Package dev.morphia.aggregation.stages

Class Facet

java.lang.Object
dev.morphia.aggregation.stages.Stage
dev.morphia.aggregation.stages.Facet
public class Facet extends Stage
Processes multiple aggregation pipelines within a single stage on the same set of input documents. Each sub-pipeline has its own field in the output document where its results are stored as an array of documents.

The $facet stage allows you to create multi-faceted aggregations which characterize data across multiple dimensions, or facets, within a single aggregation stage. Multi-faceted aggregations provide multiple filters and categorizations to guide data browsing and analysis. Retailers commonly use faceting to narrow search results by creating filters on product price, manufacturer, size, etc.

Input documents are passed to the $facet stage only once. $facet enables various aggregations on the same set of input documents, without needing to retrieve the input documents multiple times.

  • Method Details

    • facet

      public static Facet facet()
      Creates a new facet stage
      Returns:
      the new stage
      Since:
      2.2
      MongoDB documentation
      Aggregration Pipeline Stage: $facet
      Since server release
      3.4

    • field

      public Facet field(String name, Stage... stages)
      Adds a field to the facet
      Parameters:
      name - the field name
      stages - the pipeline defining the field
      Returns:
      this