mongodb - Do we need to set the index on the collection for the order by fields also? -


i have read removing unncecessary index can improve mongodb's performance lot . working on application dependent on mongodb heavily . have seen of queries inside application querying data using order on 2 attributes of document .

my question

do need set index on collection order fields also?

thanks in advance.

i think so. refer: http://docs.mongodb.org/manual/tutorial/sort-results-with-indexes/ says:

in mongodb sort operations sort documents based on indexed field provide greatest performance. indexes in mongodb, in other databases, have order: result, using index access documents returns in same order index.


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