Package org.apache.lucene.search.join

Class DiversifyingChildrenFloatKnnVectorQuery

java.lang.Object

org.apache.lucene.search.Query

org.apache.lucene.search.KnnFloatVectorQuery

org.apache.lucene.search.join.DiversifyingChildrenFloatKnnVectorQuery

public class DiversifyingChildrenFloatKnnVectorQuery
extends KnnFloatVectorQuery

kNN float vector query that joins matching children vector documents with their parent doc id. The top documents returned are the child document ids and the calculated scores. Here is how to use this in conjunction with ToParentBlockJoinQuery.

   Query knnQuery = new DiversifyingChildrenFloatKnnVectorQuery(fieldName, queryVector, ...);
   // Rewrite executes kNN search and collects nearest children docIds and their scores
   Query rewrittenKnnQuery = searcher.rewrite(knnQuery);
   // Join the scored children docs with their parents and score the parents
   Query childrenToParents = new ToParentBlockJoinQuery(rewrittenKnnQuery, parentsFilter, ScoreMode.MAX);
 

Field Summary

Fields

Modifier and Type	Field	Description
protected String	field

Constructor Summary

Constructors

Constructor	Description
DiversifyingChildrenFloatKnnVectorQuery(String field, float[] query, Query childFilter, int k, BitSetProducer parentsFilter)	Create a ToParentBlockJoinFloatVectorQuery.

Method Summary

Modifier and Type	Method	Description
protected TopDocs	approximateSearch(LeafReaderContext context, Bits acceptDocs, int visitedLimit, KnnCollectorManager knnCollectorManager)
boolean	equals(Object o)
protected TopDocs	exactSearch(LeafReaderContext context, DocIdSetIterator acceptIterator)
String	getField()
Query	getFilter()
int	getK()
protected KnnCollectorManager	getKnnCollectorManager(int k, IndexSearcher searcher)
int	hashCode()
protected TopDocs	mergeLeafResults(TopDocs[] arg0)
Query	rewrite(IndexSearcher arg0)
String	toString(String field)
void	visit(QueryVisitor arg0)

Methods inherited from class org.apache.lucene.search.KnnFloatVectorQuery

getTargetCopy

Methods inherited from class org.apache.lucene.search.Query

classHash, createWeight, rewrite, sameClassAs, toString

Methods inherited from class java.lang.Object

clone, finalize, getClass, notify, notifyAll, wait, wait, wait

Field Detail

field

protected final String field

Constructor Detail

DiversifyingChildrenFloatKnnVectorQuery

public DiversifyingChildrenFloatKnnVectorQuery(String field,
                                               float[] query,
                                               Query childFilter,
                                               int k,
                                               BitSetProducer parentsFilter)

Create a ToParentBlockJoinFloatVectorQuery.

Parameters:

field - the query field

query - the vector query

childFilter - the child filter

k - how many parent documents to return given the matching children

parentsFilter - Filter identifying the parent documents.

Method Detail

exactSearch

protected TopDocs exactSearch(LeafReaderContext context,
                              DocIdSetIterator acceptIterator)
                       throws IOException

Throws:

IOException

getKnnCollectorManager

protected KnnCollectorManager getKnnCollectorManager(int k,
                                                     IndexSearcher searcher)

approximateSearch

protected TopDocs approximateSearch(LeafReaderContext context,
                                    Bits acceptDocs,
                                    int visitedLimit,
                                    KnnCollectorManager knnCollectorManager)
                             throws IOException

Overrides:

approximateSearch in class KnnFloatVectorQuery

Throws:

IOException

toString

public String toString(String field)

Overrides:

toString in class KnnFloatVectorQuery

equals

public boolean equals(Object o)

Overrides:

equals in class KnnFloatVectorQuery

hashCode

public int hashCode()

Overrides:

hashCode in class KnnFloatVectorQuery

rewrite

public Query rewrite(IndexSearcher arg0)
              throws IOException

Overrides:

rewrite in class Query

Throws:

IOException

mergeLeafResults

protected TopDocs mergeLeafResults(TopDocs[] arg0)

visit

public void visit(QueryVisitor arg0)

Specified by:

visit in class Query

getField

public String getField()

getK

public int getK()

getFilter

public Query getFilter()