Подсчет в SPARQL

Ok so i have this query

PREFIX rdfs:  

SELECT DISTINCT (COUNT(?instance) AS ?count) WHERE {
?instance a  . 
}

and the result is 286. Cool. Now I want to get the number of ambassadors that have http://dbpedia.org/property/name property. But

PREFIX rdfs:  

SELECT DISTINCT (COUNT(?instance) AS ?count) WHERE {
?instance a  . 
?instance  ?name
}

results in 533 :(. So it is counting more because there are people which have this property one or more times. But how do I get the number of ambassadors that have this property regardless of how many times they have it. Can you do this in a single query?

Thanks.