Module org.apache.jena.arq

Package org.apache.jena.sparql.engine.optimizer.reorder

Class ReorderFixed

java.lang.Object

org.apache.jena.sparql.engine.optimizer.reorder.ReorderTransformationSubstitution

org.apache.jena.sparql.engine.optimizer.reorder.ReorderFixed

All Implemented Interfaces:

ReorderTransformation

public class ReorderFixed
extends ReorderTransformationSubstitution

Fixed scheme for choosing based on the triple patterns, without looking at the data. It gives a weight to a triple, with more grounded terms being considered better. It weights against rdf:type because that can be very unselective (e.g. ?x rdf:type rdf:Resource)

Field Summary

Fields

Modifier and Type	Field	Description
static final int	MultiTermSampleSize	The number of triples used for the base scale

Fields inherited from class org.apache.jena.sparql.engine.optimizer.reorder.ReorderTransformationSubstitution

log

Constructor Summary

Constructors

Constructor	Description
ReorderFixed()

Method Summary

Modifier and Type	Method	Description
double	weight(PatternTriple pt)

Methods inherited from class org.apache.jena.sparql.engine.optimizer.reorder.ReorderTransformationSubstitution

reorder, reorderIndexes

Methods inherited from class java.lang.Object

equals, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Details

MultiTermSampleSize

public static final int MultiTermSampleSize

The number of triples used for the base scale

See Also:

• Constant Field Values

Constructor Details

ReorderFixed

public ReorderFixed()

Method Details

weight

public double weight(PatternTriple pt)