DBpedia Query Skill

When to Use This Skill

Use this skill when users want to:

• Query DBpedia using natural language
• Ask questions about people, places, movies, books, organizations, etc.
• Get structured data from Wikipedia via DBpedia
• Create visualizations of DBpedia query results
• Generate HTML reports from SPARQL queries

Core Capabilities

✅ Natural Language to SPARQL: Convert user questions into valid SPARQL queries

✅ Query Execution: Execute queries against DBpedia endpoint

✅ HTML Generation: Create beautiful, interactive HTML result pages

✅ Multiple Output Formats: JSON, Markdown tables, or HTML

✅ Error Handling: Graceful handling of malformed queries or no results

DBpedia Endpoint

SPARQL Endpoint: https://dbpedia.org/sparql

Format: JSON results (format=json)

Method: HTTP GET with URL-encoded query

Common DBpedia Prefixes

PREFIX dbo: <http://dbpedia.org/ontology/>
PREFIX dbr: <http://dbpedia.org/resource/>
PREFIX dbp: <http://dbpedia.org/property/>
PREFIX rdfs: <http://www.w3.org/2000/01/rdf-schema#>
PREFIX rdf: <http://www.w3.org/1999/02/22-rdf-syntax-ns#>
PREFIX foaf: <http://xmlns.com/foaf/0.1/>
PREFIX dct: <http://purl.org/dc/terms/>

Query Conversion Workflow

When a user provides a natural language prompt:

1. Analyze the Question

• Identify the subject (who/what is being asked about)
• Identify the predicate (what information is requested)
• Determine if filtering, sorting, or limiting is needed

2. Map to DBpedia Properties

Common mappings:

• "directed by" → dbo:director
• "release date" → dbp:date or dbo:releaseDate
• "budget" → dbo:budget
• "born in" → dbo:birthPlace
• "population" → dbo:populationTotal
• "capital of" → dbo:capital
• "written by" → dbo:author
• "starring" → dbo:starring

3. Construct SPARQL Query

Template:

PREFIX dbo: <http://dbpedia.org/ontology/>
PREFIX dbr: <http://dbpedia.org/resource/>
PREFIX rdfs: <http://www.w3.org/2000/01/rdf-schema#>

SELECT DISTINCT ?variable ?label
WHERE {
  ?variable <predicate> <object> ;
           rdfs:label ?label .
  FILTER(LANG(?label) = 'en')
}
ORDER BY <sort_criteria>
LIMIT <number>

4. Execute Query

Use curl to execute against DBpedia:

curl -s -G "https://dbpedia.org/sparql" \
  --data-urlencode "query=<SPARQL_QUERY>" \
  --data-urlencode "format=json"

5. Generate Output

Options:

• JSON: Raw query results
• Markdown Table: Formatted for terminal display
• HTML Page: Interactive, styled results page

Example Query Patterns

Pattern 1: Films by Director

User: "Show me movies directed by Christopher Nolan"

SPARQL:

PREFIX dbo: <http://dbpedia.org/ontology/>
PREFIX dbr: <http://dbpedia.org/resource/>
PREFIX rdfs: <http://www.w3.org/2000/01/rdf-schema#>

SELECT DISTINCT ?film ?title ?releaseDate
WHERE {
  ?film dbo:director dbr:Christopher_Nolan ;
        a dbo:Film ;
        rdfs:label ?title .
  OPTIONAL { ?film dbo:releaseDate ?releaseDate }
  FILTER(LANG(?title) = 'en')
}
ORDER BY DESC(?releaseDate)

Pattern 2: Population Queries

User: "What are the 10 most populous cities in France?"

SPARQL:

PREFIX dbo: <http://dbpedia.org/ontology/>
PREFIX dbr: <http://dbpedia.org/resource/>
PREFIX rdfs: <http://www.w3.org/2000/01/rdf-schema#>

SELECT ?city ?name ?population
WHERE {
  ?city dbo:country dbr:France ;
        a dbo:City ;
        rdfs:label ?name ;
        dbo:populationTotal ?population .
  FILTER(LANG(?name) = 'en')
}
ORDER BY DESC(?population)
LIMIT 10

Pattern 3: Person Information

User: "Tell me about Albert Einstein - when was he born and where?"

SPARQL:

PREFIX dbo: <http://dbpedia.org/ontology/>
PREFIX dbr: <http://dbpedia.org/resource/>
PREFIX rdfs: <http://www.w3.org/2000/01/rdf-schema#>

SELECT ?birthDate ?birthPlace ?placeLabel
WHERE {
  dbr:Albert_Einstein dbo:birthDate ?birthDate ;
                      dbo:birthPlace ?birthPlace .
  ?birthPlace rdfs:label ?placeLabel .
  FILTER(LANG(?placeLabel) = 'en')
}

HTML Template Generation

When generating HTML results:

Required Elements

1. Title: Question or query description
2. Statistics: Number of results, query execution time
3. Table: Results with hyperlinked DBpedia URIs
4. SPARQL Query Display: Show the executed query
5. Footer: Link to DBpedia, data source attribution

Styling Guidelines

• Use gradient backgrounds
• Responsive design (mobile-friendly)
• Hover effects on table rows
• Hyperlink all DBpedia resources
• Color-code different data types
• Include icons for visual appeal

HTML Template Structure

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>[Query Description] - DBpedia</title>
    <style>
        /* Modern, responsive styling */
        /* Gradient backgrounds */
        /* Hover effects */
        /* Mobile-first design */
    </style>
</head>
<body>
    <div class="container">
        <h1>[Question/Title]</h1>
        <div class="stats">[Results count]</div>
        <table>[Results]</table>
        <div class="sparql-query">[Query code]</div>
        <div class="footer">[Attribution]</div>
    </div>
</body>
</html>

Error Handling

No Results

If query returns 0 results:

• Inform user clearly
• Suggest alternative phrasings
• Check for typos in entity names

Query Errors

If SPARQL syntax error:

• Display error message
• Show attempted query
• Offer to reformulate

Timeout

If query times out:

• Add LIMIT clause
• Simplify query complexity
• Suggest narrowing criteria

Output Preferences

Always ask the user:

"Would you like the results as:
1. JSON (raw data)
2. Markdown table (terminal display)
3. HTML page (interactive visualization)"

Best Practices

1. Always use DISTINCT: Avoid duplicate results
2. Filter by language: Use FILTER(LANG(?label) = 'en')
3. Add LIMIT: Default to LIMIT 100 unless specified
4. Use OPTIONAL: For properties that may not exist
5. Order results: Make results meaningful with ORDER BY
6. Hyperlink in HTML: All DBpedia URIs should be clickable

Example Session

User: "List books written by J.K. Rowling with publication dates"

Assistant:

"I'll query DBpedia for books authored by J.K. Rowling.

Executing SPARQL query against DBpedia endpoint..."

[Constructs and executes query]

"Found 15 books! Would you like the results as:

1. JSON
2. Markdown table
3. HTML page"

User: "HTML page"

Assistant:

[Generates beautiful HTML page with results]

"✓ HTML page generated and saved to: ./jk_rowling_books.html

✓ 15 books found with publication dates"

Scope

This skill handles:

• Queries about entities in DBpedia
• Structured data extraction
• Result formatting and visualization

This skill does NOT handle:

• Text search (use DBpedia Lookup API instead)
• Data modification (read-only queries)
• Real-time data (DBpedia updates periodically)

Version: 1.0.0

Endpoint: https://dbpedia.org/sparql

Data Source: DBpedia (Wikipedia structured data)