Conditionally order $match with $unwind

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    • Fully Compatible
    • Query 10 (02/22/16), Query 11 (03/14/16), Query 12 (04/04/16)
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      The subset of a $match following an $unwind that does not filter on the unwound field can be moved up in the pipeline.

      For example:

      [
  {'$unwind' : "$x"}, 
  {'$match' : {_id : 1, x : {'$gt': 3}  } }
]

      is equivalent to:

      [ 
   {'$match' : {_id : 1} }, 
   {'$unwind' : "$x"}, 
   {'$match' : {x : {'$gt': 3}} }
]

              Assignee:
              Benjamin Murphy (Inactive)
              Reporter:
              Jeffrey Yemin
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                Created:
                Updated:
                Resolved: