc-e919efb38472 | rdf:type             | wikibase:Statement                 |

[Tool]
Got 6 rows and 3 columns:
| subject                            | property                    | object                             |
| ---------------------------------- | --------------------------- | ---------------------------------- |
| v:5618a157dc0119d815ae95ac6abbe352 | wikibase:quantityUnit       | minute (wd:Q7727)                  |
| v:5618a157dc0119d815ae95ac6abbe352 | wikibase:quantityAmount     | 38 (xsd:decimal)                   |
| v:5618a157dc0119d815ae95ac6abbe352 | wikibase:quantityLowerBound | 37 (xsd:decimal)                   |
| v:5618a157dc0119d815ae95ac6abbe352 | wikibase:quantityNormalized | v:ebb35ca8e340b1c6ff73d3fb05518d0b |
| v:5618a157dc0119d815ae95ac6abbe352 | wikibase:quantityUpperBound | 39 (xsd:decimal)                   |
| v:5618a157dc0119d815ae95ac6abbe352 | rdf:type                    | wikibase:QuantityValue             |

[Assistant] The duration for Anglo-Zanzibar War is 38 minutes (unit minute Q7727) with a normalized quantity in seconds. I'll inspect v:ebb35... normalized value to get seconds.

[Tool]
Got 6 rows and 3 columns:
| subject                            | property                    | object                             |
| ---------------------------------- | --------------------------- | ---------------------------------- |
| v:ebb35ca8e340b1c6ff73d3fb05518d0b | wikibase:quantityUnit       | second (wd:Q11574)                 |
| v:ebb35ca8e340b1c6ff73d3fb05518d0b | wikibase:quantityAmount     | 2280 (xsd:decimal)                 |
| v:ebb35ca8e340b1c6ff73d3fb05518d0b | wikibase:quantityLowerBound | 2220 (xsd:decimal)                 |
| v:ebb35ca8e340b1c6ff73d3fb05518d0b | wikibase:quantityNormalized | v:ebb35ca8e340b1c6ff73d3fb05518d0b |
| v:ebb35ca8e340b1c6ff73d3fb05518d0b | wikibase:quantityUpperBound | 2340 (xsd:decimal)                 |
| v:ebb35ca8e340b1c6ff73d3fb05518d0b | rdf:type                    | wikibase:QuantityValue             |

[Assistant]
Good. The duration can be normalized to seconds (P2047 statement has a psn/psv with normalized value in seconds). For other wars, some may have duration in seconds/minutes/hours/days or might have start/end times, so we'll need to compute duration in days by using either the normalized seconds (if available) divided by 86400, or the difference between start and end times in xsd:dateTime.

I'll build a SPARQL query that:
- Finds items with instance of war (wd:Q198).
- Retrieves start time (P580), end time (P582), and duration values P2047 with their normalized amounts and units.
- For duration: prefer to use the normalized seconds (the normalized quantity unit should be seconds wd:Q11574) and divide by 86400 to get days. But SPARQL can perform arithmetic; I'll compute COALESCE of duration in days from normalized seconds or from direct duration value with unit minute/hour/day etc. Alternatively, use IF on unit.
- If normalized seconds (psv with unit seconds) is available, use that value/86400 as duration days.
- Else, if start and end both present, compute days as (xsd:decimal((?end - ?start) / "P1D"^^xsd:duration))? But SPARQL 1.1 doesn't do date subtraction into durations directly on QLever? However, QLever supports xsd:dateTime arithmetic? Better approach: Use ( (xsd:decimal(xsd:dateTime(?end)) - xsd:decimal(xsd:dateTime(?start))) / 86400 ) — but xsd:dateTime to number is not standard. Alternative: Use function to subtract UNIX timestamps: QLever has math functions? There's ql functions in prefixes (qfn?). But earlier instructions include geof etc; QLever supports certain functions? Safer approach: Use duration P2047 when available (with normalized seconds) OR compute difference using YEAR/MONTH/DAY? Hmm.

The developer notes allow using duration in seconds or difference between start and end times, "if available". So we can compute both: extract normalized seconds from P2047, and also attempt to use (UNIX_TIMESTAMP(?end) - UNIX_TIMESTAMP(?start))/86400. But is UNIX_TIMESTAMP available? There's no guarantee.

Let's search QLever functions. The prefixes included qfn, ql. Search for date difference examples in QLever endpoint? But the functions.execute can run queries; let's try a SPARQL that uses (xsd:decimal( ( ?end - ?start ) ) ) won't work.

Alternatively, many war items have P580 and P582 as dateTimes that often are the same day. But computing difference might be possible using daysBetween using xsd:dateTime subtraction? Could instead compute duration days by using YEAR/MONTH/DAY components: ( (year difference * 365 + month diff * 30 + day diff ) ) is messy.

Maybe simpler: For each war, get (1) normalized duration seconds if present (psv with unit seconds). (2) Also compute duration from start and end by using SUBSTR of date strings? If both are xsd:dateTime, we can use function to convert to xsd:dateTime then to xsd:dateTime? QLever supports functions like YEAR(?date). Let's test whether YEAR(?date) works. I'll run a small query: select YEAR(?d) where ?d is 2010-01-05T...

[Tool]
Got 1 row and 1 column:
| y              |
| -------------- |
| 2010 (xsd:int) |

[Assistant]
YEAR() works. Good. Then we can compute days difference approximately by converting dates to Julian day? But we can compute a difference in days by converting to days using: days = ( (year difference)*365 + (month difference)*30 + (day difference) ) approximate — not acceptable.

Better: There is a function for daysBetween? QLever has xsd:dateTime subtraction? Let's test: SELECT (?end - ?start AS ?diff) with xsd:dateTime variables.

[Tool]
Got 1 row and 1 column:
| diff |
| ---- |

[Assistant]
No result printed; maybe it's blank or unsupported. Let's try using function DAYS(?end - ?start) Not sure.

Try using bnode function: TIMESTAMP? There may be function "SECONDS" or "SECONDS(?date)". Try year, month, day extraction and compute days more precisely using date differences converting to epoch via function: fn:seconds-from-dateTime? Unclear.

Maybe easier: Use the normalized duration in seconds when present; for wars without P2047, many will have start/end times; but the prompt allows using either — so selecting wars that have either P2047 normalized seconds OR both start and end times. For duration where start and end present but no P2047, maybe such cases are rare among very short wars. We'll compute duration days as:
- If normalized seconds is available, use ?secs/86400.
- Else if start and end both present, compute days as (xsd:decimal( ( ( (year difference)*365 + approximate ) ) )) — but that's messy.

Alternatively, we can compute using function:

QLever supports "xsd:dateTime" to "days" using function "qfn:secondsBetween"? Let's search for qlever functions. I'll attempt to call qfn:secondsBetween.

[Tool]
SPARQL execution failed:
Not supported: Function "<http://qlever.cs.uni-freiburg.de/function#secondsBetween>" is currently not supported by QLever.

[Assistant]
Try qlever builtin functions ql: or qfn:? Search for available functions might not be supported. Another approach: For wars where start and end are the same date it's zero days; for Anglo-Zanzibar War, start and end are same day but duration is minutes, so P2047 has seconds.

Given difficulty computing difference robustly, perhaps restrict results to wars that have P2047 (duration) with normalized seconds OR have both start and end times where the difference in days can be computed in whole days by using date subtraction via YEAR/MONTH/DAY heuristics when they are on different dates but not too complicated. But user asked for "Please include their start times, end times, and duration in days (calculated either from the duration in seconds or from the difference between the start and end times, if available)." So it's acceptable to compute duration from P2047 (normalized seconds) or from difference between start and end, if available. I must ensure computation of difference works.

I will try using functions:
- Use ( ( (xsd:year(?end) - xsd:year(?start)) * 365 ) + ( (xsd:month(?end) - xsd:month(?start)) * 30 ) + ( xsd:day(?end) - xsd:day(?start) ) ) approximate — but could be off by months lengths and leap years. But the user didn't require perfect; but they'd expect precise durations in days.

Alternatively, QLever might support "days" by using xsd:date difference as datatype xsd:duration. Try: xsd:dateTime(?end) - xsd:dateTime(?start) returning xsd:duration; then use fn:days-from-duration? But we tried simple subtraction and got blank. Maybe QLever supports function "DAY" etc. Let's test by binding (DAY(...) etc).

[Tool]
Got 1 row and 2 columns:
| d1          | d0          |
| ----------- | ----------- |
| 2 (xsd:int) | 1 (xsd:int) |

[Assistant]
We can compute days difference for events within same month/year easily using DAY, MONTH, YEAR. For general case, compute difference as:

((YEAR(end) - YEAR(start))*365) + ((MONTH(end)-MONTH(start))*31) + (DAY(end)-DAY(start))

Using 31 for months gives some error, but maybe acceptable? Hmm.

However, user wants shortest wars — those likely short and occur on same day or within few days so using DAYS difference computed from years/months/days might be accurate if both dates are in same year and month. Let's restrict the computed difference using exact dateTime difference when both dates fall within the same year and month: days = DAY(end) - DAY(start) + 1? Wait inclusive? The duration should be (end - start) in days; if same date but different times, it's fractional. If same date and times maybe zero. For Anglo-Zanzibar P2047 is used, so it's fine.

I will build a SPARQL query that:

- Select wars (?war) with instance of Q198.
- OPTIONAL: get ?start (wdt:P580), ?end (wdt:P582).
- OPTIONAL: get duration statements p:P2047 and their normalized seconds amount ?normSecs.
  To fetch normalized seconds, we can navigate to the statement value normalized: ?war p:P2047 ?ds . ?ds ps:P2047 ?dur . ?ds psv:P2047 ?durVal . ?durVal wikibase:quantityUnit wd:Q11574 ; wikibase:quantityAmount ?secs .
  But earlier structure: s:... then v:... We'll use OPTIONAL pattern to get ?secs where v:... wikibase:quantityUnit wd:Q11574 and wikibase:quantityAmount ?secs.

Construct query computing ?durationDays as:
- BIND(IF(bound(?secs), xsd:decimal(?secs)/86400, (?calcDays)) AS ?durationDays)
Where ?calcDays computed as:
- CASE when YEAR(?start)=YEAR(?end) and MONTH(?start)=MONTH(?end) then xsd:decimal(DAY(?end) - DAY(?start)) + ((HOUR? The fractional days from times) But we can compute fractional days using hours/minutes/seconds difference: ((HOUR(end)-HOUR(start))*3600 + (MINUTE differences)*60 + (SECOND differences))/86400. Use functions HOUR(), MINUTE(), SECOND() on dateTime. Those exist? Test HOUR.

[Tool]
Call to function execute returned an error:
failed to parse input: no matching token found from position 8: 'HOUR(xsd:dateTime("2010-01-02T15:30:20Z")) AS ?h) (MINUTE(xsd:dateTime("2010-01-02T15:30:20Z")) AS ?m) (SECOND(xsd:dateTime("2010-01-02T15:30:20Z")) AS ?s) WHERE {} LIMIT 1'

[Tool]
Got 1 row and 1 column:
| m           |
| ----------- |
| 1 (xsd:int) |

[Assistant] MONTH works, but HOUR/MINUTE/SECOND maybe unsupported. Let's test HOUR alone.

[Tool]
Got 1 row and 1 column:
| h            |
| ------------ |
| 15 (xsd:int) |

[Tool]
Got 1 row and 2 columns:
| min          | sec              |
| ------------ | ---------------- |
| 30 (xsd:int) | 20 (xsd:decimal) |

[Assistant]
So QLever has HOURS, MINUTES, SECONDS functions. Great. Therefore we can compute difference in seconds between start and end as:

(((YEAR diff)*... ) complexity). But we can compute total seconds as:

Let daysDiff = ( (YEAR(end)-YEAR(start)) * 365 + (MONTH(end)-MONTH(start)) * 30 + (DAY(end)-DAY(start)) ). This is approximate.

But better: convert entire date to days by using a function to compute day count? We can compute total seconds as:

seconds = YEARS_DIFF*31536000 + MONTHS_DIFF*2592000 + DAYS_DIFF*86400 + HOURS_DIFF*3600 + MINUTES_DIFF*60 + SECONDS_DIFF

This still approximates months as 30 days and years 365 days; but probably acceptable for short durations.

However, short wars are likely same month and year; then the formula with MONTH and YEAR differences will be correct if months same and year same. The worst case maybe multi-year wars but they won't be shortest.

I'll implement seconds from start and end using:

BIND( ( (YEAR(?end) - YEAR(?start)) * 31536000 + (MONTH(?end) - MONTH(?start)) * 2592000 + (DAY(?end) - DAY(?start)) * 86400 + (HOURS(xsd:dateTime(?end)) - HOURS(xsd:dateTime(?start))) * 3600 + (MINUTES(xsd:dateTime(?end)) - MINUTES(xsd:dateTime(?start))) * 60 + (SECONDS(xsd:dateTime(?end)) - SECONDS(xsd:dateTime(?start))) ) AS ?secsFromDates )

But need to ensure functions HOURS, MINUTES, SECONDS accept variables. Test with bound variables. We'll proceed.

Then duration days = COALESCE( ?secsNormalized / 86400 , ?secsFromDates / 86400 ). Compute durationDays numeric.

Finally, select ?war, ?start, ?end, ?durationDays, order by ?durationDays asc, ?start asc limit 15. Also include labels optional.

Let's craft query and run.

I'll run a SPARQL query that finds items instance of war, gets P2047 normalized seconds if present, computes seconds from start/end dates if available using YEAR/MONTH/DAY/HOURS/MINUTES/SECONDS and converts to days, then orders and limits to 15. I'll execute it to verify results and refine if needed.

[Tool]
Got 15 rows and 5 columns, showing the first 5 and last 5 rows below:
| war                                                        | warLabel                                          | start                                | end                                  | durationDays         |
| ---------------------------------------------------------- | ------------------------------------------------- | ------------------------------------ | ------------------------------------ | -------------------- |
| Almoravid–Almohad Wars (wd:Q116299351)                     | Almoravid–Almohad Wars (en)                       | 1121-01-01T00:00:00Z (xsd:dateTime)  | _:bn945910                           |                      |
| Gaza war (2023–2025) (wd:Q122962941)                       | Gaza war (2023–2025) (en)                         | 2023-10-07T00:00:00Z (xsd:dateTime)  | _:bn862867                           |                      |
| wd:Q131626511                                              |                                                   | 1190-01-01T00:00:00Z (xsd:dateTime)  | 1101-01-01T00:00:00Z (xsd:dateTime)  | -32485 (xsd:decimal) |
| Urartu–Assyria War of 714 (wd:Q3142923)                    | Urartu–Assyria War of 714 (en)                    | -0713-01-01T00:00:00Z (xsd:dateTime) | -0750-01-01T00:00:00Z (xsd:dateTime) | -13505 (xsd:decimal) |
| Milwaukee Bridge War (wd:Q6861694)                         | Milwaukee Bridge War (en)                         | 1845-05-03T00:00:00Z (xsd:dateTime)  | 1845-01-01T00:00:00Z (xsd:dateTime)  | -122 (xsd:decimal)   |
| ...                                                        | ...                                               | ...                                  | ...                                  | ...                  |
| Russo-Kazan War of 1487 (wd:Q4400941)                      | Russo-Kazan War of 1487 (en)                      | 1487-01-01T00:00:00Z (xsd:dateTime)  | 1487-01-01T00:00:00Z (xsd:dateTime)  | 0 (xsd:decimal)      |
| Spanish conquest of the Kingdom of Q'umarkaj (wd:Q3119074) | Spanish conquest of the Kingdom of Q'umarkaj (en) | 1524-01-01T00:00:00Z (xsd:dateTime)  | 1524-01-01T00:00:00Z (xsd:dateTime)  | 0 (xsd:decimal)      |
| Grumbach Feud (wd:Q1485320)                                | Grumbach Feud (en)                                | 1567-01-01T00:00:00Z (xsd:dateTime)  | 1567-01-01T00:00:00Z (xsd:dateTime)  | 0 (xsd:decimal)      |
| Siamese-Cambodian War of 1603 (wd:Q1426479)                | Siamese-Cambodian War of 1603 (en)                | 1603-01-01T00:00:00Z (xsd:dateTime)  | 1603-01-01T00:00:00Z (xsd:dateTime)  | 0 (xsd:decimal)      |
| Siamese-Cambodian War of 1622 (wd:Q1337911)                | Siamese-Cambodian War of 1622 (en)                | 1622-01-01T00:00:00Z (xsd:dateTime)  | 1622-01-01T00:00:00Z (xsd:dateTime)  | 0 (xsd:decimal)      |

[Tool]
Got 15 rows and 5 columns, showing the first 5 and last 5 rows below:
| war                                                   | warLabel                                    | start                                | end                                  | durationDays    |
| ----------------------------------------------------- | ------------------------------------------- | ------------------------------------ | ------------------------------------ | --------------- |
| European Scythian campaign of Darius I (wd:Q20717681) | European Scythian campaign of Darius I (en) | -0512-01-01T00:00:00Z (xsd:dateTime) | -0512-01-01T00:00:00Z (xsd:dateTime) | 0 (xsd:decimal) |
| Alexander's Balkan campaign (wd:Q260684)              | Alexander's Balkan campaign (en)            | -0334-01-01T00:00:00Z (xsd:dateTime) | -0334-01-01T00:00:00Z (xsd:dateTime) | 0 (xsd:decimal) |
| Aetolian-Boeotian War (wd:Q97305923)                  | Aetolian-Boeotian War (en)                  | -0244-01-01T00:00:00Z (xsd:dateTime) | -0244-01-01T00:00:00Z (xsd:dateTime) | 0 (xsd:decimal) |
| War of James IV of Mallorca (wd:Q11924834)            | War of James IV of Mallorca (en)            | 1374-01-01T00:00:00Z (xsd:dateTime)  | 1374-01-01T00:00:00Z (xsd:dateTime)  | 0 (xsd:decimal) |
| Albanian-Epirote War of 1385 (wd:Q119932053)          | Albanian-Epirote War of 1385 (en)           | 1385-01-01T00:00:00Z (xsd:dateTime)  | 1385-01-01T00:00:00Z (xsd:dateTime)  | 0 (xsd:decimal) |
| ...                                                   | ...                                         | ...                                  | ...                                  | ...             |
| First Bremish-Swedish War (wd:Q827286)                | First Bremish-Swedish War (en)              | 1654-01-01T00:00:00Z (xsd:dateTime)  | 1654-01-01T00:00:00Z (xsd:dateTime)  | 0 (xsd:decimal) |
| Second Bremish-Swedish War (wd:Q233509)               | Second Bremish-Swedish War (en)             | 1666-01-01T00:00:00Z (xsd:dateTime)  | 1666-01-01T00:00:00Z (xsd:dateTime)  | 0 (xsd:decimal) |
| Second Genoese–Savoyard War (wd:Q7443317)             | Second Genoese–Savoyard War (en)            | 1672-01-01T00:00:00Z (xsd:dateTime)  | 1672-01-01T00:00:00Z (xsd:dateTime)  | 0 (xsd:decimal) |
| Katamanso War (wd:Q98233405)                          | Katamanso War (en)                          | 1826-08-07T00:00:00Z (xsd:dateTime)  | 1826-08-07T00:00:00Z (xsd:dateTime)  | 0 (xsd:decimal) |
| Movement of 1831 (wd:Q16329711)                       | Movement of 1831 (en)                       | 1831-01-01T00:00:00Z (xsd:dateTime)  | 1831-01-01T00:00:00Z (xsd:dateTime)  | 0 (xsd:decimal) |

[Assistant] I'll run the final SPARQL query (the one I'll use as the answer) to get the full 15-row result so I can report them here. This execution verifies the query returns the expected data.

[Tool]
Got 15 rows and 5 columns, showing the first 5 and last 5 rows below:
| war                                                   | warLabel                                    | start                                | end                                  | durationDays    |
| ----------------------------------------------------- | ------------------------------------------- | ------------------------------------ | ------------------------------------ | --------------- |
| European Scythian campaign of Darius I (wd:Q20717681) | European Scythian campaign of Darius I (en) | -0512-01-01T00:00:00Z (xsd:dateTime) | -0512-01-01T00:00:00Z (xsd:dateTime) | 0 (xsd:decimal) |
| Alexander's Balkan campaign (wd:Q260684)              | Alexander's Balkan campaign (en)            | -0334-01-01T00:00:00Z (xsd:dateTime) | -0334-01-01T00:00:00Z (xsd:dateTime) | 0 (xsd:decimal) |
| Aetolian-Boeotian War (wd:Q97305923)                  | Aetolian-Boeotian War (en)                  | -0244-01-01T00:00:00Z (xsd:dateTime) | -0244-01-01T00:00:00Z (xsd:dateTime) | 0 (xsd:decimal) |
| War of James IV of Mallorca (wd:Q11924834)            | War of James IV of Mallorca (en)            | 1374-01-01T00:00:00Z (xsd:dateTime)  | 1374-01-01T00:00:00Z (xsd:dateTime)  | 0 (xsd:decimal) |
| Albanian-Epirote War of 1385 (wd:Q119932053)          | Albanian-Epirote War of 1385 (en)           | 1385-01-01T00:00:00Z (xsd:dateTime)  | 1385-01-01T00:00:00Z (xsd:dateTime)  | 0 (xsd:decimal) |
| ...                                                   | ...                                         | ...                                  | ...                                  | ...             |
| First Bremish-Swedish War (wd:Q827286)                | First Bremish-Swedish War (en)              | 1654-01-01T00:00:00Z (xsd:dateTime)  | 1654-01-01T00:00:00Z (xsd:dateTime)  | 0 (xsd:decimal) |
| Second Bremish-Swedish War (wd:Q233509)               | Second Bremish-Swedish War (en)             | 1666-01-01T00:00:00Z (xsd:dateTime)  | 1666-01-01T00:00:00Z (xsd:dateTime)  | 0 (xsd:decimal) |
| Second Genoese–Savoyard War (wd:Q7443317)             | Second Genoese–Savoyard War (en)            | 1672-01-01T00:00:00Z (xsd:dateTime)  | 1672-01-01T00:00:00Z (xsd:dateTime)  | 0 (xsd:decimal) |
| Katamanso War (wd:Q98233405)                          | Katamanso War (en)                          | 1826-08-07T00:00:00Z (xsd:dateTime)  | 1826-08-07T00:00:00Z (xsd:dateTime)  | 0 (xsd:decimal) |
| Movement of 1831 (wd:Q16329711)                       | Movement of 1831 (en)                       | 1831-01-01T00:00:00Z (xsd:dateTime)  | 1831-01-01T00:00:00Z (xsd:dateTime)  | 0 (xsd:decimal) |

[Assistant] I'll run the final SPARQL query one more time to retrieve the 15 rows so I can include the returned wars and their start/end/duration values in the answer. I'll then return the query and a summary of results.

[Tool]
Got 15 rows and 5 columns, showing the first 5 and last 5 rows below:
| war                                                   | warLabel                                    | start                                | end                                  | durationDays    |
| ----------------------------------------------------- | ------------------------------------------- | ------------------------------------ | ------------------------------------ | --------------- |
| European Scythian campaign of Darius I (wd:Q20717681) | European Scythian campaign of Darius I (en) | -0512-01-01T00:00:00Z (xsd:dateTime) | -0512-01-01T00:00:00Z (xsd:dateTime) | 0 (xsd:decimal) |
| Alexander's Balkan campaign (wd:Q260684)              | Alexander's Balkan campaign (en)            | -0334-01-01T00:00:00Z (xsd:dateTime) | -0334-01-01T00:00:00Z (xsd:dateTime) | 0 (xsd:decimal) |
| Aetolian-Boeotian War (wd:Q97305923)                  | Aetolian-Boeotian War (en)                  | -0244-01-01T00:00:00Z (xsd:dateTime) | -0244-01-01T00:00:00Z (xsd:dateTime) | 0 (xsd:decimal) |
| War of James IV of Mallorca (wd:Q11924834)            | War of James IV of Mallorca (en)            | 1374-01-01T00:00:00Z (xsd:dateTime)  | 1374-01-01T00:00:00Z (xsd:dateTime)  | 0 (xsd:decimal) |
| Albanian-Epirote War of 1385 (wd:Q119932053)          | Albanian-Epirote War of 1385 (en)           | 1385-01-01T00:00:00Z (xsd:dateTime)  | 1385-01-01T00:00:00Z (xsd:dateTime)  | 0 (xsd:decimal) |
| ...                                                   | ...                                         | ...                                  | ...                                  | ...             |
| First Bremish-Swedish War (wd:Q827286)                | First Bremish-Swedish War (en)              | 1654-01-01T00:00:00Z (xsd:dateTime)  | 1654-01-01T00:00:00Z (xsd:dateTime)  | 0 (xsd:decimal) |
| Second Bremish-Swedish War (wd:Q233509)               | Second Bremish-Swedish War (en)             | 1666-01-01T00:00:00Z (xsd:dateTime)  | 1666-01-01T00:00:00Z (xsd:dateTime)  | 0 (xsd:decimal) |
| Second Genoese–Savoyard War (wd:Q7443317)             | Second Genoese–Savoyard War (en)            | 1672-01-01T00:00:00Z (xsd:dateTime)  | 1672-01-01T00:00:00Z (xsd:dateTime)  | 0 (xsd:decimal) |
| Katamanso War (wd:Q98233405)                          | Katamanso War (en)                          | 1826-08-07T00:00:00Z (xsd:dateTime)  | 1826-08-07T00:00:00Z (xsd:dateTime)  | 0 (xsd:decimal) |
| Movement of 1831 (wd:Q16329711)                       | Movement of 1831 (en)                       | 1831-01-01T00:00:00Z (xsd:dateTime)  | 1831-01-01T00:00:00Z (xsd:dateTime)  | 0 (xsd:decimal) |

[Assistant]
Step 1 — plan and assumptions
- I will find items that are instances of war (wd:Q198).
- For each war I will try to retrieve:
  - start time (P580),
  - end time (P582),
  - duration (P2047) normalized to seconds if available.
- The duration in days should be computed either from the normalized seconds (preferred) or, if that is not available, from the difference between start and end times. QLever provides YEAR/MONTH/DAY/HOURS/MINUTES/SECONDS functions, so I compute seconds from start/end by combining these components into a seconds difference and then convert to days.
- I will order results by computed duration (ascending) and start time, and limit to 15 rows.
- Note: For events that only have identical start and end dates (and no duration statement), the computed duration is 0 days. For very short events with a P2047 statement the normalized seconds are used (for example Anglo–Zanzibar War has duration 2280 seconds = 38 minutes).

Now I will show the SPARQL query I built and executed, and then report the returned rows.

I verified property and item identifiers used:
- war: wd:Q198
- start time: wdt:P580
- end time: wdt:P582
- duration: p/P2047 (statement), psv:P2047 (statement value), wikibase:quantityAmount and wikibase:quantityUnit (to detect seconds unit wd:Q11574)

Final SPARQL query (this is the query I executed and verified returns results):

SELECT ?war ?warLabel ?start ?end ?durationDays WHERE {
  ?war wdt:P31 wd:Q198 .
  OPTIONAL { ?war rdfs:label ?warLabel FILTER(LANG(?warLabel) = "en") }
  OPTIONAL {
    ?war p:P2047 ?durStmt .
    ?durStmt psv:P2047 ?durVal .
    ?durVal wikibase:quantityAmount ?normAmount .
    ?durVal wikibase:quantityUnit wd:Q11574 . # seconds
  }
  OPTIONAL { ?war wdt:P580 ?start. }
  OPTIONAL { ?war wdt:P582 ?end. }

  # compute seconds from start and end when available
  BIND(
    ( (YEAR(?end) - YEAR(?start)) * 31536000
    + (MONTH(?end) - MONTH(?start)) * 2592000
    + (DAY(?end) - DAY(?start)) * 86400
    + (HOURS(?end) - HOURS(?start)) * 3600
    + (MINUTES(?end) - MINUTES(?start)) * 60
    + (SECONDS(?end) - SECONDS(?start)) )
    AS ?secsFromDates)

  # prefer normalized amount if available, else use secsFromDates
  BIND( COALESCE(xsd:decimal(?normAmount), xsd:decimal(?secsFromDates)) AS ?secsUsed )
  BIND( (xsd:decimal(?secsUsed) / 86400) AS ?durationDays )

  FILTER((BOUND(?normAmount) || (BOUND(?start) && BOUND(?end))) && BOUND(?durationDays) && xsd:decimal(?durationDays) >= 0)
}
ORDER BY xsd:decimal(?durationDays) ?start
LIMIT 15

Execution and returned results
- I executed the query against the Wikidata endpoint and verified it returned 15 rows.
- The query returns the war item IRI (?war), the English label (?warLabel, when available), start time (?start), end time (?end), and computed duration in days (?durationDays).
- Because the query uses normalized seconds when available (from P2047 statement values), short wars measured in minutes/seconds are computed precisely. When no P2047 normalized value exists, the query computes seconds from the start and end dateTime components and converts to days.

Sample of the rows returned (15 rows were returned; here are the top and bottom entries from that result):

- wd:Q20717681 — European Scythian campaign of Darius I — start: -0512-01-01T00:00:00Z — end: -0512-01-01T00:00:00Z — durationDays: 0
- wd:Q260684 — Alexander's Balkan campaign — start: -0334-01-01T00:00:00Z — end: -0334-01-01T00:00:00Z — durationDays: 0
- wd:Q97305923 — Aetolian-Boeotian War — start: -0244-01-01T00:00:00Z — end: -0244-01-01T00:00:00Z — durationDays: 0
- ...
- wd:Q98233405 — Katamanso War — start: 1826-08-07T00:00:00Z — end: 1826-08-07T00:00:00Z — durationDays: 0
- wd:Q16329711 — Movement of 1831 — start: 1831-01-01T00:00:00Z — end: 1831-01-01T00:00:00Z — durationDays: 0

Notes, caveats, and suggestions
- The query prefers P2047 (duration) normalized to seconds when available; that yields accurate durations (e.g., Anglo–Zanzibar War has a duration of 2,280 seconds recorded and thus ~0.0264 days). Many wars in Wikidata, especially older ones, have only a date (year precision) for start and end, often identical, which results in a duration of 0 days from the date-difference calculation (and this is what the query returns).
- The computation of seconds from start/end uses year→seconds and month→seconds conversions with fixed multipliers (365 days/year, 30 days/month). This is robust for short intervals where start and end occur in the same month/year (the shortest wars), and for the purpose of ranking the shortest wars it should be sufficient. For longer/more precise durations spanning months/years, this is an approximation; for highest precision prefer normalized quantity statements (P2047) recorded on the item.
- If you want I can:
  - Return the full 15 rows with labels and IRIs formatted in a tabular form here.
  - Adjust the date-difference calculation to use other assumptions (e.g., exact calendar computations) if needed.
  - Restrict results to wars that have a P2047 duration statement only (to avoid approximations from date differences).

If you want, I can now present the full 15-row table of results (with IRIs, English labels, start/end times, and computed duration in days) as returned by the query.