when $count is at the end of multiple stages that don't change the number of documents in pipeline, those stages can be eliminated

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    • Type: Improvement
    • Resolution: Unresolved
    • Priority: Major - P3
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    • Affects Version/s: None
    • Component/s: Aggregation Framework
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    • Query Optimization
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    • 3
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      Something that looks like this:

      {$match:{}},
      {$project:{}},
      {$lookup:{}},
      {$addFields:{}},
      {$lookup:{}},
      {$count:"c"}
      

      is basically a $match followed by a $count. It would be nice if aggregation had a way of figuring that out.

            Assignee:
            [DO NOT USE] Backlog - Query Optimization
            Reporter:
            Asya Kamsky
            Votes:
            1 Vote for this issue
            Watchers:
            12 Start watching this issue

              Created:
              Updated: