PREFIX dbo: <http://dbpedia.org/ontology/>
PREFIX dbp: <http://dbpedia.org/property/>
PREFIX rdfs: <http://www.w3.org/2000/01/rdf-schema#>
PREFIX dbr: <http://dbpedia.org/resource/>
SELECT DISTINCT ?airport ?label WHERE {
  ?airport a dbo:Airport .
  {
    ?airport dbp:location ?loc .
    FILTER ( isLiteral( ?loc ) && CONTAINS( LCASE( STR( ?loc ) ) , "california" ) )
  } UNION {
    ?airport dbo:location ?loc2 .
    FILTER ( isLiteral( ?loc2 ) && CONTAINS( LCASE( STR( ?loc2 ) ) , "california" ) )
  } UNION {
    ?airport dbo:location dbr:California
  } UNION {
    ?airport dbp:location dbr:California
  } UNION {
    ?airport dbo:state ?state1 .
    FILTER ( isLiteral( ?state1 ) && CONTAINS( LCASE( STR( ?state1 ) ) , "california" ) )
  } UNION {
    ?airport dbp:state ?state2 .
    FILTER ( isLiteral( ?state2 ) && CONTAINS( LCASE( STR( ?state2 ) ) , "california" ) )
  } UNION {
    ?airport dbo:state dbr:California
  } UNION {
    ?airport dbp:state dbr:California
  }
  FILTER ( ! CONTAINS( STR( ?airport ) , "__" ) ) OPTIONAL {
    ?airport rdfs:label ?label .
    FILTER ( LANG( ?label ) = 'en' )
  }
}
ORDER BY ?label

Got 131 rows and 2 columns, showing the first 5 and last 5 rows below:
| airport                                                                                | label                                  |
| --------------------------------------------------------------------------------------------------- | -------------------------------------- |
| Alfonsina's Airstrip (<http://dbpedia.org/resource/Alfonsina's_Airstrip>)                           | Alfonsina's Airstrip (en)              |
| Alum Rock Airport (dbr:Alum_Rock_Airport)                                                           | Alum Rock Airport (en)                 |
| Amboy Airfield (dbr:Amboy_Airfield)                                                                 | Amboy Airfield (en)                    |
| Amedee Army Airfield (dbr:Amedee_Army_Airfield)                                                     | Amedee Army Airfield (en)              |
| Apple Valley Airport (California) (<http://dbpedia.org/resource/Apple_Valley_Airport_(California)>) | Apple Valley Airport (California) (en) |
| ...                                                                                | ...                                    |
| Watsonville Municipal Airport (dbr:Watsonville_Municipal_Airport)                                   | Watsonville Municipal Airport (en)     |
| Weaverville Airport (dbr:Weaverville_Airport)                                                       | Weaverville Airport (en)               |
| Weed Airport (dbr:Weed_Airport)                                                                     | Weed Airport (en)                      |
| Willits Municipal Airport (dbr:Willits_Municipal_Airport)                                           | Willits Municipal Airport (en)         |
| Woodlake Airport (dbr:Woodlake_Airport)                                                             | Woodlake Airport (en)                  |

This refined query retrieves airports in California, USA, by considering both string matches and direct links to the California resource for location and state properties, and filters out non-standard IRIs. Examples include Alfonsina's Airstrip, Alum Rock Airport, Amboy Airfield, Amedee Army Airfield, and Apple Valley Airport (California). The full list is available in the query result.

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

You have access to the following knowledge graphs:
dbpedia at https://qlever.cs.uni-freiburg.de/api/dbpedia

You can use the following SPARQL prefixes implicitly in all functions:
dbo: <http://dbpedia.org/ontology/
dbp: <http://dbpedia.org/property/
dbr: <http://dbpedia.org/resource/
dc: <http://purl.org/dc/terms/
foaf: <http://xmlns.com/foaf/0.1/
owl: <http://www.w3.org/2002/07/owl#
prov: <http://www.w3.org/ns/prov#
purl: <http://purl.org/linguistics/gold/
rdf: <http://www.w3.org/1999/02/22-rdf-syntax-ns#
rdfs: <http://www.w3.org/2000/01/rdf-schema#
schema: <http://schema.org/
skos: <http://www.w3.org/2004/02/skos/core#
xsd: <http://www.w3.org/2001/XMLSchema#
geo: <http://www.opengis.net/ont/geosparql#
geosparql: <http://www.opengis.net/ont/geosparql#
gn: <http://www.geonames.org/ontology#
bd: <http://www.bigdata.com/rdf#
hint: <http://www.bigdata.com/queryHints#
wikibase: <http://wikiba.se/ontology#
qb: <http://purl.org/linked-data/cube#
void: <http://rdfs.org/ns/void#

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. Use the functions to search for 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. Use the execute function to get feedback on intermediate queries. You can go back and forth between knowledge graph searches and SPARQL query executions to refine the query.
4. Use the answer or cancel function to finalize your answer and stop the generation process.

Additional rules:
1. Explain your thought process before and after each step and function call.
2. Do not assume or make up any entities or properties without verifying them with the knowledge graphs and functions.
3. 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.
4. 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.
5. 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.
6. For questions with a "True" or "False" answer the SPARQL query should be an ASK query.
7. 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.

[User] Which airports are located in California, USA?

[Assistant]
Let's break down the question:

1. We are looking for airports (entities of type airport).
2. These airports should be located in California, USA.

First, I will search for the entity representing "California" in DBpedia to use as a location filter.

[Tool]
Top 10 entity alternatives:
1. California, also known as The Golden State (dbr:California): California is a state in the Western United States. It is border...t is the most populous and the third-largest U.S. state by area.
2. California (<http://dbpedia.org/resource/Category:California>)
3. California, California (<http://dbpedia.org/resource/California,_California>)
4. Califórnia (<http://dbpedia.org/resource/Califórnia>)
5. California Clásico (<http://dbpedia.org/resource/California_Clásico>): The California Clasico is the name given to the soccer rivalry b... Earthquakes and the Galaxy combined to win four MLS Cup titles.
6. Oakland, California, also known as "Oaktown", "The Town" (<http://dbpedia.org/resource/Oakland,_California>): Oakland is the largest city and the county seat of Alameda Count...lifornia, and the 45th most populated city in the United States.
7. Bakersfield, California, also known as "Nashville West" (<http://dbpedia.org/resource/Bakersfield,_California>)
8. Riverside, California (<http://dbpedia.org/resource/Riverside,_California>)
9. Monterey, California, also known as California's "First" City, Language Capital of the World, (<http://dbpedia.org/resource/Monterey,_California>): Monterey (Spanish: Monterrey; Ohlone: Aacistak) is a city locate... library, publicly-funded school, printing-press, and newspaper.
10. Burbank, California (<http://dbpedia.org/resource/Burbank,_California>): Burbank is a city in the southeastern end of the San Fernando Va...tudios, as well as having the largest IKEA in the United States.

[Assistant]
The main entity for California is dbr:California. Next, I need to identify the class or type for airports in DBpedia, which is likely dbo:Airport, but I will verify this to be sure.

I will search for the entity "airport" to confirm the correct class/type.

[Tool]
Top 10 entity alternatives:
1. Airport (dbr:Airport): An airport is an aerodrome with extended facilities, mostly for ...utility buildings such as control towers, hangars and terminals.
2. AirPort (dbr:AirPort): AirPort is the name given to a series of products by Apple Inc. ....On April 26, 2018, Apple discontinued the AirPort product line.
3. airport (dbo:Airport)
4. Airport (dbp:airport)
5. Haifa Airport (dbr:Haifa_Airport): Haifa Airport (Hebrew: נְמַל הַתְּעוּפָה חֵיפָה, Namal HaTe'ufa...izing the airport are domestic operations to Eilat and Tel Aviv.
6. Ziguinchor Airport (dbr:Ziguinchor_Airport): Ziguinchor Airport (French: Aéroport de Ziguinchor) (IATA: ZIG, ...he Ziguinchor Region (also known as Basse Casamance) in Senegal.
7. Yuzhno-Sakhalinsk Airport (dbr:Yuzhno-Sakhalinsk_Airport): Yuzhno-Sakhalinsk Airport (Russian: Аэропорт Южно-Сахалинск, IAT...no-Sakhalinsk Airport is the largest airport in Sakhalin Oblast.
8. Beledweyne Airport (dbr:Beledweyne_Airport): Beledweyne Airport or Haaji-Duqow Ahmed Fiidow Airport (ICAO: HC...is in the countryside 2 kilometres (1 mi) northeast of the city.
9. Heathrow Airport (dbr:Heathrow_Airport): Heathrow Airport, originally called London Airport until 1966 an...ort facility is owned and operated by Heathrow Airport Holdings.
10. Frankfurt Airport (dbr:Frankfurt_Airport): Frankfurt Airport (IATA: FRA, ICAO: EDDF) (German: Flughafen Fra...sa CityLine and Lufthansa Cargo as well as Condor and AeroLogic.

[Assistant]
The correct class for airports in DBpedia is dbo:Airport. Now, I need to find the property that links an airport to its location, specifically to dbr:California.

I will search for properties related to "location" for airports.

[Tool]
No property items found

No other items found

[Assistant] It appears there is no direct "location" property for dbo:Airport. However, airports may be linked to their location via properties such as "city", "state", "region", or "located in". I will search for properties related to "state" for dbo:Airport to see if there is a direct link to California.

[Tool]
No property items found

No other items found

[Assistant] No direct "state" property is found for dbo:Airport. Airports might be linked to their location via "city", and cities are then linked to states. I will now search for properties related to "city" for dbo:Airport.

[Tool]
No property items found

No other items found

[Assistant] There are no direct "city" or "state" properties found for dbo:Airport. However, airports might be linked to their location using a more general property like "location", "located in", or "region". I will now search for properties related to "region" for dbo:Airport.

[Tool]
No property items found

No other items found

[Assistant]
Since no specific location-related properties are returned for dbo:Airport, I will try a broader approach by listing some properties of a specific airport in California (for example, Los Angeles International Airport) to see how its location is represented.

First, I will search for "Los Angeles International Airport" to get its DBpedia entity.

[Tool]
Top 10 entity alternatives:
1. Los Angeles International Airport (dbr:Los_Angeles_International_Airport): Los Angeles International Airport (IATA: LAX, ICAO: KLAX, FAA LI... El Segundo to the south and the city of Inglewood to the east.
2. Los Angeles International Airport (<http://dbpedia.org/resource/Category:Los_Angeles_International_Airport>)
3. Los Angeles (international airport) (<http://dbpedia.org/resource/Los_Angeles_(international_airport)>)
4. Los Angeles International (airport) (<http://dbpedia.org/resource/Los_Angeles_International_(airport)>)
5. Los Angeles International airport (dbr:Los_Angeles_International_airport)
6. Los Angeles International Airport shooting (dbr:Los_Angeles_International_Airport_shooting)
7. Los Angeles International Airport station (dbr:Los_Angeles_International_Airport_station)
8. 2002 Los Angeles International Airport shooting (dbr:2002_Los_Angeles_International_Airport_shooting): On Independence Day of the United States, July 4, 2002, a lone t...shot by an El Al security guard after also being wounded by him.
9. 2013 Los Angeles International Airport shooting (dbr:2013_Los_Angeles_International_Airport_shooting): On November 1, 2013, a shooting occurred at around 9:20 a.m. PDT...curity Administration officer and injuring several other people.
10. 1974 Los Angeles International Airport bombing (dbr:1974_Los_Angeles_International_Airport_bombing): The 1974 Los Angeles International Airport bombing occurred on A...gree murder for committing the bombing and an additional attack.

[Tool]
Got 309 rows and 3 columns, showing the first 10 rows below:
| subject                                                                   | property                                                            | object                                                                                |
| ------------------------------------------------------------------------- | ------------------------------------------------------------------- | --------------------------------------------------------------------------------------------------------- |
| Los Angeles International Airport (dbr:Los_Angeles_International_Airport) | has abstract (dbo:abstract)                                         | Bandar Udara Internasional Los A... 16 mil (27 km) dari pusat kota. (in)                                  |
| Los Angeles International Airport (dbr:Los_Angeles_International_Airport) | Wikipage page ID (dbo:wikiPageID)                                   | 18131 (xsd:int)                                                                                |
| Los Angeles International Airport (dbr:Los_Angeles_International_Airport) | Wikipage revision ID (dbo:wikiPageRevisionID)                       | 1124952750 (xsd:int)                                                                                |
| Los Angeles International Airport (dbr:Los_Angeles_International_Airport) | page length (characters) of wiki page (dbo:wikiPageLength)          | 166992 (xsd:int)                                                                                |
| Los Angeles International Airport (dbr:Los_Angeles_International_Airport) | Link from a Wikipage to an external page (dbo:wikiPageExternalLink) | <http://digital2.library.ucla.edu/viewItem.do%3Fark=21198/zz0002nb0h>                                     |
| Los Angeles International Airport (dbr:Los_Angeles_International_Airport) | name (dbp:name)                                                     | Los Angeles International Airport (en)                                                                    |
| Los Angeles International Airport (dbr:Los_Angeles_International_Airport) | title (dbp:title)                                                   | Articles related to Los Angeles International Airport (en)                                                |
| Los Angeles International Airport (dbr:Los_Angeles_International_Airport) | location (dbp:location)                                             | Westchester, Los Angeles, California, U.S. (en)                                                           |
| Los Angeles International Airport (dbr:Los_Angeles_International_Airport) | type (dbp:type)                                                     | Public (en)                                                                                |
| Los Angeles International Airport (dbr:Los_Angeles_International_Airport) | location (dbo:location)                                             | Westchester, Los Angeles, California (<http://dbpedia.org/resource/Westchester,_Los_Angeles,_California>) |
| ...                                                                       | ...                                                                 | ...                                                                                |

[Assistant]
From the properties of Los Angeles International Airport, I see that:

- dbp:location and dbo:location are used, with values like "Westchester, Los Angeles, California" or the entity dbr:Westchester,_Los_Angeles,_California.

This suggests that airports are linked to their locations via dbo:location or dbp:location, which may point to a city or neighborhood entity. To find airports in California, I can:

1. Find all airports (rdf:type dbo:Airport).
2. Check if their dbo:location or dbp:location is in California, or if the location entity is linked to dbr:California via dbo:state, dbo:isPartOf, or similar.

First, I will check how dbr:Westchester,_Los_Angeles,_California is linked to dbr:California.

[Tool] Constraint "dbr:Westchester,_Los_Angeles,_California" for subject position is not a valid IRI. IRIs can be given in prefixed form, like "wd:Q937", as URIs, like "http://www.wikidata.org/entity/Q937", or in full form, like "<http://www.wikidata.org/entity/Q937>".

[Tool]
Got 7 rows and 3 columns:
| subject                                                                                | property                                                   | object                                                                                |
| --------------------------------------------------------------------------------------------------------- | ---------------------------------------------------------- | ---------------------------------------------------------------------------------------- |
| Westchester, Los Angeles, California (<http://dbpedia.org/resource/Westchester,_Los_Angeles,_California>) | Wikipage page ID (dbo:wikiPageID)                          | 27230070 (xsd:int)                                                                       |
| Westchester, Los Angeles, California (<http://dbpedia.org/resource/Westchester,_Los_Angeles,_California>) | Wikipage revision ID (dbo:wikiPageRevisionID)              | 360176610 (xsd:int)                                                                      |
| Westchester, Los Angeles, California (<http://dbpedia.org/resource/Westchester,_Los_Angeles,_California>) | page length (characters) of wiki page (dbo:wikiPageLength) | 38 (xsd:int)                                                                             |
| Westchester, Los Angeles, California (<http://dbpedia.org/resource/Westchester,_Los_Angeles,_California>) | Wikipage redirect (dbo:wikiPageRedirects)                  | Westchester, Los Angeles (<http://dbpedia.org/resource/Westchester,_Los_Angeles>)        |
| Westchester, Los Angeles, California (<http://dbpedia.org/resource/Westchester,_Los_Angeles,_California>) | rdfs:label                                                 | Westchester, Los Angeles, California (en)                                                |
| Westchester, Los Angeles, California (<http://dbpedia.org/resource/Westchester,_Los_Angeles,_California>) | prov:wasDerivedFrom                                        | <http://en.wikipedia.org/wiki/Westchester,_Los_Angeles,_California?oldid=360176610&ns=0> |
| Westchester, Los Angeles, California (<http://dbpedia.org/resource/Westchester,_Los_Angeles,_California>) | foaf:isPrimaryTopicOf                                      | <http://en.wikipedia.org/wiki/Westchester,_Los_Angeles,_California>                      |

[Tool]
Got 102 rows and 3 columns, showing the first 10 rows below:
| subject                                                                           | property                                                            | object                                                                   |
| --------------------------------------------------------------------------------- | ------------------------------------------------------------------- | ------------------------------------------------------------------------ |
| Westchester, Los Angeles (<http://dbpedia.org/resource/Westchester,_Los_Angeles>) | has abstract (dbo:abstract)                                         | Westchester – dzielnica w zachod... Otis College of Art and Design. (pl) |
| Westchester, Los Angeles (<http://dbpedia.org/resource/Westchester,_Los_Angeles>) | Wikipage page ID (dbo:wikiPageID)                                   | 481156 (xsd:int)                                                         |
| Westchester, Los Angeles (<http://dbpedia.org/resource/Westchester,_Los_Angeles>) | Wikipage revision ID (dbo:wikiPageRevisionID)                       | 1112956221 (xsd:int)                                                     |
| Westchester, Los Angeles (<http://dbpedia.org/resource/Westchester,_Los_Angeles>) | page length (characters) of wiki page (dbo:wikiPageLength)          | 30587 (xsd:int)                                                          |
| Westchester, Los Angeles (<http://dbpedia.org/resource/Westchester,_Los_Angeles>) | Link from a Wikipage to an external page (dbo:wikiPageExternalLink) | <http://www.ncwpdr.org/>                                                 |
| Westchester, Los Angeles (<http://dbpedia.org/resource/Westchester,_Los_Angeles>) | name (dbp:name)                                                     | Westchester (en)                                                         |
| Westchester, Los Angeles (<http://dbpedia.org/resource/Westchester,_Los_Angeles>) | type (dbo:type)                                                     | Neighborhoods of Los Angeles (dbr:Neighborhoods_of_Los_Angeles)          |
| Westchester, Los Angeles (<http://dbpedia.org/resource/Westchester,_Los_Angeles>) | pushpin map (dbp:pushpinMap)                                        | United States Los Angeles Western (en)                                   |
| Westchester, Los Angeles (<http://dbpedia.org/resource/Westchester,_Los_Angeles>) | settlement type (dbp:settlementType)                                | Neighborhoods of Los Angeles (dbr:Neighborhoods_of_Los_Angeles)          |
| Westchester, Los Angeles (<http://dbpedia.org/resource/Westchester,_Los_Angeles>) | image caption (dbp:imageCaption)                                    | "Westchester, Home of LAX" sign at Westchester Rec Center (en)           |
| ...                                                                               | ...                                                                 | ...                                                                      |

[Tool] Got no rows and 3 columns

[Tool]
Got 102 rows and 3 columns, showing the first 10 rows below:
| subject                                                                           | property                                                            | object                                                                   |
| --------------------------------------------------------------------------------- | ------------------------------------------------------------------- | ------------------------------------------------------------------------ |
| Westchester, Los Angeles (<http://dbpedia.org/resource/Westchester,_Los_Angeles>) | has abstract (dbo:abstract)                                         | Westchester – dzielnica w zachod... Otis College of Art and Design. (pl) |
| Westchester, Los Angeles (<http://dbpedia.org/resource/Westchester,_Los_Angeles>) | Wikipage page ID (dbo:wikiPageID)                                   | 481156 (xsd:int)                                                         |
| Westchester, Los Angeles (<http://dbpedia.org/resource/Westchester,_Los_Angeles>) | Wikipage revision ID (dbo:wikiPageRevisionID)                       | 1112956221 (xsd:int)                                                     |
| Westchester, Los Angeles (<http://dbpedia.org/resource/Westchester,_Los_Angeles>) | page length (characters) of wiki page (dbo:wikiPageLength)          | 30587 (xsd:int)                                                          |
| Westchester, Los Angeles (<http://dbpedia.org/resource/Westchester,_Los_Angeles>) | Link from a Wikipage to an external page (dbo:wikiPageExternalLink) | <http://www.ncwpdr.org/>                                                 |
| Westchester, Los Angeles (<http://dbpedia.org/resource/Westchester,_Los_Angeles>) | name (dbp:name)                                                     | Westchester (en)                                                         |
| Westchester, Los Angeles (<http://dbpedia.org/resource/Westchester,_Los_Angeles>) | type (dbo:type)                                                     | Neighborhoods of Los Angeles (dbr:Neighborhoods_of_Los_Angeles)          |
| Westchester, Los Angeles (<http://dbpedia.org/resource/Westchester,_Los_Angeles>) | pushpin map (dbp:pushpinMap)                                        | United States Los Angeles Western (en)                                   |
| Westchester, Los Angeles (<http://dbpedia.org/resource/Westchester,_Los_Angeles>) | settlement type (dbp:settlementType)                                | Neighborhoods of Los Angeles (dbr:Neighborhoods_of_Los_Angeles)          |
| Westchester, Los Angeles (<http://dbpedia.org/resource/Westchester,_Los_Angeles>) | image caption (dbp:imageCaption)                                    | "Westchester, Home of LAX" sign at Westchester Rec Center (en)           |
| ...                                                                               | ...                                                                 | ...                                                                      |

[Tool] Got no rows and 3 columns

[Tool] Got no rows and 3 columns

[Tool] Got no rows and 3 columns

[Assistant]
It appears that the location entities (such as neighborhoods or cities) are not directly linked to dbr:California via a "state" or "isPartOf" property. However, many airports in California will have their dbp:location or dbo:location property containing the string "California".

Therefore, a practical approach is to select all airports whose dbp:location or dbo:location contains "California". I will construct a SPARQL query that finds all airports (rdf:type dbo:Airport) where either dbp:location or dbo:location contains "California" in its label.

I will also include optional labels for human readability.

[Tool]
Got 218 rows and 1 column, showing the first 5 and last 5 rows below:
| airport                                                                   |
| ------------------------------------------------------------------------- |
| Agua Dulce Airpark (dbr:Agua_Dulce_Airpark)                               |
| Alfonsina's Airstrip (<http://dbpedia.org/resource/Alfonsina's_Airstrip>) |
| Alum Rock Airport (dbr:Alum_Rock_Airport)                                 |
| Amboy Airfield (dbr:Amboy_Airfield)                                       |
| Amedee Army Airfield (dbr:Amedee_Army_Airfield)                           |
| ...                                                                       |
| Weaverville Airport (dbr:Weaverville_Airport)                             |
| Weed Airport (dbr:Weed_Airport)                                           |
| Willits Municipal Airport (dbr:Willits_Municipal_Airport)                 |
| Woodlake Airport (dbr:Woodlake_Airport)                                   |
| Zamperini Field (dbr:Zamperini_Field)                                     |

[Tool]
Got 218 rows and 2 columns, showing the first 5 and last 5 rows below:
| airport                                                                                | label                          |
| ---------------------------------------------------------------------------------------------------------- | ------------------------------ |
| dbr:NASA_Crows_Landing_Airport__Naval_Auxiliary_Air_Station_Crows_Landing__1                               |                                |
| dbr:Oakland_International_Airport__Oakland_International_Airport__1                                        |                                |
| dbr:Rogers_Field__Rogers_Field__1                                                                          |                                |
| dbr:University_Airport__University_Airport__1                                                              |                                |
| <http://dbpedia.org/resource/Arcata–Eureka_Airport__California_Redwood_Coast_–_Humboldt_County_Airport__1> |                                |
| ...                                                                                | ...                            |
| Weaverville Airport (dbr:Weaverville_Airport)                                                              | Weaverville Airport (en)       |
| Weed Airport (dbr:Weed_Airport)                                                                            | Weed Airport (en)              |
| Willits Municipal Airport (dbr:Willits_Municipal_Airport)                                                  | Willits Municipal Airport (en) |
| Woodlake Airport (dbr:Woodlake_Airport)                                                                    | Woodlake Airport (en)          |
| Zamperini Field (dbr:Zamperini_Field)                                                                      | Zamperini Field (en)           |

[Tool] Stopped generation process

[User]
Feedback (status=refine):
The query is a good attempt and retrieves airports whose location property contains 'California', but it relies on string matching, which can be imprecise and may miss airports whose location is linked via a resource (e.g., dbr:California) rather than a string literal. To improve precision and completeness, the query should also check for airports where the location property (dbo:location or dbp:location) is directly linked to the DBpedia resource for California (dbr:California). Consider adding a triple pattern like '?airport dbo:location dbr:California' or '?airport dbp:location dbr:California' in addition to the current string matching. This will ensure that all relevant airports are included, regardless of how the location is represented.

[Assistant]
Thank you for the feedback. You are correct: to improve both precision and completeness, the query should also include airports whose dbo:location or dbp:location is directly linked to the resource dbr:California, not just those with a string literal containing "California".

Here's my plan:
- Keep the current string matching for "California" in location literals.
- Add triple patterns for airports where dbo:location or dbp:location is dbr:California.
- Return the airport IRIs and optional English labels.

I will now construct and execute this improved query.

[Tool]
Got 218 rows and 2 columns, showing the first 5 and last 5 rows below:
| airport                                                                                | label                          |
| ---------------------------------------------------------------------------------------------------------- | ------------------------------ |
| dbr:NASA_Crows_Landing_Airport__Naval_Auxiliary_Air_Station_Crows_Landing__1                               |                                |
| dbr:Oakland_International_Airport__Oakland_International_Airport__1                                        |                                |
| dbr:Rogers_Field__Rogers_Field__1                                                                          |                                |
| dbr:University_Airport__University_Airport__1                                                              |                                |
| <http://dbpedia.org/resource/Arcata–Eureka_Airport__California_Redwood_Coast_–_Humboldt_County_Airport__1> |                                |
| ...                                                                                | ...                            |
| Weaverville Airport (dbr:Weaverville_Airport)                                                              | Weaverville Airport (en)       |
| Weed Airport (dbr:Weed_Airport)                                                                            | Weed Airport (en)              |
| Willits Municipal Airport (dbr:Willits_Municipal_Airport)                                                  | Willits Municipal Airport (en) |
| Woodlake Airport (dbr:Woodlake_Airport)                                                                    | Woodlake Airport (en)          |
| Zamperini Field (dbr:Zamperini_Field)                                                                      | Zamperini Field (en)           |

[Tool] Stopped generation process

[User]
Feedback (status=refine):
The query is generally well-constructed and retrieves airports in California by considering both string matches and direct links to the California resource. However, there are a few areas for refinement:

1. The query currently retrieves some IRIs that appear to be concatenations or non-standard (e.g., IRIs ending with '__1'), which may not correspond to actual DBpedia resources. Consider filtering out such IRIs if possible, or ensure only standard airport IRIs are returned.
2. The query could be further improved by also considering airports whose 'dbo:state' or similar properties point to California, as some airports might use this property instead of 'location'.
3. The use of both 'dbp:location' and 'dbo:location' is good, but you might also want to check for 'dbp:state' and 'dbo:state' properties.

Overall, the query is close to complete, but a bit more refinement could improve the precision and completeness of the results.

[Assistant]
Thank you for the detailed feedback. Here’s how I’ll address each point:

1. **Non-standard IRIs:** I will filter out IRIs that contain double underscores '__', as these are likely artifacts or non-standard resources in DBpedia.
2. **State properties:** I will include dbo:state and dbp:state properties, checking both for direct links to dbr:California and for string matches containing "California".
3. **Comprehensive coverage:** I will keep the existing checks for dbp:location and dbo:location, both as direct links and string matches.

Here’s my plan for the refined query:
- Retrieve airports (rdf:type dbo:Airport).
- Include airports where any of dbo:location, dbp:location, dbo:state, or dbp:state is dbr:California.
- Include airports where any of those properties is a string literal containing "California".
- Filter out IRIs with '__' to avoid non-standard resources.
- Return airport IRIs and optional English labels.

Now, I will construct and execute this refined query.

[Tool]
Got 131 rows and 2 columns, showing the first 5 and last 5 rows below:
| airport                                                                                | label                                  |
| --------------------------------------------------------------------------------------------------- | -------------------------------------- |
| Alfonsina's Airstrip (<http://dbpedia.org/resource/Alfonsina's_Airstrip>)                           | Alfonsina's Airstrip (en)              |
| Alum Rock Airport (dbr:Alum_Rock_Airport)                                                           | Alum Rock Airport (en)                 |
| Amboy Airfield (dbr:Amboy_Airfield)                                                                 | Amboy Airfield (en)                    |
| Amedee Army Airfield (dbr:Amedee_Army_Airfield)                                                     | Amedee Army Airfield (en)              |
| Apple Valley Airport (California) (<http://dbpedia.org/resource/Apple_Valley_Airport_(California)>) | Apple Valley Airport (California) (en) |
| ...                                                                                | ...                                    |
| Watsonville Municipal Airport (dbr:Watsonville_Municipal_Airport)                                   | Watsonville Municipal Airport (en)     |
| Weaverville Airport (dbr:Weaverville_Airport)                                                       | Weaverville Airport (en)               |
| Weed Airport (dbr:Weed_Airport)                                                                     | Weed Airport (en)                      |
| Willits Municipal Airport (dbr:Willits_Municipal_Airport)                                           | Willits Municipal Airport (en)         |
| Woodlake Airport (dbr:Woodlake_Airport)                                                             | Woodlake Airport (en)                  |

[Tool] Stopped generation process


PREFIX dbp: <http://dbpedia.org/property/>
SELECT ?person ?property ?nickname WHERE {
  VALUES ?property {
    dbp:nickname dbp:nicknames
  }
  ?person ?property ?nickname .
  FILTER ( lcase( str( ?nickname ) ) = "rodzilla" )
}

After running a query that explicitly checks both dbp:nickname and dbp:nicknames for the value "Rodzilla", there are no results in DBpedia directly connecting Dennis Rodman (or any entity) to the nickname "Rodzilla" via these properties.

Therefore, while Dennis Rodman is widely known as "Rodzilla" in popular culture, DBpedia does not currently contain a triple that explicitly links him to this nickname using the standard nickname properties.

Here is the refined SPARQL query that demonstrates this search:

```sparql
SELECT ?person ?property ?nickname WHERE {
  VALUES ?property { dbp:nickname dbp:nicknames }
  ?person ?property ?nickname .
  FILTER (lcase(str(?nickname)) = "rodzilla")
}
```

No results are returned, so DBpedia does not explicitly encode this nickname connection. If you need explicit evidence from DBpedia, it is not available at this time.

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

You have access to the following knowledge graphs:
dbpedia at https://qlever.cs.uni-freiburg.de/api/dbpedia

You can use the following SPARQL prefixes implicitly in all functions:
dbo: <http://dbpedia.org/ontology/
dbp: <http://dbpedia.org/property/
dbr: <http://dbpedia.org/resource/
dc: <http://purl.org/dc/terms/
foaf: <http://xmlns.com/foaf/0.1/
owl: <http://www.w3.org/2002/07/owl#
prov: <http://www.w3.org/ns/prov#
purl: <http://purl.org/linguistics/gold/
rdf: <http://www.w3.org/1999/02/22-rdf-syntax-ns#
rdfs: <http://www.w3.org/2000/01/rdf-schema#
schema: <http://schema.org/
skos: <http://www.w3.org/2004/02/skos/core#
xsd: <http://www.w3.org/2001/XMLSchema#
geo: <http://www.opengis.net/ont/geosparql#
geosparql: <http://www.opengis.net/ont/geosparql#
gn: <http://www.geonames.org/ontology#
bd: <http://www.bigdata.com/rdf#
hint: <http://www.bigdata.com/queryHints#
wikibase: <http://wikiba.se/ontology#
qb: <http://purl.org/linked-data/cube#
void: <http://rdfs.org/ns/void#

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. Use the functions to search for 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. Use the execute function to get feedback on intermediate queries. You can go back and forth between knowledge graph searches and SPARQL query executions to refine the query.
4. Use the answer or cancel function to finalize your answer and stop the generation process.

Additional rules:
1. Explain your thought process before and after each step and function call.
2. Do not assume or make up any entities or properties without verifying them with the knowledge graphs and functions.
3. 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.
4. 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.
5. 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.
6. For questions with a "True" or "False" answer the SPARQL query should be an ASK query.
7. 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.

[User] Who was called Rodzilla?

[Assistant]
Let's break down the question:

1. The user is asking for the entity (person) who was called "Rodzilla".
2. "Rodzilla" is likely a nickname.
3. I need to find which property in DBpedia is used for nicknames, and then search for the value "Rodzilla".

Step 1: Search for the property related to "nickname" in DBpedia.

[Tool]
Top 10 property alternatives:
1. nickname (dbp:nickname)
2. nicknames (dbp:nicknames)
3. Nickname/s (<http://dbpedia.org/property/nickname/s>)
4. nickname type (dbp:nicknameType)
5. Nickname   founded (dbp:nicknameFounded)
6. 7 nickname (dbp:7Nickname)
7. nickname subunit  (dbp:nicknameSubunit)
8. nickname link (dbp:nicknameLink)
9. sports nickname (dbp:sportsNickname)
10. sports nicknames (dbp:sportsNicknames)

[Assistant]
The most relevant properties for "nickname" are dbp:nickname and dbp:nicknames.

Step 2: Search for entities that have the nickname "Rodzilla" using these properties. I'll start by searching for subjects with dbp:nickname "Rodzilla".

[Tool]
Failed to call function search_object_of_property:
synonyms not found in row 161: '''

[Tool] Got no rows and 1 columns

[Tool] Got no rows and 1 columns

[Tool]
Top 10 entity alternatives:
1. Rodzilla (dbr:Rodzilla)

[Tool]
Got 9 rows and 3 columns:
| subject                 | property                                                   | object                                                       |
| ----------------------- | ---------------------------------------------------------- | ------------------------------------------------------------ |
| Rodzilla (dbr:Rodzilla) | Wikipage page ID (dbo:wikiPageID)                          | 5539183 (xsd:int)                                            |
| Rodzilla (dbr:Rodzilla) | Wikipage revision ID (dbo:wikiPageRevisionID)              | 879079551 (xsd:int)                                          |
| Rodzilla (dbr:Rodzilla) | page length (characters) of wiki page (dbo:wikiPageLength) | 202 (xsd:int)                                                |
| Rodzilla (dbr:Rodzilla) | dbp:wikiPageUsesTemplate                                   | <http://dbpedia.org/resource/Template:Hndis>                 |
| Rodzilla (dbr:Rodzilla) | rdfs:label                                                 | Rodzilla (en)                                                |
| Rodzilla (dbr:Rodzilla) | owl:sameAs                                                 | <http://www.wikidata.org/entity/Q7357506>                    |
| Rodzilla (dbr:Rodzilla) | prov:wasDerivedFrom                                        | <http://en.wikipedia.org/wiki/Rodzilla?oldid=879079551&ns=0> |
| Rodzilla (dbr:Rodzilla) | foaf:isPrimaryTopicOf                                      | <http://en.wikipedia.org/wiki/Rodzilla>                      |
| Rodzilla (dbr:Rodzilla) | owl:sameAs                                                 | <https://global.dbpedia.org/id/4ujdX>                        |

[Tool] Got no rows and 1 columns

[Tool] Got no rows and 1 columns

[Tool]
SPARQL execution failed:
Operation timed out.

[Tool]
Got 9 rows and 3 columns:
| subject                 | property                                                   | object                                                       |
| ----------------------- | ---------------------------------------------------------- | ------------------------------------------------------------ |
| Rodzilla (dbr:Rodzilla) | Wikipage page ID (dbo:wikiPageID)                          | 5539183 (xsd:int)                                            |
| Rodzilla (dbr:Rodzilla) | Wikipage revision ID (dbo:wikiPageRevisionID)              | 879079551 (xsd:int)                                          |
| Rodzilla (dbr:Rodzilla) | page length (characters) of wiki page (dbo:wikiPageLength) | 202 (xsd:int)                                                |
| Rodzilla (dbr:Rodzilla) | dbp:wikiPageUsesTemplate                                   | <http://dbpedia.org/resource/Template:Hndis>                 |
| Rodzilla (dbr:Rodzilla) | rdfs:label                                                 | Rodzilla (en)                                                |
| Rodzilla (dbr:Rodzilla) | owl:sameAs                                                 | <http://www.wikidata.org/entity/Q7357506>                    |
| Rodzilla (dbr:Rodzilla) | prov:wasDerivedFrom                                        | <http://en.wikipedia.org/wiki/Rodzilla?oldid=879079551&ns=0> |
| Rodzilla (dbr:Rodzilla) | foaf:isPrimaryTopicOf                                      | <http://en.wikipedia.org/wiki/Rodzilla>                      |
| Rodzilla (dbr:Rodzilla) | owl:sameAs                                                 | <https://global.dbpedia.org/id/4ujdX>                        |

[Tool] Got no rows and 1 columns

[Tool] Got no rows and 1 columns

[Tool]
Got 65,536 rows and 3 columns, showing the first 10 rows below:
| subject                                                                 | property                | object                                        |
| ----------------------------------------------------------------------- | ----------------------- | --------------------------------------------- |
| André Masséna (<http://dbpedia.org/resource/André_Masséna>)             | nickname (dbp:nickname) | l'Enfant chéri de la Victoire (en)            |
| Hoboken, New Jersey (<http://dbpedia.org/resource/Hoboken,_New_Jersey>) | nickname (dbp:nickname) | The Mile Square City (en)                     |
| Rennes 2 University (dbr:Rennes_2_University)                           | nickname (dbp:nickname) | "Rennes 2 la Rouge" (en)                      |
| Joseph Stalin (dbr:Joseph_Stalin)                                       | nickname (dbp:nickname) | Koba (en)                                     |
| Central Hardin High School (dbr:Central_Hardin_High_School)             | nickname (dbp:nickname) | American black bear (dbr:American_black_bear) |
| Adams State Grizzlies (dbr:Adams_State_Grizzlies)                       | nickname (dbp:nickname) | Grizzly bear (dbr:Grizzly_bear)               |
| Nelson Mandela (dbr:Nelson_Mandela)                                     | nickname (dbp:nickname) |  (en)                                         |
| List of Russian monarchs (dbr:List_of_Russian_monarchs)                 | nickname (dbp:nickname) | Kalita (en)                                   |
| América de Cali (<http://dbpedia.org/resource/América_de_Cali>)         | nickname (dbp:nickname) | La Mechita (en)                               |
| Rome (dbr:Rome)                                                         | nickname (dbp:nickname) | Throne of St. Peter (en)                      |
| ...                                                                     | ...                     | ...                                           |

[Tool]
Got 3,838 rows and 3 columns, showing the first 10 rows below:
| subject                                                                         | property                  | object                                                         |
| ------------------------------------------------------------------------------- | ------------------------- | -------------------------------------------------------------- |
| Brussels (dbr:Brussels)                                                         | nicknames (dbp:nicknames) | Capital of Europe, Comic City (en)                             |
| Albuquerque, New Mexico (<http://dbpedia.org/resource/Albuquerque,_New_Mexico>) | nicknames (dbp:nicknames) | ABQ, Burque, The 505, The Duke City, The Q (en)                |
| Jakarta (dbr:Jakarta)                                                           | nicknames (dbp:nicknames) |  (en)                                                          |
| List of Regular Show characters (dbr:List_of_Regular_Show_characters)           | nicknames (dbp:nicknames) | Fives (en)                                                     |
| Guangzhou (dbr:Guangzhou)                                                       | nicknames (dbp:nicknames) | City of Rams, City of Flowers, City of Rice Spike (en)         |
| Baltimore (dbr:Baltimore)                                                       | nicknames (dbp:nicknames) | Charm City; B'more; Mobtown (en)                               |
| Birmingham (dbr:Birmingham)                                                     | nicknames (dbp:nicknames) | 121 (xsd:int)                                                  |
| Edinburgh (dbr:Edinburgh)                                                       | nicknames (dbp:nicknames) | "Auld Reekie", "Edina", "Athens of the North" (en)             |
| Bangalore (dbr:Bangalore)                                                       | nicknames (dbp:nicknames) | Silicon Valley of India, Garden City, IT Capital of India (en) |
| Athens (dbr:Athens)                                                             | nicknames (dbp:nicknames) | , tò iostephès ásty (en)                                       |
| ...                                                                             | ...                       | ...                                                            |

[Tool]
Top 10 entity alternatives:
1. Dennis Rodman (dbr:Dennis_Rodman): Dennis Keith Rodman (born May 13, 1961) is an American former pr...ard position in his early years before becoming a power forward.
2. Rodman, Dennis (<http://dbpedia.org/resource/Rodman,_Dennis>)
3. Dennis Rodman Jr. (dbr:Dennis_Rodman_Jr.)
4. Dennis Rodman (song) (<http://dbpedia.org/resource/Dennis_Rodman_(song)>)
5. Dennis Rodman's Big Bang in Pyongyang (<http://dbpedia.org/resource/Dennis_Rodman's_Big_Bang_in_Pyongyang>): Dennis Rodman's Big Bang in Pyongyang is a 2015 documentary film...between former NBA stars and the North Korean team in Pyongyang.
6. List of career achievements by Dennis Rodman (dbr:List_of_career_achievements_by_Dennis_Rodman): This page details the career achievements of American basketball player Dennis Rodman.
7. Dennis, also known as Denny (dbr:Dennis)
8. Eugene Parks Wilkinson, also known as Dennis (dbr:Eugene_Parks_Wilkinson): Eugene Parks "Dennis" Wilkinson (August 10, 1918 – July 11, 2013...officer of USS Long Beach, America's first nuclear surface ship.
9. Tse Chi Lop, also known as T1, Sam Gor, Dennis, Brother No. 3, Ah Lap (dbr:Tse_Chi_Lop): Tse Chi Lop (謝志樂, born 1963) is the alleged kingpin behind Asia-...d Xie Zii. Some police forces refer to Tse as "T1" (top target).
10. Dennis Reksten, also known as Dennis (dbr:Dennis_Reksten): Sven Johan Reksten (born 12 September 1949 in Bergen, Norway), a...mposer and music producer, known from bands like Elektrisk Regn.

[Tool]
Top 10 property alternatives:
1. names (dbp:names)
2. name (dbp:name)
3. birth name (dbp:birthName)
4. champion (dbp:champion)
5. leader (dbp:leader)
6. debut (dbp:debut)
7. birth place (dbo:birthPlace): where the person was born, animal, place
8. birth place (dbp:birthPlace)
9. award (dbo:award): Award won by a Person, Musical or other Work, RaceHorse, Building, etc, award
10. birth date (dbo:birthDate): xsd:date, animal

No other items found

[Tool]
Got 433 rows and 3 columns, showing the first 10 rows below:
| subject                           | property                                                            | object                                                                   |
| --------------------------------- | ------------------------------------------------------------------- | ------------------------------------------------------------------------ |
| Dennis Rodman (dbr:Dennis_Rodman) | has abstract (dbo:abstract)                                         | Dennis Keith Rodman (* 13. Mai 1...nd Rebounder der NBA-Geschichte. (de) |
| Dennis Rodman (dbr:Dennis_Rodman) | Wikipage page ID (dbo:wikiPageID)                                   | 355502 (xsd:int)                                                         |
| Dennis Rodman (dbr:Dennis_Rodman) | Wikipage revision ID (dbo:wikiPageRevisionID)                       | 1124595918 (xsd:int)                                                     |
| Dennis Rodman (dbr:Dennis_Rodman) | page length (characters) of wiki page (dbo:wikiPageLength)          | 144265 (xsd:int)                                                         |
| Dennis Rodman (dbr:Dennis_Rodman) | Link from a Wikipage to an external page (dbo:wikiPageExternalLink) | <http://www.cagematch.net/%3Fid=2&nr=6407&gimmick=Dennis+Rodman>         |
| Dennis Rodman (dbr:Dennis_Rodman) | name (dbp:name)                                                     | Dennis Rodman (en)                                                       |
| Dennis Rodman (dbr:Dennis_Rodman) | title (dbp:title)                                                   | Dennis Rodman – Basketball career (en)                                   |
| Dennis Rodman (dbr:Dennis_Rodman) | date (dbp:date)                                                     | 2012-04-14 (xsd:date)                                                    |
| Dennis Rodman (dbr:Dennis_Rodman) | career station (dbo:careerStation)                                  | dbr:Dennis_Rodman__CareerStation__1                                      |
| Dennis Rodman (dbr:Dennis_Rodman) | birth place (dbp:birthPlace)                                        | Trenton, New Jersey (<http://dbpedia.org/resource/Trenton,_New_Jersey>)  |
| ...                               | ...                                                                 | ...                                                                      |

[Assistant]
After searching for the nickname "Rodzilla" in the relevant nickname properties and not finding a direct match, I searched for the entity "Rodzilla" and found that it exists as a disambiguation page. I then checked Dennis Rodman's properties, but there is no explicit "nickname" property for him in DBpedia.

However, based on external knowledge and the context, Dennis Rodman is widely known as "Rodzilla." The DBpedia entity for Dennis Rodman is dbr:Dennis_Rodman.

Here is a SPARQL query that returns the IRI for Dennis Rodman, who is known as "Rodzilla."

[Tool] Stopped generation process

[User]
Feedback (status=refine):
The answer is correct: Dennis Rodman is indeed known as 'Rodzilla.' However, the SPARQL query does not demonstrate why or how Dennis Rodman is associated with the nickname 'Rodzilla.' It simply returns the IRI for Dennis Rodman without showing any connection to the nickname. Ideally, the query should look for a property such as 'nickname' or 'alias' and filter for 'Rodzilla' to provide evidence for the answer. Please refine the query to explicitly show the connection between Dennis Rodman and the nickname 'Rodzilla.'

[Assistant]
Thank you for the feedback. You are correct: the ideal SPARQL query should explicitly demonstrate the connection between Dennis Rodman and the nickname "Rodzilla" using properties such as dbp:nickname or dbp:nicknames.

From my previous exploration, I did not find a direct triple in DBpedia connecting Dennis Rodman to "Rodzilla" via dbp:nickname or dbp:nicknames. However, to be thorough, I will construct a query that searches for any entity with a nickname or nicknames property containing "Rodzilla" and returns both the entity and the property used, as well as the value. This will provide explicit evidence if such a connection exists.

Let me write a query that checks both dbp:nickname and dbp:nicknames for the value "Rodzilla" (case-insensitive), and returns the entity, the property, and the value.

[Tool] Got no rows and 3 columns

[Assistant]
After running a query that explicitly checks both dbp:nickname and dbp:nicknames for the value "Rodzilla", there are no results in DBpedia directly connecting Dennis Rodman (or any entity) to the nickname "Rodzilla" via these properties.

Therefore, while Dennis Rodman is widely known as "Rodzilla" in popular culture, DBpedia does not currently contain a triple that explicitly links him to this nickname using the standard nickname properties.

Here is the refined SPARQL query that demonstrates this search:

```sparql
SELECT ?person ?property ?nickname WHERE {
  VALUES ?property { dbp:nickname dbp:nicknames }
  ?person ?property ?nickname .
  FILTER (lcase(str(?nickname)) = "rodzilla")
}
```

No results are returned, so DBpedia does not explicitly encode this nickname connection. If you need explicit evidence from DBpedia, it is not available at this time.

[User]
Feedback (status=done):
The answer is correct and complete in its current form. The SPARQL query is well-constructed, directly searching for entities with the nickname 'Rodzilla' using both dbp:nickname and dbp:nicknames properties. The explanation accurately reflects the query's result and clarifies that, although Dennis Rodman is known as 'Rodzilla' in popular culture, DBpedia does not currently encode this information explicitly. No further refinement is needed.


PREFIX dbp: <http://dbpedia.org/property/>
PREFIX xsd: <http://www.w3.org/2001/XMLSchema#>
PREFIX dbr: <http://dbpedia.org/resource/>
SELECT ?ibm ?amount ?currency WHERE {
  VALUES ?ibm {
    dbr:IBM
  }
  OPTIONAL {
    ?ibm dbp:revenue ?amount .
    FILTER ( datatype( ?amount ) = xsd:int )
  }
  OPTIONAL {
    ?ibm dbp:revenue ?currency .
    FILTER ( datatype( ?currency ) != xsd:int )
  }
}

IBM's revenue is 57,350,000,000 USD. (IRI: dbr:IBM, amount: 57350000000, currency: USD)

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

You have access to the following knowledge graphs:
dbpedia at https://qlever.cs.uni-freiburg.de/api/dbpedia

You can use the following SPARQL prefixes implicitly in all functions:
dbo: <http://dbpedia.org/ontology/
dbp: <http://dbpedia.org/property/
dbr: <http://dbpedia.org/resource/
dc: <http://purl.org/dc/terms/
foaf: <http://xmlns.com/foaf/0.1/
owl: <http://www.w3.org/2002/07/owl#
prov: <http://www.w3.org/ns/prov#
purl: <http://purl.org/linguistics/gold/
rdf: <http://www.w3.org/1999/02/22-rdf-syntax-ns#
rdfs: <http://www.w3.org/2000/01/rdf-schema#
schema: <http://schema.org/
skos: <http://www.w3.org/2004/02/skos/core#
xsd: <http://www.w3.org/2001/XMLSchema#
geo: <http://www.opengis.net/ont/geosparql#
geosparql: <http://www.opengis.net/ont/geosparql#
gn: <http://www.geonames.org/ontology#
bd: <http://www.bigdata.com/rdf#
hint: <http://www.bigdata.com/queryHints#
wikibase: <http://wikiba.se/ontology#
qb: <http://purl.org/linked-data/cube#
void: <http://rdfs.org/ns/void#

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. Use the functions to search for 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. Use the execute function to get feedback on intermediate queries. You can go back and forth between knowledge graph searches and SPARQL query executions to refine the query.
4. Use the answer or cancel function to finalize your answer and stop the generation process.

Additional rules:
1. Explain your thought process before and after each step and function call.
2. Do not assume or make up any entities or properties without verifying them with the knowledge graphs and functions.
3. 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.
4. 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.
5. 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.
6. For questions with a "True" or "False" answer the SPARQL query should be an ASK query.
7. 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.

[User] What is the revenue of IBM?

[Assistant]
Let's break down the question:

1. The entity is "IBM", which stands for International Business Machines Corporation.
2. The property of interest is "revenue".

First, I will search for the entity "IBM" in DBpedia to confirm its IRI.

[Tool]
Top 10 entity alternatives:
1. IBM (dbr:IBM): International Business Machines Corporation (IBM) is an American...(CTR) and was renamed "International Business Machines" in 1924.
2. IBM (<http://dbpedia.org/resource/Category:IBM>)
3. @IBM (<http://dbpedia.org/resource/@IBM>)
4. Ibm (dbr:Ibm)
5. .ibm (dbr:.ibm)
6. IBMX, also known as 3-Isobutyl-1-methylxanthine (dbr:IBMX): IBMX (3-isobutyl-1-methylxanthine), like other methylated xanthi...itor, IBMX has IC50 = 2–50 μM and does not inhibit PDE8 or PDE9.
7. IBM System/360 (<http://dbpedia.org/resource/IBM_System/360>): The IBM System/360 (S/360) is a family of mainframe computer sys...BM to release a suite of compatible designs at different prices.
8. IBM AIX (dbr:IBM_AIX): AIX (Advanced Interactive eXecutive, pronounced , “ay-eye-ex”), ...developed and sold by IBM for several of its computer platforms.
9. IBM Db2 (dbr:IBM_Db2)
10. IBM PS/2 (<http://dbpedia.org/resource/IBM_PS/2>)

[Assistant]
The correct entity for IBM is dbr:IBM.

Next, I need to find the property related to "revenue" for this entity. I'll search for properties of dbr:IBM related to "revenue".

[Tool]
Top 10 property alternatives:
1. revenue (dbp:revenue)
2. net income (dbp:netIncome)
3. operating income ($) (dbo:operatingIncome): xsd:double, company
4. operating income (dbp:operatingIncome)
5. net income ($) (dbo:netIncome): xsd:double, company
6. assets (dbp:assets)
7. equity ($) (dbo:equity): xsd:double, company
8. assets ($) (dbo:assets): Assets and liabilities are part of a companis balance sheet. In ... is held to have positive economic value is considered an asset., xsd:double, company
9. industry (dbo:industry): company
10. industry (dbp:industry)

No other items found

[Assistant]
The most relevant property for IBM's revenue is dbp:revenue.

Now, I will construct a SPARQL query to retrieve the revenue of dbr:IBM using the dbp:revenue property. I will also try to include an optional label for clarity.

[Tool]
Got 2 rows and 1 column:
| revenue               |
| --------------------- |
| 57350000000 (xsd:int) |
| USD (en)              |

[Tool] Stopped generation process

[User]
Feedback (status=refine):
The SPARQL query is mostly correct and retrieves the revenue information for IBM. However, the result contains two rows: one with the numeric value (57350000000) and one with the currency (USD). This suggests that the revenue property is stored as a list or as multiple values (amount and currency) in DBpedia. The answer should clarify this and ideally combine both values into a single, human-readable string (e.g., '57350000000 USD') within the SPARQL query itself, or at least return both values in separate variables for clarity. Consider refining the query to retrieve both the amount and the currency in separate variables, if possible, to avoid ambiguity.

[Assistant]
Thank you for the feedback. The previous query returned two separate rows for the revenue property: one with the numeric value and one with the currency ("USD"). This suggests that the revenue information is stored as multiple values under the same property, rather than as a structured object.

To improve clarity, I will refine the query to retrieve both the numeric value and the currency as separate variables. I will do this by filtering the results: one for the numeric value (using a FILTER for numeric datatype), and one for the currency (using a FILTER for string "USD"). Then, I will combine them in the SELECT clause.

Let's proceed step by step:

1. Retrieve all values for dbp:revenue for dbr:IBM and inspect their types.
2. Use FILTERs to separate the numeric value and the currency.
3. Return both in a single result.

First, let's check the datatypes of the values returned for dbp:revenue.

[Tool]
Got 2 rows and 2 columns:
| revenue               | type                            |
| --------------------- | ------------------------------- |
| 57350000000 (xsd:int) | xsd:int                         |
| USD (en)              | rdf:langString (rdf:langString) |

[Assistant]
The results confirm that the numeric value has the datatype xsd:int, and the currency ("USD") is a language-tagged string.

Now, I will write a SPARQL query that:
- Retrieves the numeric value as ?amount (FILTER for xsd:int)
- Retrieves the currency as ?currency (FILTER for "USD")
- Returns both in a single result

I'll use subqueries or OPTIONAL patterns to achieve this.

[Tool]
Got 1 row and 2 columns:
| amount                | currency |
| --------------------- | -------- |
| 57350000000 (xsd:int) | USD (en) |

[Tool] Stopped generation process

[User]
Feedback (status=refine):
The query retrieves the revenue amount and attempts to get the currency as a separate value, but the way it tries to extract the currency is not robust. The 'dbp:revenue' property on DBpedia often stores the revenue as a literal string (e.g., 'US$57.35 billion (2020)'), not as a structured integer and currency. The current query only works if the revenue is stored as an xsd:int and separately as a currency string, which is rarely the case. To improve, the query should retrieve the revenue as a string literal and, if possible, extract the numeric value and currency using SPARQL string functions. Also, the query should always return the IRI (dbr:IBM) as part of the result, as per the guidelines. Please refine the query to robustly extract the revenue information from DBpedia.

[Assistant]
Thank you for the detailed feedback. You are correct: in DBpedia, the dbp:revenue property is often a single string literal (e.g., "US$57.35 billion (2020)") rather than structured data. Therefore, the best approach is to retrieve the revenue as a string literal and, if possible, use SPARQL string functions to extract the numeric value and currency.

Additionally, I will ensure the result includes the IRI for IBM (dbr:IBM) as required.

Here’s my plan:
1. Retrieve the dbp:revenue property as a string for dbr:IBM.
2. Optionally, use SPARQL string functions to extract the currency and numeric value if the format allows.
3. Always include dbr:IBM in the result.

Let’s first check the actual value of dbp:revenue for dbr:IBM as a string.

[Tool]
Got 2 rows and 2 columns:
| ibm           | revenue               |
| ------------- | --------------------- |
| IBM (dbr:IBM) | 57350000000 (xsd:int) |
| IBM (dbr:IBM) | USD (en)              |

[Assistant]
The dbp:revenue property for dbr:IBM is stored as two separate values: one as an integer (57350000000) and one as a string ("USD"). This is not the typical string-literal format (like "US$57.35 billion (2020)") found for some other companies, but rather as separate values for amount and currency.

To robustly handle this, I will:
- Return both the integer value and the currency string as separate variables.
- Always include the IRI (dbr:IBM) in the result.
- Use GROUP BY or aggregation to ensure a single row per company, if possible.

Here is a refined query that returns the IRI, the numeric revenue, and the currency as separate variables, using GROUP_CONCAT to combine multiple values if needed.

[Tool]
Failed to call function execute:
failed to parse input: parse error at position 276 for token UNDEF with content 'UNDEF' (the input most likely does not follow the grammar)

[Assistant]
The error occurred because the UNDEF keyword is not supported in SPARQL for conditional BINDs. Instead, I will use OPTIONAL patterns to separately retrieve the integer and string values for revenue, and then return them in the same row for dbr:IBM.

Here’s how I’ll proceed:
- Use two OPTIONAL clauses: one for the integer value, one for the string value.
- Return all three: the IRI, the amount, and the currency.

Let’s try this approach.

[Tool]
Got 1 row and 3 columns:
| ibm           | amount                | currency |
| ------------- | --------------------- | -------- |
| IBM (dbr:IBM) | 57350000000 (xsd:int) | USD (en) |

[Tool] Stopped generation process


PREFIX dbo: <http://dbpedia.org/ontology/>
PREFIX dbp: <http://dbpedia.org/property/>
SELECT ?releaseDate WHERE {
  VALUES ?film {
    <http://dbpedia.org/resource/Worst_Case_Scenario_(film)>
  }
  OPTIONAL {
    ?film dbo:releaseDate ?releaseDate
  }
  OPTIONAL {
    ?film dbp:released ?releaseDate
  }
}

There is no country-specific release date for the Netherlands available in DBpedia for 'Worst Case Scenario'. The only available release date is 2008-01-30.

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

You have access to the following knowledge graphs:
dbpedia at https://qlever.cs.uni-freiburg.de/api/dbpedia

You can use the following SPARQL prefixes implicitly in all functions:
dbo: <http://dbpedia.org/ontology/
dbp: <http://dbpedia.org/property/
dbr: <http://dbpedia.org/resource/
dc: <http://purl.org/dc/terms/
foaf: <http://xmlns.com/foaf/0.1/
owl: <http://www.w3.org/2002/07/owl#
prov: <http://www.w3.org/ns/prov#
purl: <http://purl.org/linguistics/gold/
rdf: <http://www.w3.org/1999/02/22-rdf-syntax-ns#
rdfs: <http://www.w3.org/2000/01/rdf-schema#
schema: <http://schema.org/
skos: <http://www.w3.org/2004/02/skos/core#
xsd: <http://www.w3.org/2001/XMLSchema#
geo: <http://www.opengis.net/ont/geosparql#
geosparql: <http://www.opengis.net/ont/geosparql#
gn: <http://www.geonames.org/ontology#
bd: <http://www.bigdata.com/rdf#
hint: <http://www.bigdata.com/queryHints#
wikibase: <http://wikiba.se/ontology#
qb: <http://purl.org/linked-data/cube#
void: <http://rdfs.org/ns/void#

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. Use the functions to search for 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. Use the execute function to get feedback on intermediate queries. You can go back and forth between knowledge graph searches and SPARQL query executions to refine the query.
4. Use the answer or cancel function to finalize your answer and stop the generation process.

Additional rules:
1. Explain your thought process before and after each step and function call.
2. Do not assume or make up any entities or properties without verifying them with the knowledge graphs and functions.
3. 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.
4. 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.
5. 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.
6. For questions with a "True" or "False" answer the SPARQL query should be an ASK query.
7. 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.

[User] When is the movie Worst Case Scenario going to be in cinemas in the Netherlands?

[Assistant]
Let's break down the question:

1. The user is asking about the release date in cinemas (theatrical release) of the movie "Worst Case Scenario" specifically in the Netherlands.
2. I need to identify the correct entity for the movie "Worst Case Scenario" in DBpedia.
3. Then, I need to find properties related to release date, cinema release, or country-specific release, especially for the Netherlands.

First, I'll search for the entity "Worst Case Scenario" in DBpedia.

[Tool]
Top 10 entity alternatives:
1. Worst Case Scenario (dbr:Worst_Case_Scenario)
2. Worst case scenario (dbr:Worst_case_scenario)
3. Worst Case Scenario (album) (<http://dbpedia.org/resource/Worst_Case_Scenario_(album)>)
4. Worst Case Scenario (film) (<http://dbpedia.org/resource/Worst_Case_Scenario_(film)>): Worst Case Scenario was a comedy horror film to be directed by Dutch director Richard Raaphorst.
5. Worst Case Scenario (song) (<http://dbpedia.org/resource/Worst_Case_Scenario_(song)>): "Worst Case Scenario" is the third single by the English indie b...the band's website that it is one of the band's favourite songs.
6. Worst Case Scenarios (dbr:Worst_Case_Scenarios)
7. The Worst Case Scenario (dbr:The_Worst_Case_Scenario)
8. Worst Case Scenario (VOY) (<http://dbpedia.org/resource/Worst_Case_Scenario_(VOY)>)
9. Worst Case Scenario series (dbr:Worst_Case_Scenario_series)
10. Worst Case Scenario (disambiguation) (<http://dbpedia.org/resource/Worst_Case_Scenario_(disambiguation)>)

[Assistant]
The most relevant entity for the movie is "Worst Case Scenario (film)" with the IRI: <http://dbpedia.org/resource/Worst_Case_Scenario_(film)>. The description confirms it is a comedy horror film to be directed by Dutch director Richard Raaphorst.

Next, I need to find properties related to the release date, especially for cinema/theatrical release, and ideally for the Netherlands. I'll search for properties related to "release date" for this entity.

[Tool]
Top 10 property alternatives:
1. release date (dbo:releaseDate): Release date of a Work or another product (eg Aircraft or other MeansOfTransportation, xsd:date
2. released (dbp:released)
3. country (dbp:country)
4. country (dbo:country): The country where the thing is located., country
5. budget ($) (dbo:budget): xsd:double
6. producer (dbp:producer)
7. budget (dbp:budget)
8. name (dbp:name)
9. music (dbp:music)
10. starring (dbp:starring)

No other items found

[Tool]
Got 80 rows and 3 columns, showing the first 10 rows below:
| subject                                                                               | property                                                            | object                                                                   |
| ------------------------------------------------------------------------------------- | ------------------------------------------------------------------- | ------------------------------------------------------------------------ |
| Worst Case Scenario (film) (<http://dbpedia.org/resource/Worst_Case_Scenario_(film)>) | has abstract (dbo:abstract)                                         | Worst Case Scenario was a comedy...utch director Richard Raaphorst. (en) |
| Worst Case Scenario (film) (<http://dbpedia.org/resource/Worst_Case_Scenario_(film)>) | Wikipage page ID (dbo:wikiPageID)                                   | 24408933 (xsd:int)                                                       |
| Worst Case Scenario (film) (<http://dbpedia.org/resource/Worst_Case_Scenario_(film)>) | Wikipage revision ID (dbo:wikiPageRevisionID)                       | 1107934101 (xsd:int)                                                     |
| Worst Case Scenario (film) (<http://dbpedia.org/resource/Worst_Case_Scenario_(film)>) | page length (characters) of wiki page (dbo:wikiPageLength)          | 5497 (xsd:int)                                                           |
| Worst Case Scenario (film) (<http://dbpedia.org/resource/Worst_Case_Scenario_(film)>) | Link from a Wikipage to an external page (dbo:wikiPageExternalLink) | <http://www.gorehoundinc.com/index2.html>                                |
| Worst Case Scenario (film) (<http://dbpedia.org/resource/Worst_Case_Scenario_(film)>) | name (dbp:name)                                                     | Worst Case Scenario (en)                                                 |
| Worst Case Scenario (film) (<http://dbpedia.org/resource/Worst_Case_Scenario_(film)>) | caption (dbp:caption)                                               | Theatrical poster (en)                                                   |
| Worst Case Scenario (film) (<http://dbpedia.org/resource/Worst_Case_Scenario_(film)>) | writer (dbp:writer)                                                 | Bart Oosterhoorn (en)                                                    |
| Worst Case Scenario (film) (<http://dbpedia.org/resource/Worst_Case_Scenario_(film)>) | country (dbo:country)                                               | Cinema of the Netherlands (dbr:Cinema_of_the_Netherlands)                |
| Worst Case Scenario (film) (<http://dbpedia.org/resource/Worst_Case_Scenario_(film)>) | starring (dbp:starring)                                             | Jaap van Otterlo (en)                                                    |
| ...                                                                                | ...                                                                 | ...                                                                      |

[Tool]
Got 1 row and 3 columns:
| subject                                                                               | property                       | object                |
| ------------------------------------------------------------------------------------- | ------------------------------ | --------------------- |
| Worst Case Scenario (film) (<http://dbpedia.org/resource/Worst_Case_Scenario_(film)>) | release date (dbo:releaseDate) | 2008-01-30 (xsd:date) |

[Tool]
Got 1 row and 3 columns:
| subject                                                                               | property                | object                |
| ------------------------------------------------------------------------------------- | ----------------------- | --------------------- |
| Worst Case Scenario (film) (<http://dbpedia.org/resource/Worst_Case_Scenario_(film)>) | released (dbp:released) | 2008-01-30 (xsd:date) |

[Tool]
Got 1 row and 3 columns:
| subject                                                                               | property              | object                                                    |
| ------------------------------------------------------------------------------------- | --------------------- | --------------------------------------------------------- |
| Worst Case Scenario (film) (<http://dbpedia.org/resource/Worst_Case_Scenario_(film)>) | country (dbo:country) | Cinema of the Netherlands (dbr:Cinema_of_the_Netherlands) |

[Assistant]
The movie "Worst Case Scenario (film)" has a release date property (dbo:releaseDate and dbp:released) set to 2008-01-30. The country property is "Cinema of the Netherlands," which suggests that this date is relevant for the Netherlands.

Therefore, the answer is that the movie was (or was planned to be) in cinemas in the Netherlands on 2008-01-30.

Here is the SPARQL query that retrieves this information:

[Tool] Stopped generation process

[User]
Feedback (status=retry):
The SPARQL query failed to execute due to a syntax error. Additionally, the query attempts to filter for the Netherlands by using dbo:country dbr:Cinema_of_the_Netherlands, which is not the correct way to specify a country for a film's release date. Typically, release dates by country are modeled using properties like dbo:releaseDate or dbo:release, sometimes with qualifiers for country. The answer provided is not supported by a successful query execution. Please rework the query to correctly retrieve the release date of 'Worst Case Scenario' in the Netherlands, if available, and ensure the query is syntactically correct and executable.

[Assistant]
Thank you for the feedback. I understand that my previous query had a syntax error and that filtering by country using dbo:country is not the correct way to specify a release date for a specific country. Instead, I should focus on retrieving all available release dates for the film and see if any are specific to the Netherlands.

Step-by-step plan:
1. Retrieve all release date-related properties for the film "Worst Case Scenario (film)".
2. Check if any of these properties are country-specific or have qualifiers for the Netherlands.
3. If not, provide the general release date if available.

First, I will check all properties related to "release" for this film to see if any are country-specific.

[Tool]
Top 10 property alternatives:
1. released (dbp:released)
2. release date (dbo:releaseDate): Release date of a Work or another product (eg Aircraft or other MeansOfTransportation, xsd:date
3. producer (dbp:producer)
4. caption (dbp:caption)
5. name (dbp:name)
6. distributor (dbp:distributor)
7. music (dbp:music)
8. country (dbp:country)
9. country (dbo:country): The country where the thing is located., country
10. language (dbp:language)

No other items found

[Assistant]
The only available properties related to release are dbp:released and dbo:releaseDate, both of which are already known and do not have country qualifiers. There is no evidence of a country-specific release date property for the Netherlands.

Therefore, the best possible answer is to provide the general release date for the film, as no country-specific release date for the Netherlands is available in DBpedia.

Here is a corrected SPARQL query that retrieves all available release dates for the film:

[Tool] Stopped generation process

[User]
Feedback (status=done):
The answer correctly reflects the available data in DBpedia. The SPARQL query retrieves all available release dates for 'Worst Case Scenario' and notes the lack of a country-specific release date for the Netherlands. The query is well-formed, returns the IRI of the film (as required), and uses appropriate properties. No further refinement is necessary.


PREFIX dbp: <http://dbpedia.org/property/>
PREFIX rdfs: <http://www.w3.org/2000/01/rdf-schema#>
PREFIX dbr: <http://dbpedia.org/resource/>
SELECT ?governor ?governorLabel WHERE {
  dbr:Texas dbp:governor ?governor .
  FILTER ( STRLEN( STR( ?governor ) ) > 0 ) OPTIONAL {
    ?governor rdfs:label ?governorLabel .
    FILTER ( lang( ?governorLabel ) = 'en' )
  }
}

Got 1 row and 2 columns:
| governor                      | governorLabel    |
| ----------------------------- | ---------------- |
| Greg Abbott (dbr:Greg_Abbott) | Greg Abbott (en) |

The governor of Texas is Greg Abbott (dbr:Greg_Abbott).

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

You have access to the following knowledge graphs:
dbpedia at https://qlever.cs.uni-freiburg.de/api/dbpedia

You can use the following SPARQL prefixes implicitly in all functions:
dbo: <http://dbpedia.org/ontology/
dbp: <http://dbpedia.org/property/
dbr: <http://dbpedia.org/resource/
dc: <http://purl.org/dc/terms/
foaf: <http://xmlns.com/foaf/0.1/
owl: <http://www.w3.org/2002/07/owl#
prov: <http://www.w3.org/ns/prov#
purl: <http://purl.org/linguistics/gold/
rdf: <http://www.w3.org/1999/02/22-rdf-syntax-ns#
rdfs: <http://www.w3.org/2000/01/rdf-schema#
schema: <http://schema.org/
skos: <http://www.w3.org/2004/02/skos/core#
xsd: <http://www.w3.org/2001/XMLSchema#
geo: <http://www.opengis.net/ont/geosparql#
geosparql: <http://www.opengis.net/ont/geosparql#
gn: <http://www.geonames.org/ontology#
bd: <http://www.bigdata.com/rdf#
hint: <http://www.bigdata.com/queryHints#
wikibase: <http://wikiba.se/ontology#
qb: <http://purl.org/linked-data/cube#
void: <http://rdfs.org/ns/void#

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. Use the functions to search for 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. Use the execute function to get feedback on intermediate queries. You can go back and forth between knowledge graph searches and SPARQL query executions to refine the query.
4. Use the answer or cancel function to finalize your answer and stop the generation process.

Additional rules:
1. Explain your thought process before and after each step and function call.
2. Do not assume or make up any entities or properties without verifying them with the knowledge graphs and functions.
3. 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.
4. 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.
5. 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.
6. For questions with a "True" or "False" answer the SPARQL query should be an ASK query.
7. 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.

[User] Who is the governor of Texas?

[Assistant]
Let's break down the question:

1. The main entity is "Texas", which is a state in the United States.
2. The property of interest is "governor".

First, I will search for the entity "Texas" in DBpedia to get its IRI.

[Tool]
Top 10 entity alternatives:
1. Texas, also known as The Lone Star State (dbr:Texas): Texas (, also locally ) is a state in the South Central region o...e by both area (after Alaska) and population (after California).
2. Jack Burke (boxer), also known as Texas (<http://dbpedia.org/resource/Jack_Burke_(boxer)>): Jack Burke (1869–1913) was a boxer who fought in the longest glo...f his hands and remained bed ridden for 6 weeks after the fight.
3. Geoff Austen, also known as Texas (dbr:Geoff_Austen): Geoff Austen (born 13 October 1953) is a former Australian rules...e role as Peter Moore rose to form and secured a Brownlow medal.
4. Texas (<http://dbpedia.org/resource/Category:Texas>)
5. TEXAS (dbr:TEXAS)
6. Texas, Texas (<http://dbpedia.org/resource/Texas,_Texas>)
7. Laredo, Texas, also known as "The Gateway City" and "The City Under Seven Flags" (<http://dbpedia.org/resource/Laredo,_Texas>)
8. Amarillo, Texas (<http://dbpedia.org/resource/Amarillo,_Texas>): Amarillo ( AM-ə-RIL-oh; Spanish for "yellow") is a city in the U...ty. The estimated population of Amarillo was 199,371 as of 2019.
9. Lubbock, Texas, also known as "Hub City" (<http://dbpedia.org/resource/Lubbock,_Texas>): Lubbock ( LUB-ək)is the 11th-most populous city in the U.S. stat...9, the city is also the 83rd-most populous in the United States.
10. Brownsville, Texas, also known as Chess Capital of Texas (<http://dbpedia.org/resource/Brownsville,_Texas>)

[Assistant]
The correct entity for Texas is dbr:Texas.

Next, I need to find the property that links a U.S. state to its governor. I will search for properties related to "governor" in DBpedia.

[Tool]
Top 10 property alternatives:
1. governor (dbo:governor): person
2. Governor (dbp:governor)
3. governorgeneral (dbp:governorgeneral)
4. name of governor (dbp:nameOfGovernor)
5. governor as of (dbp:governorAsOf)
6. governor title (dbp:governorTitle)
7. Governor start (dbp:governorStart)
8. Governor date (dbp:governorDate)
9. Acting Governor (dbp:actingGovernor)
10. executive governor (dbp:executiveGovernor)

[Assistant]
The most likely properties to use are dbo:governor (ontology property) and dbp:governor (property from infoboxes). The ontology property dbo:governor is preferred for consistency and structure.

Now, I will write a SPARQL query to find the governor of dbr:Texas using dbo:governor, and also try to get the label of the governor for readability.

[Tool] Got no rows and 2 columns

[Assistant]
It appears that the dbo:governor property does not return any results for dbr:Texas. This could mean that the ontology property is not used for this entity, or the data is missing.

Next, I will try the dbp:governor property, which is often used for infobox data in DBpedia.

[Tool]
Got 2 rows and 2 columns:
| governor                      | governorLabel    |
| ----------------------------- | ---------------- |
|  (en)                         |                  |
| Greg Abbott (dbr:Greg_Abbott) | Greg Abbott (en) |

[Assistant]
The query using dbp:governor returns "Greg Abbott" (dbr:Greg_Abbott) as the governor of Texas.

Here is the final SPARQL query and answer.

[Tool] Stopped generation process

[User]
Feedback (status=refine):
The answer is correct and the SPARQL query is close, but the query result includes an empty row, which is not relevant. The query should be refined to filter out empty or null values for the governor. Additionally, it would be helpful to optionally include the label of the governor using rdfs:label in an OPTIONAL clause, as this can make the result more human-readable if needed. The current query otherwise follows the rules, returning the IRI of the governor.

[Assistant]
Thank you for the feedback. To refine the query:

1. I will add a FILTER to exclude empty or null values for the governor.
2. I will include an OPTIONAL clause to retrieve the rdfs:label of the governor (in English) for human readability.

Here is the improved SPARQL query:

```sparql
SELECT ?governor ?governorLabel WHERE {
  dbr:Texas dbp:governor ?governor .
  FILTER(STRLEN(STR(?governor)) > 0)
  OPTIONAL { ?governor rdfs:label ?governorLabel . FILTER (lang(?governorLabel) = 'en') }
}
```

This query will only return non-empty governor values and, if available, their English labels.

Final answer:
The governor of Texas is Greg Abbott (dbr:Greg_Abbott).

[Tool] Stopped generation process

[User]
Feedback (status=done):
The SPARQL query correctly retrieves the current governor of Texas by querying the 'dbp:governor' property of dbr:Texas. It returns the IRI of the governor and optionally retrieves the English label. The answer matches the expected result, and the query follows all required guidelines. No further refinement is necessary.