MongoDB Exam C100DBA Topic 1 Question 91 Discussion

Actual exam question for MongoDB's C100DBA exam

Question #: 91
Topic #: 1

[All C100DBA Questions]

Consider the following document:

> db.c.find()

{ "_id" : 12, b : [ 3, 5, 7, 2, 1, -4, 3, 12 ] }

Which of the following queries on the "c" collection will return only the first five elements of the array in the "b"

field? E.g.,

Document you want returned by your query:

{ "_id" : 12, "b" : [ 3, 5, 7, 2, 1 ] >

Adb.c.find( { > , { b : { $slice : [ 0 , 5 ] } } )

Bdb.c.find( { b : [ 0 , 5 ] > )

Cdb.c.find( { > , { b : { $substr[ 0 , 5 ] > > )

Ddb.c.find( { > , { b : [ 0, 1, 2, 3, 4, 5 ] > )

Edb.c.find( { > , { b : [ 0 , 5 ] > )

Show Suggested Answer

Suggested Answer: A

by Marta at Jul 03, 2024, 05:24 PM

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Sharen

4 months ago

Personally, I find all this MongoDB syntax a bit of a headache. I prefer good old SQL, where things make sense. *chuckles*

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Latanya

3 months ago

Yeah, that looks like the correct query to return the first five elements of the array.

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Ayesha

3 months ago

I think the answer is A) db.c.find( { > , { b : { $slice : [ 0 , 5 ] } } )

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Goldie

4 months ago

I agree, SQL is much more straightforward.

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Benton

5 months ago

I believe option A is correct because $slice is used to return a subset of an array.

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Raul

5 months ago

I'm not sure, but I think option C might also work.

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Lai

5 months ago

I'm going with Option A. Can't beat the classic $slice approach for array slicing.

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Andree

4 months ago

Agreed, $slice is a classic choice for array slicing.

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Caprice

4 months ago

I think Option A is the way to go.

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Theodora

5 months ago

Haha, Option B is just silly. Who would use an array of indexes like that? Option A is clearly the correct choice.

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Nakita

5 months ago

I think Option D is the way to go. Specifying the index positions directly seems more straightforward.

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Kimbery

4 months ago

Got it, thanks for the clarification!

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Catalina

4 months ago

Yes, Option A is correct. It uses the $slice operator to return the first five elements of the array in the 'b' field.

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Erasmo

4 months ago

So, would Option A be the correct choice then?

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Ilene

5 months ago

Option D is incorrect. You need to use the $slice operator to return only the first five elements of the array.

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Belen

5 months ago

I agree with Roxanne, option A seems to be the right choice.

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Roxanne

5 months ago

I think the correct answer is A.

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Josue

5 months ago

Option A looks good to me. The $slice operator should do the trick to get the first 5 elements of the array.

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Whitney

5 months ago

I agree, using the $slice operator in the query seems like the right approach.

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Rosalia

5 months ago

Option A looks good to me. The $slice operator should do the trick to get the first 5 elements of the array.

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