InterviewSolution
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InterviewSolution
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Adding an index can potentially decrease the speed of which of the following operations? |
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Answer» YES, there is very MUCH a simpler way of achieving this without having to do this programmatically. The $unwind operator deconstructs an array field resulting in a document for each ELEMENT. Consider user “John” with multiple addresses { "_id" : 1, "name" : "John", addresses: [ "Permanent Addr", "TEMPORARY Addr", "Office Addr"] } db.users.aggregate( [ { $unwind : "$addresses" } ] )would result in 3 documents, one for each of the addresses { "_id" : 1, " name " : " John ", " addresses " : "Permanent Addr" } { "_id" : 1, " name " : " John ", " addresses " : "Temporary Addr" } { "_id" : 1, " name " : " John ", " addresses " : "Office Addr" } |
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