Field Facet Stage

Configuration

The Field Facet query pipeline stage is used to add a Solr Field Facet query to the search query pipeline.

A field facet query computes the top values for a field and returns the list of those values along with a count of the subset of documents in the search results which match that term. Field faceting works best over fields which contain a single label or set of labels from a finite, controlled lexicon such as product category. Facet field parameters can be tuned for performance, see: Facet Field Configuration.

It’s possible to specify more than one field facets. For each field facet you must specify the field name plus the following additional parameters:

Limit – the maximum number of terms to be returned. Default 100.
Offset – the number of top facet values to skip in the response. Default 0.
Sort - the order in which to list facet values: count ordering is by documents per term, descending, and index ordering is sorted on term values themselves.
Missing - the number of documents in the results set which have no value for the facet field.
Choice of facet method (advanced) - specify Solr algorithm used to calculate facet counts. (See Facet Method Configuration for details). One of:
- enum - small number of distinct categories
- fc ("field cache") - many different values in the field, each document has low number of values, multi-valued field
- fcs ("single value string fields") - good for rapidly changing indexes

For further details see: Solr Faceting Overview.

Configuration

When using Fusion's REST API, the type for this stage is: facet.

Property Description, Type

fieldFacets

Facet Fields

type: array of object

object attributes: {
  enumCacheMinDf : {
    display name: Enum Cache Minimum DF
    type: integer
    exclusiveMinimum : false
    minimum : 0
    }
  field (required) : {
    display name: Field
    type: string
    description : The field whose values you want to facet on.
    }
  limit : {
    display name: Limit
    type: integer
    description : Maximum number of facets to return.
    }
  method : {
    display name: Method
    type: string
    enum: { enum fc fcs     }

    }
  minCount : {
    display name: Minimum Count
    type: integer
    default value: '1'
    description : Lower threshold of term counts to be included.
    }
  missing : {
    display name: Count Missing
    type: boolean
    default value: 'false'
    description : Optionally include a 'missing' facet bucket for documents without the selected field.
    }
  offset : {
    display name: Offset
    type: integer
    description : Offset into list of resulting facets.
    }
  prefix : {
    display name: Prefix
    type: string
    description : Prefix of terms to facet on.
    }
  sort : {
    display name: Sort
    type: string
    description : Ordering of the faceting results.
    enum: { count index     }     }
  threads : {
    display name: Number of Threads
    type: integer
    exclusiveMinimum : false
    minimum : 0
    }
  }