DocuStores Quiz

Document stores can store a potentially big collection of trees as long as they are homogeneous

• True

• False

We can join different collections natively

• True

• False

We can not validate data after ETL-ing.

• True

• False

MongoDB stores JSON internally in an optimized binary format, called ____.

MongoDB offers a _______ _______ for users.

• Low-level, Querying language

• High-level, Querying language

• Low-level, API

• High-level, API

Using B+ trees, we can create indices even on multiple fields

• True

• False

Children of a node in a B+ tree have to be in a fixed range.

• True

• False

We make the following index: {A: 1, B: -1, C: -1}. Which one of the following queries directly benefit from it?
(details left out for simplicity, assume that we have some sort queries for the listed fields)

• A, B

• B

• B, C

• A, B, C

Suppose we have the following documents:

  { "x": 10 },  { "x": [ 5, 15 ] },{ "x": 15 },  { "x": [ 5, 25] },{ "x": [ 20, 25] },

 

Which elements will the following query return?

db.test.find({"x" : {"$gt" : 10, "$lt" : 20}})

• { "x": 10 }

• { "x": [ 5, 15 ] }

• { "x": 15 }

• { "x": [ 5, 25] }

• { "x": [ 20, 25] }

In MongoDB, it is impossible to sort on a field with values in different data types.

• True

• False