Class LazyUnion

Represents a Union.

Inheritance

object

LazyUnion

Implements

IUnion

IAbstractJoin

ISparqlAlgebra

IVisitable

IProcessable

Inherited Members

object.Equals(object)

object.Equals(object, object)

object.GetHashCode()

object.GetType()

object.MemberwiseClone()

object.ReferenceEquals(object, object)

Namespace: VDS.RDF.Query.Algebra

Assembly: dotNetRdf.dll

Syntax

public class LazyUnion : IUnion, IAbstractJoin, ISparqlAlgebra, IVisitable, IProcessable

Remarks

A Lazy Union differs from a standard Union in that if it finds sufficient solutions on the LHS it has no need to evaluate the RHS.

Constructors

LazyUnion(ISparqlAlgebra, ISparqlAlgebra)

Creates a new Lazy Union.

Declaration

public LazyUnion(ISparqlAlgebra lhs, ISparqlAlgebra rhs)

Parameters

Type	Name	Description
ISparqlAlgebra	lhs	LHS Pattern.
ISparqlAlgebra	rhs	RHS Pattern.

LazyUnion(ISparqlAlgebra, ISparqlAlgebra, int)

Creates a new Lazy Union.

Declaration

public LazyUnion(ISparqlAlgebra lhs, ISparqlAlgebra rhs, int requiredResults)

Parameters

Type	Name	Description
ISparqlAlgebra	lhs	LHS Pattern.
ISparqlAlgebra	rhs	RHS Pattern.
int	requiredResults	The number of results that the Union should attempt to return.

Properties

FixedVariables

Gets the enumeration of fixed variables in the algebra i.e. variables that are guaranteed to have a bound value.

Declaration

public IEnumerable<string> FixedVariables { get; }

Property Value

Type	Description
IEnumerable<string>

FloatingVariables

Gets the enumeration of floating variables in the algebra i.e. variables that are not guaranteed to have a bound value.

Declaration

public IEnumerable<string> FloatingVariables { get; }

Property Value

Type	Description
IEnumerable<string>

Lhs

Gets the LHS of the Join.

Declaration

public ISparqlAlgebra Lhs { get; }

Property Value

Type	Description
ISparqlAlgebra

RequiredResults

Get/set the number of results the union should attempt to return.

Declaration

public int RequiredResults { get; }

Property Value

Type	Description
int

Rhs

Gets the RHS of the Join.

Declaration

public ISparqlAlgebra Rhs { get; }

Property Value

Type	Description
ISparqlAlgebra

Variables

Gets the Variables used in the Algebra.

Declaration

public IEnumerable<string> Variables { get; }

Property Value

Type	Description
IEnumerable<string>

Methods

Accept<T>(ISparqlAlgebraVisitor<T>)

Accept a simple algebra visitor.

Declaration

public T Accept<T>(ISparqlAlgebraVisitor<T> visitor)

Parameters

Type	Name	Description
ISparqlAlgebraVisitor<T>	visitor	The visitor implementation.

Returns

Type	Description
T

Type Parameters

Name	Description
T	The type returned by the Visit methods of the visitor.

Accept<TResult, TContext>(ISparqlQueryAlgebraProcessor<TResult, TContext>, TContext)

Called by an algebra visitor to process an item by invoking the appropriate method on the processor passed in.

Declaration

public TResult Accept<TResult, TContext>(ISparqlQueryAlgebraProcessor<TResult, TContext> processor, TContext context)

Parameters

Type	Name	Description
ISparqlQueryAlgebraProcessor<TResult, TContext>	processor	The processor to invoke.
TContext	context	The context to pass to the processor.

Returns

Type	Description
TResult	The result of invoking the processor method.

Type Parameters

Name	Description
TResult	The type of result returned by the processor.
TContext	The type of the context object to be provided to the processor.

Evaluate(SparqlEvaluationContext)

Evaluates the Lazy Union.

Declaration

public BaseMultiset Evaluate(SparqlEvaluationContext context)

Parameters

Type	Name	Description
SparqlEvaluationContext	context	Evaluation Context.

Returns

Type	Description
BaseMultiset

ToGraphPattern()

Converts the Union back to Graph Patterns.

Declaration

public GraphPattern ToGraphPattern()

Returns

Type	Description
GraphPattern

ToQuery()

Converts the Algebra back to a SPARQL Query.

Declaration

public SparqlQuery ToQuery()

Returns

Type	Description
SparqlQuery

ToString()

Gets the String representation of the Algebra.

Declaration

public override string ToString()

Returns

Type	Description
string

Overrides

object.ToString()

Transform(IAlgebraOptimiser)

Transforms both sides of the Join using the given Optimiser.

Declaration

public ISparqlAlgebra Transform(IAlgebraOptimiser optimiser)

Parameters

Type	Name	Description
IAlgebraOptimiser	optimiser	Optimser.

Returns

Type	Description
ISparqlAlgebra

TransformLhs(IAlgebraOptimiser)

Transforms the LHS of the Join using the given Optimiser.

Declaration

public ISparqlAlgebra TransformLhs(IAlgebraOptimiser optimiser)

Parameters

Type	Name	Description
IAlgebraOptimiser	optimiser	Optimser.

Returns

Type	Description
ISparqlAlgebra

TransformRhs(IAlgebraOptimiser)

Transforms the RHS of the Join using the given Optimiser.

Declaration

public ISparqlAlgebra TransformRhs(IAlgebraOptimiser optimiser)

Parameters

Type	Name	Description
IAlgebraOptimiser	optimiser	Optimser.

Returns

Type	Description
ISparqlAlgebra

Implements

IUnion

IAbstractJoin

ISparqlAlgebra

IVisitable

IProcessable

Extension Methods

Extensions.ToSafeString(object)

Extensions.AsEnumerable<T>(T)