Details

    • Type: New Feature
    • Status: Resolved
    • Priority: Minor
    • Resolution: Fixed
    • Affects Version/s: 6.0
    • Fix Version/s: 4.6, 6.0
    • Component/s: search
    • Labels:
      None

      Description

      This ticket introduces the CollapsingQParserPlugin

      The CollapsingQParserPlugin is a PostFilter that performs field collapsing. This is a high performance alternative to standard Solr field collapsing (with ngroups) when the number of distinct groups in the result set is high.

      For example in one performance test, a search with 10 million full results and 1 million collapsed groups:
      Standard grouping with ngroups : 17 seconds.
      CollapsingQParserPlugin: 300 milli-seconds.

      Sample syntax:

      Collapse based on the highest scoring document:

      fq=(!collapse field=<field_name>}
      

      Collapse based on the min value of a numeric field:

      fq={!collapse field=<field_name> min=<field_name>}
      

      Collapse based on the max value of a numeric field:

      fq={!collapse field=<field_name> max=<field_name>}
      

      Collapse with a null policy:

      fq={!collapse field=<field_name> nullPolicy=<null_policy>}
      

      There are three null policies:
      ignore : removes docs with a null value in the collapse field (default).
      expand : treats each doc with a null value in the collapse field as a separate group.
      collapse : collapses all docs with a null value into a single group using either highest score, or min/max.

      The CollapsingQParserPlugin also fully supports the QueryElevationComponent

      Note: The July 16 patch also includes and ExpandComponent that expands the collapsed groups for the current search result page. This functionality will be moved to it's own ticket.

        Attachments

        1. SOLR-5027.patch
          10 kB
          Joel Bernstein
        2. SOLR-5027.patch
          13 kB
          Joel Bernstein
        3. SOLR-5027.patch
          26 kB
          Joel Bernstein
        4. SOLR-5027.patch
          27 kB
          Joel Bernstein
        5. SOLR-5027.patch
          31 kB
          Joel Bernstein
        6. SOLR-5027.patch
          37 kB
          Joel Bernstein
        7. SOLR-5027.patch
          60 kB
          Joel Bernstein
        8. SOLR-5027.patch
          60 kB
          Joel Bernstein
        9. SOLR-5027.patch
          61 kB
          Joel Bernstein

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              • Assignee:
                joel.bernstein Joel Bernstein
                Reporter:
                joel.bernstein Joel Bernstein
              • Votes:
                3 Vote for this issue
                Watchers:
                21 Start watching this issue

                Dates

                • Created:
                  Updated:
                  Resolved: