org.janusgraph.graphdb.query.index

Class ApproximateIndexSelectionStrategy

java.lang.Object

org.janusgraph.graphdb.query.index.AbstractIndexSelectionStrategy

org.janusgraph.graphdb.query.index.ApproximateIndexSelectionStrategy

All Implemented Interfaces:

IndexSelectionStrategy

public class ApproximateIndexSelectionStrategy
extends AbstractIndexSelectionStrategy

Author:

Florian Grieskamp (Florian.Grieskamp@gdata.de)

Nested Class Summary

Nested classes/interfaces inherited from interface org.janusgraph.graphdb.query.index.IndexSelectionStrategy

IndexSelectionStrategy.SelectedIndexQuery

Field Summary

Fields

Modifier and Type	Field and Description
static String	NAME

Constructor Summary

Constructors

Constructor and Description
ApproximateIndexSelectionStrategy(Configuration config)

Method Summary

Modifier and Type	Method and Description
IndexSelectionStrategy.SelectedIndexQuery	selectIndices(Set<IndexType> rawCandidates, MultiCondition<JanusGraphElement> conditions, Set<Condition> coveredClauses, OrderList orders, IndexSerializer serializer) Iterate over all potential indexes and compute a score based on how many clauses this index covers.

Methods inherited from class org.janusgraph.graphdb.query.index.AbstractIndexSelectionStrategy

addToJointQuery, createIndexCandidate, createIndexRawCandidates, getConditionBasicScore, getIndexTypeScore, selectIndices

Methods inherited from class java.lang.Object

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

Field Detail

NAME

public static final String NAME

See Also:

Constant Field Values

Constructor Detail

ApproximateIndexSelectionStrategy

public ApproximateIndexSelectionStrategy(Configuration config)

Method Detail

selectIndices

public IndexSelectionStrategy.SelectedIndexQuery selectIndices(Set<IndexType> rawCandidates,
                                                               MultiCondition<JanusGraphElement> conditions,
                                                               Set<Condition> coveredClauses,
                                                               OrderList orders,
                                                               IndexSerializer serializer)

Iterate over all potential indexes and compute a score based on how many clauses this index covers. The index with the highest score (as long as it covers at least one additional clause) is picked and added to the joint query for as long as such exist.