MAX - SPARQLqueries

Understanding MAX

The MAX aggregate function returns the largest value from a set of values. It works with numbers (highest value), dates (most recent), and strings (alphabetically last).

Syntax	Description	Example Result
`MAX(?value)`	Largest value overall	Single maximum
`MAX(?value) ... GROUP BY ?category`	Largest per group	One max per category
`MAX(?date)`	Most recent date	Last chronologically

Finding Global Maximums

Largest Country by Area

Run ↗

SELECT (MAX(?area) AS ?maxArea)
WHERE {
  ?country wdt:P31 wd:Q6256 ;
           wdt:P2046 ?area .
}

Aggregate Returns: Russia's area (~17.1 million km²)

Highest Elevation Point

Run ↗

SELECT (MAX(?elevation) AS ?highestPoint)
WHERE {
  ?place wdt:P31 wd:Q8502 ;
         wdt:P2044 ?elevation .
}

Aggregate Returns: Mount Everest (8,848 m)

Most Recently Founded University

Run ↗

SELECT (MAX(?founded) AS ?latestFounding)
WHERE {
  ?uni wdt:P31 wd:Q3918 ;
       wdt:P571 ?founded .
}

Aggregate MAX on dates finds the most recent

MAX with GROUP BY

Combining MAX with GROUP BY finds the maximum value within each category, enabling comparisons across different groups.

Largest City per Country

Run ↗

SELECT ?country ?countryLabel (MAX(?population) AS ?largestCity)
WHERE {
  ?city wdt:P31 wd:Q515 ;
        wdt:P17 ?country ;
        wdt:P1082 ?population .
  SERVICE wikibase:label {
    bd:serviceParam wikibase:language "en" .
  }
}
GROUP BY ?country ?countryLabel
ORDER BY DESC(?largestCity)
LIMIT 20

Aggregate One maximum per country

Latest Birth Year per Profession

Run ↗

SELECT ?occupation ?occupationLabel (MAX(YEAR(?birth)) AS ?latestBirth)
WHERE {
  VALUES ?occupation { wd:Q36180 wd:Q82955 wd:Q1028181 wd:Q593644 }
  ?person wdt:P31 wd:Q5 ;
          wdt:P106 ?occupation ;
          wdt:P569 ?birth .
  SERVICE wikibase:label {
    bd:serviceParam wikibase:language "en" .
  }
}
GROUP BY ?occupation ?occupationLabel
ORDER BY DESC(?latestBirth)

Aggregate Compare: writer, politician, painter, chemist

Longest River per Continent

Run ↗

SELECT ?continent ?continentLabel (MAX(?length) AS ?longestRiver)
WHERE {
  ?river wdt:P31 wd:Q4022 ;
         wdt:P2043 ?length ;
         wdt:P30 ?continent .
  SERVICE wikibase:label {
    bd:serviceParam wikibase:language "en" .
  }
}
GROUP BY ?continent ?continentLabel
ORDER BY DESC(?longestRiver)

Aggregate Geographic comparison across continents

Finding the Item with Maximum Value

Often you want to find which item has the maximum value, not just what the maximum is. This requires a subquery pattern.

Which Country Has Largest Area?

Run ↗

SELECT ?country ?countryLabel ?area
WHERE {
  ?country wdt:P31 wd:Q6256 ;
           wdt:P2046 ?area .
  {
    SELECT (MAX(?a) AS ?maxArea)
    WHERE {
      ?c wdt:P31 wd:Q6256 ;
         wdt:P2046 ?a .
    }
  }
  FILTER(?area = ?maxArea)
  SERVICE wikibase:label {
    bd:serviceParam wikibase:language "en" .
  }
}

Aggregate Subquery pattern to get the actual item

Youngest Person in Each Profession

Run ↗

SELECT ?occupation ?occupationLabel ?person ?personLabel ?birth
WHERE {
  VALUES ?occupation { wd:Q36180 wd:Q82955 wd:Q1028181 }
  ?person wdt:P31 wd:Q5 ;
          wdt:P106 ?occupation ;
          wdt:P569 ?birth .
  {
    SELECT ?occupation (MAX(?b) AS ?maxBirth)
    WHERE {
      VALUES ?occupation { wd:Q36180 wd:Q82955 wd:Q1028181 }
      ?p wdt:P106 ?occupation ;
         wdt:P569 ?b .
    }
    GROUP BY ?occupation
  }
  FILTER(?birth = ?maxBirth)
  SERVICE wikibase:label {
    bd:serviceParam wikibase:language "en" .
  }
}

Aggregate Per-group maximum with item details

MAX vs ORDER BY DESC + LIMIT 1

For finding a single maximum, ORDER BY DESC ... LIMIT 1 is often simpler. Use MAX when you need the value in an aggregate context or with GROUP BY.

Alternative: ORDER BY DESC for Maximum

Run ↗

SELECT ?country ?countryLabel ?area
WHERE {
  ?country wdt:P31 wd:Q6256 ;
           wdt:P2046 ?area .
  SERVICE wikibase:label {
    bd:serviceParam wikibase:language "en" .
  }
}
ORDER BY DESC(?area)
LIMIT 1

Aggregate Simpler for single maximum with item details

Combining MIN and MAX

You can use both MIN and MAX in the same query to find ranges or compare extremes.

Population Range per Country

Run ↗

SELECT ?country ?countryLabel
       (MIN(?pop) AS ?smallestCity)
       (MAX(?pop) AS ?largestCity)
       (MAX(?pop) - MIN(?pop) AS ?range)
WHERE {
  ?city wdt:P31 wd:Q515 ;
        wdt:P17 ?country ;
        wdt:P1082 ?pop .
  SERVICE wikibase:label {
    bd:serviceParam wikibase:language "en" .
  }
}
GROUP BY ?country ?countryLabel
ORDER BY DESC(?range)
LIMIT 10

Aggregate Countries with greatest city size disparity