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pythonmongodbpymongodata-miningtext-mining

How to list the outer-most fields of a large document usign PyMongo?

I am just having difficulties to understand this, how can I list outer-most fields when I am working with a huge text datasets? I am trying to implement it in Mongodb and pymongo? any suggestions?

Solution

  • I am not sure what you need, but maybe the bellow can help.

    Query

    • this query returns an array with all the names of the outer fields
    • objectToArray to convert ROOT document to array
    • get the first member that is the field name

    PlayMongo

    aggregate(
[{"$project": 
    {"_id": 0,
      "outer-fields": 
      {"$map": 
        {"input": 
          {"$map": 
            {"input": {"$objectToArray": "$$ROOT"},
              "in": ["$$m.k", "$$m.v"],
              "as": "m"}},
          "in": {"$arrayElemAt": ["$$this", 0]}}}}}])