QUESTION: 57

Below is a sample document in a given collection test.

{ a : 5, b : 3, c: 2, d : 1 >

Given a compound index { a: 1, b:l, c:l, d:l}, Which of the below query will not use in- memory sorting? Select all valid.

db.test.find( { a: 5, b: 3 } ).sort( { c: 1, d : 1 } )
db.test.find( { a: 5, b: 3 } ).sort( { a: 1} )
db.test.find( { a: 5, b: 3 } ).sort( { a: 1, b: 1, c: 1 > )
db.test.find( { a: 5, b: 3 } ).sort( {c: 1 } )

Answer(s): A,D

Reveal Solution Next Question

QUESTION: 58

Which of the following is incorrect statement about find and findOne operations in MongoDB?

findQ returns all the documents in a collection while findOne() retrieves only the first one.
find.limit(l) is not the same query as findOne()
findOneQ returns the actual first document retrieved from a collection
findQ and findOneQ returns cursors to the collection documents

Answer(s): D

Reveal Solution Next Question