select distinct * where{
<http://www.shujuhai.cn/knowledgeGraph/Property/29c9d91719744b7e9c1172c3d63adb7a> ?p ?o.
<http://www.shujuhai.cn/knowledgeGraph/Property/29c9d91719744b7e9c1172c3d63adb7a> <http://www.w3.org/2000/01/rdf-schema#label> ?s_lable.
?p <http://www.w3.org/2000/01/rdf-schema#label> ?p_lable.
?o <http://www.w3.org/2000/01/rdf-schema#label> ?o_lable.
FILTER (isIRI(?o))
}
SPARQL查询问题,根据主语查询时在结果集中如何加入已知主语,现在查询结果是主语列为空。