Uploaded image for project: 'Core Server'
  1. Core Server
  2. SERVER-4437

aggregation: support windowing operation on pipelines

    XMLWordPrintableJSON

Details

    • New Feature
    • Status: Closed
    • Major - P3
    • Resolution: Done
    • None
    • None
    • Aggregation Framework
    • None
    • Query Optimization

    Description

      postgres supports a windowing capability that allows for calculations within a window of visible data; this is for streaming data.

      It's easy to imagine supporting something like a $window pipeline operator, which specifies how many documents to include in the window. Within, aggregate expressions can reference documents within the window using some kind of indexing. This can be used to calculate things like moving averages, e.g., have a window of 5 items, and create a computed field that is (doc[0] + doc[-1] + doc[-2] + doc[-3] + doc[-4])/5, or something like that.

      Attachments

        Issue Links

          depends on

          Task - A task that needs to be done. SERVER-52328 Enable feature flag for Window Functions

          • Blocker - P1 - Blocks development and/or testing work, production could not run.
          • Closed
          is related to

          New Feature - A new feature of the product, which has yet to be developed. SERVER-447 new aggregation framework

          • Major - P3 - Major loss of function.
          • Closed
          related to

          New Feature - A new feature of the product, which has yet to be developed. SERVER-29161 Ability to access previous document in $group aggregation

          • Major - P3 - Major loss of function.
          • Closed

          Improvement - An improvement or enhancement to an existing feature or task. SERVER-29339 allow using $reduce expression as accumulator in $group

          • Major - P3 - Major loss of function.
          • Backlog

          Activity

            People

              backlog-query-optimization Backlog - Query Optimization
              dan@mongodb.com Daniel Pasette (Inactive)
              Votes:
              10 Vote for this issue
              Watchers:
              11 Start watching this issue

              Dates

                Created:
                Updated:
                Resolved: