NoSQL

Question 1

Which is a limit of relational databases?

Answer 1

Joins can be costly.

Question 2

Which type of NoSQL database is based on sets of nodes and edges between nodes?

Answer 2

Graph database

Question 3

Which is not an advantage of NoSQL databases?

Answer 3

Support for joins

Question 4

T/F. Expressiveness of query language is important to data science tasks.

Answer 4

TRUE

Question 5

T/F. Data quality should be taken into account during data preparation.

Answer 5

TRUE

Question 6

What technique is used to visualize correlations between two variables?

Answer 6

Scatter plots

Question 7

Which is not a type of data set used in data science model building?

Question 8

What markup language can be used for sharing models between tools?

Answer 8

Predictive Modelling Markup Language

Question 10

CSV/TSV

Question 11

JSON

Question 12

Python

Question 13

MongoDB

Question 14

cursor

Answer 14

a pointer to a record - helpful when an entire result set can’t fit into memory

Question 15

outlier

Answer 15

find a dirty data set

Question 17

Documents consist of keys and values.

Answer 17

TRUE

Question 18

In JSON structures, keys are usually what data type?

Answer 18

String

Question 19

csv.DictReader Python function can be used to read tabular data into a Python dictionary.

Answer 19

TRUE

Question 20

Which driver is used in Python to work with MongoDB?

Answer 20

pymongo

Question 21

When converting data to MongoDB format, we can use Python dictionary functions.

Answer 21

TRUE

Question 22

Data type conversions rarely need to be performed during data loads.

Answer 22

FALSE

Question 23

In MongoDB, what can we create to reduce the time needed to find a document based on the value of an attribute?

Answer 23

Index

Question 24

Data frames provide what type of abstract structure?

Answer 24

Table

Question 25

Embedded documents are used to avoid joins.

Answer 25

TRUE

Question 26

What is the top level data structure in Cassandra called?

Answer 26

Keyspace

Question 27

Duplicating data in wide column databases is uncommon.

Answer 27

FALSE

Question 28

Which command is used to specify the nodes in a cluster to connect to?

Answer 28

Cluster

Question 29

One way to catch errors when preparing data is to use which Python statement?

Answer 29

Except

Question 30

Spark and Cassandra can run on the same cluster nodes.

Answer 30

TRUE

Question 31

A Cassandra data model should be based on how you will query the database.

Answer 31

TRUE

Question 32

Graphs consists of rows and tables

Answer 32

FALSE

Question 33

Directed edges are not used in hierarchical relations.

Answer 33

FALSE

Question 34

Using separate files for nodes and edges can simplify data loading.

Answer 34

TRUE

Question 35

What driver is used with Python to work with Neo4j databases?

Answer 35

Py2Neo

Question 36

What data structure can be used to map from nodes and edges to a table data structure?

Answer 36

DataFrame

Question 37

Graphs are especially useful for modeling networks like social networks and road systems.

Answer 37

True