Last post I spent showing directions for optimizing SPARQL-DL in general. Now I would like to touch a more particular case of SPARQL-DL queries, namely those that contain class/property variables in ABox part of the query. I call down-monotonic all the class/property variables ?x that occur in either Type(•,?x), or PropertyValue(•,?x,•) atom. For these variables we can use class/property hi ... Continue reading