Click or drag to resize

FilteredProductOptimiser Class

An Algebra Optimiser which implements the Filtered Product optimisation.
Inheritance Hierarchy

Namespace:  VDS.RDF.Query.Optimisation
Assembly:  dotNetRDF (in dotNetRDF.dll) Version:
public class FilteredProductOptimiser : IAlgebraOptimiser

The FilteredProductOptimiser type exposes the following members.

Public methodFilteredProductOptimiser
Initializes a new instance of the FilteredProductOptimiser class
Public methodEquals
Determines whether the specified object is equal to the current object.
(Inherited from Object.)
Protected methodFinalize
Allows an object to try to free resources and perform other cleanup operations before it is reclaimed by garbage collection.
(Inherited from Object.)
Public methodGetHashCode
Serves as the default hash function.
(Inherited from Object.)
Public methodGetType
Gets the Type of the current instance.
(Inherited from Object.)
Public methodIsApplicable(SparqlQuery)
Returns that this optimiser is applicable to all queries.
Public methodIsApplicable(SparqlUpdateCommandSet)
Returns that this optimiser is applicable to all updates.
Protected methodMemberwiseClone
Creates a shallow copy of the current Object.
(Inherited from Object.)
Public methodOptimise
Optimises the Algebra to use implict joins where applicable.
Public methodToString
Returns a string that represents the current object.
(Inherited from Object.)

A filtered product is implied by any query where there is a product over a join or within a BGP around which there is a Filter which contains variables from both sides of the product. So rather than computing the entire product and then applying the filter we want to push filter application into the product computation.

See Also