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% Generated by roxygen2: do not edit by hand
% Please edit documentation in R/rdf_query.R
\name{rdf_query}
\alias{rdf_query}
\title{Perform a SPARQL Query}
\usage{
rdf_query(rdf, query, data.frame = TRUE, ...)
}
\arguments{
\item{rdf}{an rdf object (e.g. from \code{\link{rdf_parse}})}
\item{query}{a SPARQL query, as text string}
\item{data.frame}{logical, should the results be returned as a data.frame?}
\item{...}{additional arguments to a redland initialize-Query}
}
\value{
a data.frame of all query results (default.) Columns will
be named according to variable names in the SPARQL query. Returned
object values will be coerced to match the corresponding R type
to any associated datatype URI, if provided. If a column would
result in mixed classes (e.g. strings and numerics), all types
in the column will be coerced to character strings. If \code{data.frame}
is false, results will be returned as a list with each element
typed by its data URI.
}
\description{
Perform a SPARQL Query
}
\examples{
doc <- system.file("extdata", "dc.rdf", package="redland")
sparql <-
'PREFIX dc: <http://purl.org/dc/elements/1.1/>
SELECT ?a ?c
WHERE { ?a dc:creator ?c . }'
rdf <- rdf_parse(doc)
rdf_query(rdf, sparql)
}
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