Class GraphPattern

Class for representing Graph Patterns in Sparql Queries.

Inheritance

System.Object

GraphPattern

Inherited Members

object.Equals(object)

object.Equals(object, object)

object.GetHashCode()

object.GetType()

object.MemberwiseClone()

object.ReferenceEquals(object, object)

Namespace: VDS.RDF.Query.Patterns

Assembly: dotNetRdf.dll

Syntax

public class GraphPattern

Constructors

GraphPattern()

Creates a new Graph Pattern.

Declaration

public GraphPattern()

Properties

ChildGraphPatterns

Gets the Child Graph Patterns of this Pattern.

Declaration

public List<GraphPattern> ChildGraphPatterns { get; }

Property Value

Type	Description
System.Collections.Generic.List<T><GraphPattern>

Filter

Gets/Sets the FILTER that applies to this Graph Pattern.

Declaration

public ISparqlFilter Filter { get; }

Property Value

Type	Description
ISparqlFilter

GraphSpecifier

Gets/Sets the Graph Specifier that applies to this Graph Pattern.

Declaration

public IToken GraphSpecifier { get; }

Property Value

Type	Description
IToken

Remarks

This property is also used internally for SERVICE specifiers to save adding an additional property unnecessarily.

HasChildGraphPatterns

Checks whether this Pattern has any Child Graph Patterns.

Declaration

public bool HasChildGraphPatterns { get; }

Property Value

Type	Description
System.Boolean

HasInlineData

Gets whether this Graph Pattern contains an Inline Data block (VALUES clause).

Declaration

public bool HasInlineData { get; }

Property Value

Type	Description
System.Boolean

HasModifier

Determines whether the Graph Pattern has any kind of Modifier (GRAPH, MINUS, OPTIONAL etc) applied.

Declaration

public bool HasModifier { get; }

Property Value

Type	Description
System.Boolean

InlineData

Gets the inline data (VALUES block if any).

Declaration

public BindingsPattern InlineData { get; }

Property Value

Type	Description
BindingsPattern

IsEmpty

Gets whether this is an empty Graph Pattern.

Declaration

public bool IsEmpty { get; }

Property Value

Type	Description
System.Boolean

IsExists

Gets/Sets whether the Graph Pattern is an EXISTS clause.

Declaration

public bool IsExists { get; }

Property Value

Type	Description
System.Boolean

IsFiltered

Gets/Sets whether the Graph Pattern is Filtered.

Declaration

public bool IsFiltered { get; }

Property Value

Type	Description
System.Boolean

IsGraph

Gets/Sets whether the Graph Pattern operates on a specific Graph.

Declaration

public bool IsGraph { get; }

Property Value

Type	Description
System.Boolean

IsMinus

Gets/Sets whether the Graph Pattern is a MINUS clause.

Declaration

public bool IsMinus { get; }

Property Value

Type	Description
System.Boolean

IsNotExists

Gets/Sets whether the Graph Pattern is a NOT EXISTS clause.

Declaration

public bool IsNotExists { get; }

Property Value

Type	Description
System.Boolean

IsOptimised

Gets whether Optimisation has been applied to this query.

Declaration

public bool IsOptimised { get; }

Property Value

Type	Description
System.Boolean

Remarks

This only indicates that an Optimiser has been applied to the Pattern. You can always reoptimise by calling the Optimise() method with an optimiser of your choice on the query to which this Pattern belongs.

IsOptional

Gets/Sets whether the Graph Pattern is Optional.

Declaration

public bool IsOptional { get; }

Property Value

Type	Description
System.Boolean

IsService

Gets/Sets whether the Graph Pattern is a SERVICE clause.

Declaration

public bool IsService { get; }

Property Value

Type	Description
System.Boolean

IsSilent

Gets whether Evaluation Errors in this Graph Pattern are suppressed (currently only valid with SERVICE).

Declaration

public bool IsSilent { get; }

Property Value

Type	Description
System.Boolean

IsSubQuery

Gets whether this Graph Pattern is a Sub-query which can be simplified.

Declaration

public bool IsSubQuery { get; }

Property Value

Type	Description
System.Boolean

IsUnion

Gets/Sets whether the Graph Pattern is a Union of its Child Graph Patterns.

Declaration

public bool IsUnion { get; }

Property Value

Type	Description
System.Boolean

TriplePatterns

Gets the Triple Patterns in this Pattern.

Declaration

public List<ITriplePattern> TriplePatterns { get; }

Property Value

Type	Description
System.Collections.Generic.List<T><ITriplePattern>

UnplacedAssignments

Gets the enumeration of LET assignments that are in this Graph Pattern which will be placed appropriately later.

Declaration

public IEnumerable<IAssignmentPattern> UnplacedAssignments { get; }

Property Value

Type	Description
System.Collections.Generic.IEnumerable<T><IAssignmentPattern>

UnplacedFilters

Gets the enumeration of Filters that apply to this Graph Pattern which will have yet to be placed within the Graph Pattern.

Declaration

public IEnumerable<ISparqlFilter> UnplacedFilters { get; }

Property Value

Type	Description
System.Collections.Generic.IEnumerable<T><ISparqlFilter>

UsesDefaultDataset

Gets whether the Graph Pattern uses the Default Dataset.

Declaration

public bool UsesDefaultDataset { get; }

Property Value

Type	Description
System.Boolean

Remarks

Graph Patterns generally use the Default Dataset unless they are a GRAPH pattern or they contain a Triple Pattern, child Graph Pattern or a FILTER/BIND which does not use the default dataset.

Variables

Gets the Variables used in the Pattern.

Declaration

public IEnumerable<string> Variables { get; }

Property Value

Type	Description
System.Collections.Generic.IEnumerable<T><string>

Methods

AddInlineData(BindingsPattern)

Adds inline data to a Graph Pattern respecting any BGP breaks.

Declaration

public void AddInlineData(BindingsPattern data)

Parameters

Type	Name	Description
BindingsPattern	data

AddTriplePattern(ITriplePattern)

Adds a Triple Pattern to the Graph Pattern respecting any BGP breaks.

Declaration

public void AddTriplePattern(ITriplePattern p)

Parameters

Type	Name	Description
ITriplePattern	p	Triple Pattern.

InsertAssignment(IAssignmentPattern, int)

Inserts an Assignment at a given position.

Declaration

public void InsertAssignment(IAssignmentPattern assignment, int i)

Parameters

Type	Name	Description
IAssignmentPattern	assignment	Assignment.
int	i	Position to insert at.

Remarks

Intended for use by Query Optimisers.

InsertFilter(ISparqlFilter, int)

Inserts a Filter at a given position.

Declaration

public void InsertFilter(ISparqlFilter filter, int i)

Parameters

Type	Name	Description
ISparqlFilter	filter	Filter.
int	i	Position to insert at.

Remarks

Intended for use by Query Optimisers.

Optimise()

Optimises the Graph Pattern using the default query optimiser.

Declaration

public void Optimise()

Optimise(IQueryOptimiser, IEnumerable<string>)

Optimises the Graph Pattern using the given optimiser and with the given variables.

Declaration

public void Optimise(IQueryOptimiser optimiser, IEnumerable<string> vars)

Parameters

Type	Name	Description
IQueryOptimiser	optimiser	Query Optimiser.
System.Collections.Generic.IEnumerable<T><string>	vars	Variables.

Remarks

Important: If a Pattern has already been optimized then calling this again is a no-op.

For finer grained control of what gets optimized you can use QueryOptimisation or QueryOptimisation to disable automatic optimisation and then manually call this method as necessary.

The vars parameter contains Variables mentioned in the parent Graph Pattern (if any) that can be used to guide optimisation of child graph patterns.

Optimise(IQueryOptimiser)

Optimises the Graph Pattern using the given optimiser.

Declaration

public void Optimise(IQueryOptimiser optimiser)

Parameters

Type	Name	Description
IQueryOptimiser	optimiser	Query Optimiser.

Remarks

Important: If a Pattern has already been optimized then calling this again is a no-op.

For finer grained control of what gets optimized you can use QueryOptimisation or QueryOptimisation to disable automatic optimisation and then manually call this method as necessary.

SwapTriplePatterns(int, int)

Swaps the position of the two given Triple Patterns.

Declaration

public void SwapTriplePatterns(int i, int j)

Parameters

Type	Name	Description
int	i	First Position.
int	j	Second Position.

Remarks

Intended for use by Query Optimisers.

ToAlgebra()

Gets the Algebra representation of the Graph Pattern.

Declaration

public ISparqlAlgebra ToAlgebra()

Returns

Type	Description
ISparqlAlgebra

ToString()

Gets the String representation of the Graph Pattern.

Declaration

public override string ToString()

Returns

Type	Description
string

Overrides

object.ToString()

Extension Methods

Extensions.ToSafeString(object)

Extensions.AsEnumerable<T>(T)