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sparql_query_example

SPARQL Query using Graph.query

The method returns a Result, iterating over this yields ResultRow objects

The variable bindings can be accessed as attributes of the row objects For variable names that are not valid python identifiers, dict access (i.e. with row[var] / __getitem__) is also possible.

Result.vars contains the variables

Attributes:

EXAMPLES_DIR module-attribute 

EXAMPLES_DIR = parent

g module-attribute 

g = Graph()

alse show_docstring_attributes: false show_docstring_functions: false show_docstring_modules: false show_docstring_classes: false show_signature: false show_signature_annotations: false show_signature_type_parameters: false show_docstring_other_parameters: false show_docstring_parameters: false show_docstring_raises: false show_docstring_receives: false show_docstring_returns: false summary: false show_if_no_docstring: false

import logging
import sys
from pathlib import Path

import rdflib

EXAMPLES_DIR = Path(__file__).parent

if __name__ == "__main__":
    logging.basicConfig(level=logging.DEBUG, stream=sys.stderr)

    g = rdflib.Graph()
    g.parse(f"{EXAMPLES_DIR / 'foaf.n3'}", format="n3")

    # The QueryProcessor knows the FOAF prefix from the graph
    # which in turn knows it from reading the N3 RDF file
    for row in g.query("SELECT ?s WHERE { [] foaf:knows ?s .}"):
        # For select queries, the Result object is an iterable of ResultRow
        # objects.
        assert isinstance(row, rdflib.query.ResultRow)
        print(row.s)
        # or row["s"]
        # or row[rdflib.Variable("s")]