Parses a SPARQL query or update string into its algebra representation, with blank nodes converted to
variables.
A query is parsed out of quad mode, so that a GRAPH survives as an operation of its own rather than as
the graph component of every pattern below it, which is what lets the GRAPH rules of the passes see it at
all. An update has an algebra only in quad mode, so it gets one, and
userQueryRestrictions!assertUserQueryIsSupported reads the graph of each pattern instead.
Parses a SPARQL query or update string into its algebra representation, with blank nodes converted to variables.
A query is parsed out of quad mode, so that a
GRAPHsurvives as an operation of its own rather than as the graph component of every pattern below it, which is what lets the GRAPH rules of the passes see it at all. An update has an algebra only in quad mode, so it gets one, and userQueryRestrictions!assertUserQueryIsSupported reads the graph of each pattern instead.