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Mongodb Query Optimization


Have slow database queries? Get more information on the performance of your queries using the explain feature. Using the mongo shell, invoke the explain() method on a cursor:

> db.collection.find(query).explain()

example :

> db.user.find().explain();


The result will be a document that contains the explain output:
{
   "cursor" : "BasicCursor",
   "indexBounds" : [ ],
   "nscanned" : 57594,
   "nscannedObjects" : 57594,
   "nYields" : 2 ,
   "n" : 3 ,
   "millis" : 108,
   "indexOnly" : false,
   "isMultiKey" : false,
   "nChunkSkips" : 0
}



Cheers  !!!!!!!!!!!!!!!!!

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