Class BoostingQuery

The BoostingQuery class can be used to effectively demote results that match a given query. Unlike the "NOT" clause, this still selects documents that contain undesirable terms, but reduces their overall score:

    Query balancedQuery = new BoostingQuery(positiveQuery, negativeQuery, 0.01f);

In this scenario the positiveQuery contains the mandatory, desirable criteria which is used to select all matching documents, and the negativeQuery contains the undesirable elements which are simply used to lessen the scores. Documents that match the negativeQuery have their score multiplied by the supplied "boost" parameter, so this should be less than 1 to achieve a demoting effect

This code was originally made available here: [WWW] http://marc.theaimsgroup.com/?l=lucene-user&m=108058407130459&w=2 and is documented here: http://wiki.apache.org/lucene-java/CommunityContributions

Inheritance

System.Object

Lucene.Net.Search.Query

BoostingQuery

Inherited Members

Lucene.Net.Search.Query.Boost

Lucene.Net.Search.Query.ToString()

Lucene.Net.Search.Query.CreateWeight(Lucene.Net.Search.IndexSearcher)

Query.ExtractTerms(ISet<Term>)

Lucene.Net.Search.Query.Clone()

System.Object.Equals(System.Object, System.Object)

System.Object.GetType()

System.Object.MemberwiseClone()

System.Object.ReferenceEquals(System.Object, System.Object)

Namespace: Lucene.Net.Queries

Assembly: Lucene.Net.Queries.dll

Syntax

public class BoostingQuery : Query

Constructors

BoostingQuery(Query, Query, Single)

Declaration

public BoostingQuery(Query match, Query context, float boost)

Parameters

Type	Name	Description
Lucene.Net.Search.Query	match
Lucene.Net.Search.Query	context
System.Single	boost

Methods

Equals(Object)

Declaration

public override bool Equals(object obj)

Parameters

Type	Name	Description
System.Object	obj

Returns

Type	Description
System.Boolean

Overrides

Query.Equals(Object)

GetHashCode()

Declaration

public override int GetHashCode()

Returns

Type	Description
System.Int32

Overrides

Lucene.Net.Search.Query.GetHashCode()

Rewrite(IndexReader)

Declaration

public override Query Rewrite(IndexReader reader)

Parameters

Type	Name	Description
Lucene.Net.Index.IndexReader	reader

Returns

Type	Description
Lucene.Net.Search.Query

Overrides

Lucene.Net.Search.Query.Rewrite(Lucene.Net.Index.IndexReader)

ToString(String)

Declaration

public override string ToString(string field)

Parameters

Type	Name	Description
System.String	field

Returns

Type	Description
System.String

Overrides

Query.ToString(String)