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  1. Core Server
  2. SERVER-3310

Query optimizer should efficiently handle $in and sort with compound index.

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Details

    • Improvement
    • Status: Closed
    • Major - P3
    • Resolution: Fixed
    • None
    • 2.5.5
    • Querying

    Description

      Suppose you have an index on

      {friend_id: 1, date: -1}

      Then, suppose you have a query like this:

      db.things.find({ friend_id: {$in: [lots_of_ids]}}).sort(

      {date: -1}

      ).limit(20)

      Currently, this does a scanAndOrder and scans quite a few documents. Can we optimize?

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        Issue Links

          depends on

          Improvement - An improvement or enhancement to an existing feature or task. SERVER-5063 $in on first compound key element and limit efficiency

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

          Bug - A problem which impairs or prevents the functions of the product. SERVER-959 never do a table scan to answer db.f.find( {y:10} ).sort( {x:1} ) when have index {x:1,y:1}

          • Major - P3 - Major loss of function.
          • Closed
          is depended on by

          Improvement - An improvement or enhancement to an existing feature or task. SERVER-10472 find(a).sort(b,_id) doesn't use index(a,b) to minimize scans

          • Major - P3 - Major loss of function.
          • Backlog
          is duplicated by

          Improvement - An improvement or enhancement to an existing feature or task. SERVER-2148 $in with sort doesnt use index

          • Minor - P4 - Minor loss of function, or other problem where easy workaround is present.
          • Closed

          Improvement - An improvement or enhancement to an existing feature or task. SERVER-5032 unnecessarily large nScanned occurs during sharded $in queries with sort() and limit()

          • Minor - P4 - Minor loss of function, or other problem where easy workaround is present.
          • Closed
          is related to

          Bug - A problem which impairs or prevents the functions of the product. SERVER-11116 cursor limit has inconsistent effect on compound index scan count

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

          Bug - A problem which impairs or prevents the functions of the product. SERVER-7742 Improve the way indexes are used to do a range query on one field and sort on another

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

          Improvement - An improvement or enhancement to an existing feature or task. SERVER-3758 push limit down into index scan for sort + limit queries

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

          Improvement - An improvement or enhancement to an existing feature or task. SERVER-8790 Introduce composable "stages" in query execution

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

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              Dates

                Created:
                Updated:
                Resolved: