Most common datatypes in DBpedia - database

Question

I need to know which are the most common datatypes in DBpedia. So I am asking a query to Virtuoso like this:
SELECT datatype(?d) (COUNT(?d) as ?dCount)
WHERE
{
?s ?p ?d
}
GROUP BY ?d
ORDER BY DESC(?dCount)
I am not sure if the query is correct and, above all, the transaction timed out. How can I get my answer or reduce my research space to "something relevant"? Or, for example, get anyway my result when the query times out?

Answer 1

The query is not correct.
You must group by the datatype, not the literal value:
SELECT (datatype(?d) as ?dt) (COUNT(?d) as ?dCount)
WHERE
{
?s ?p ?d
FILTER(isLiteral(?d))
}
GROUP BY datatype(?d)
ORDER BY DESC(?dCount)
The query might still timeout.
You could restrict it to data properties of DBpedia, i.e.
SELECT (datatype(?d) as ?dt) (COUNT(*) as ?dCount)
WHERE
{
?p a owl:DatatypeProperty .
?s ?p ?d
}
GROUP BY datatype(?d)
ORDER BY DESC(?dCount)
but you would miss the triples with properties of http://dbpedia.org/property/ namespace.
Alternatives:
load the data into a local more powerful server
simply use the DBpedia ontology although this probably doesn't contain all datatypes used in the instance data