Namespace Lucene.Net.Facet

Provides faceted indexing and search capabilities. Checkout this and this blog posts for some overview on the facets module as well as source code examples here.

Classes

DrillDownQuery

A for drill-down over facet categories. You should call Add(String, String[]) for every group of categories you want to drill-down over.

NOTE: if you choose to create your own by calling Term(String, String, String[]), it is recommended to wrap it with and set the boost to 0.0f, so that it does not affect the scores of the documents.

@lucene.experimental

DrillSideways

Computes drill down and sideways counts for the provided DrillDownQuery. Drill sideways counts include alternative values/aggregates for the drill-down dimensions so that a dimension does not disappear after the user drills down into it.

Use one of the static search methods to do the search, and then get the hits and facet results from the returned DrillSidewaysResult.

NOTE: this allocates one FacetsCollector for each drill-down, plus one. If your index has high number of facet labels then this will multiply your memory usage. @lucene.experimental

DrillSidewaysResult

Result of a drill sideways search, including the Facets and .

FacetField

Add an instance of this to your for every facet label.

NOTE: you must call Build(Document) before you add the document to .

FacetResult

Counts or aggregates for a single dimension.

Facets

Common base class for all facets implementations.

@lucene.experimental

FacetsCollector

Collects hits for subsequent faceting. Once you've run a search and collect hits into this, instantiate one of the subclasses to do the facet counting. Use the Search utility methods (such as Search(IndexSearcher, Query, Int32, ICollector)) to perform an "ordinary" search but also collect into a Facets.

FacetsCollector.Docs

Used during collection to record matching docs and then return a DocIdSet that contains them.

FacetsCollector.MatchingDocs

Holds the documents that were matched in the . If scores were required, then Scores is not null.

FacetsConfig

Records per-dimension configuration. By default a dimension is flat, single valued and does not require count for the dimension; use the setters in this class to change these settings for each dim.

NOTE: this configuration is not saved into the index, but it's vital, and up to the application to ensure, that at search time the provided FacetsConfig matches what was used during indexing. @lucene.experimental

FacetsConfig.DimConfig

Holds the configuration for one dimension

@lucene.experimental

LabelAndValue

Single label and its value, usually contained in a FacetResult.

MultiFacets

Maps specified dims to provided Facets impls; else, uses the default Facets impl.

RandomSamplingFacetsCollector

Collects hits for subsequent faceting, using sampling if needed. Once you've run a search and collect hits into this, instantiate one of the Facets subclasses to do the facet counting. Note that this collector does not collect the scores of matching docs (i.e. Scores) is null.

If you require the original set of hits, you can call GetOriginalMatchingDocs(). Also, since the counts of the top-facets is based on the sampled set, you can amortize the counts by calling AmortizeFacetCounts(FacetResult, FacetsConfig, Search.IndexSearcher).

TopOrdAndInt32Queue

Keeps highest results, first by largest value, then tie break by smallest ord.

NOTE: This was TopOrdAndIntQueue in Lucene

TopOrdAndInt32Queue.OrdAndValue

Holds a single entry.

TopOrdAndSingleQueue

Keeps highest results, first by largest value, then tie break by smallest ord.

NOTE: This was TopOrdAndFloatQueue in Lucene

TopOrdAndSingleQueue.OrdAndValue

Holds a single entry.