Namespace VDS.RDF.Query.Algebra

Classes

AlgebraExtensions

Static Helper class containing extensions used in the Algebra evaluation process.

Ask

Represents the Ask step of Query Evaluation.

AskAnyTriples

Special Algebra Construct for optimising queries of the form ASK WHERE {?s ?p ?o}.

AskBgp

Represents a BGP which is a set of Triple Patterns.

AskUnion

Represents a Union.

BaseArbitraryLengthPathOperator

Abstract Base Class for Arbitrary Length Path Operators.

BaseMultiset

Abstract Base Class for representing Multisets.

BasePathOperator

Abstract Base Class for Path Operators.

BaseSet

Abstract Base Class for implementations of the ISet interface.

Bgp

Represents a BGP which is a set of Triple Patterns.

Bindings

Represents a BINDINGS modifier on a SPARQL Query.

Distinct

Represents a Distinct modifier on a SPARQL Query.

ExistsJoin

Represents a LeftJoin predicated on the existence/non-existence of joinable sets on the RHS for each item on the LHS.

Extend

Represents an Extend operation which is the formal algebraic form of the BIND operation.

Filter

Represents a Filter.

FilteredProduct

Algebra operator which combines a Filter and a Product into a single operation for improved performance and reduced memory usage.

FullTextQuery

Algebra Operator which provides full text query capabilities for a query.

Graph

Represents a GRAPH clause.

GroupBy

Represents a Grouping.

GroupMultiset

Multiset which represents a Grouping of Sets from another Multiset.

Having

Represents a Having Clause.

IdentityFilter

Represents a special case Filter where the Filter restricts a variable to just one value i.e. FILTER(?x = <value>).

IdentityMultiset

Represents the Identity Multiset.

Join

Represents a Join.

LazyBgp

Represents a BGP which is a set of Triple Patterns.

LazyUnion

Represents a Union.

LeftJoin

Represents a LeftJoin predicated on an arbitrary filter expression.

Minus

Represents the Minus join.

Multiset

Represents a Multiset of possible solutions.

NegatedPropertySet

Represents a Negated Property Set in the SPARQL Algebra.

NullMultiset

Represents a Multiset when there are no possible Solutions.

NullOperator

Represents a part of the algebra that has been determined to not return any results in advance and so can be replaced with this operator which always returns null.

OneOrMorePath

Represents a One or More Path (e.g. rdf:type+) in the SPARQL Algebra.

OrderBy

Represents an Order By clause.

ParallelJoin

Represents a Join which will be evaluated in parallel.

ParallelUnion

Represents a Union which will be evaluated in parallel.

PartitionedMultiset

Implementation of a multiset which is suitable for multiple threads to write to in parallel, useful for parallelizing certain operations.

PropertyFunction

Algebra that represents the application of a Property Function.

PropertyPath

Represents an arbitrary property path in the algebra (only used when strict algebra is generated).

Reduced

Represents a Reduced modifier on a SPARQL Query.

SameTermFilter

Represents a special case Filter where the Filter is supposed to restrict a variable to just one value i.e. FILTER(SAMETERM(?x, <value>)).

Select

Represents the Selection step of Query Evaluation.

SelectDistinctGraphs

Special Algebra Construct for optimising queries of the form SELECT DISTINCT ?g WHERE {GRAPH ?g {?s ?p ?o}}.

Service

Represents a Service Clause.

Set

Represents one possible set of values which is a solution to the query.

SetDistinctnessComparer

Comparer for checking whether sets are distinct, check may either be using the entire set or by using only a subset of variables.

SetExtensions

Additional utility methods for ISet.

SingleValueRestrictionFilter

Abstract Base Class for specialised Filters which restrict the value of a variable to a single value.

Slice

Represents the Slice Operation in the SPARQL Algebra.

SubQuery

Represents a sub-query as an Algebra operator (only used when strict algebra is generated).

Table

Represents a fixed set of solutions.

Union

Represents a Union.

VariableRestrictionFilter

Abstract Base Class for specialised Filters which restrict the value of a variable to some values.

ZeroLengthPath

Represents a Zero Length Path in the SPARQL Algebra.

ZeroOrMorePath

Represents a Zero or More Path in the SPARQL Algebra.

Interfaces

IAbstractJoin

Represents an Algebra construct which is an Abstract Join (i.e. any kind of Join over two algebra operators).

IBgp

Represents an Algebra construct which is a BGP.

IExistsJoin

Represents an Algebra construct which is an Exists Join.

IFilter

Represents an Algebra construct which is a Filter.

IJoin

Represents an Algebra construct which is a Join.

ILeftJoin

Represents an Algebra construct which is a Left Join.

ILeviathanAlgebraExtension

Interface to be implemented by extension algebras that can be evaluated by the Leviathan query engine.

IMinus

Represents an Algebra construct which is a Minus.

IPathOperator

Interface for Property Path Operators.

ISet

Interface for Sets which represents a possible solution during SPARQL evaluation.

ISparqlAlgebra

Interface for classes that represent the SPARQL Algebra and are used to evaluate queries.

ITerminalOperator

Marker Interface for SPARQL Algebra constructs which are terminal operators i.e. they contain no inner algebra operators.

IUnaryOperator

Interface for SPARQL Algebra constructs which are unary operators i.e. they apply over a single inner Algebra.

IUnion

Represents an Algebra construct which is a Union.