EXISTStential Aspects of SPARQL
نویسندگان
چکیده
The SPARQL 1.1 Query Language [1] permits patterns inside FILTER expressions using the EXISTS construct, specified by using substitution. Substitution destroys some of the aspects of SPARQL that make it suitable as a data access language. As well, substitution causes problems in the SPARQL algebra and produces counterintuitive results. Fixing the problems with EXISTS is best done with a completely different definition that does not use substitution at all.
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