UV Distributed Information Management - Questionnaire Assignment 3
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The purpose of this questionnaire is to deepen the student's understanding of
assignment 3 and the topics covered in the lecture. The main focus will be the
*correctness* and the *quality* of an answer, not its length. For some
questions, we will provide rough hints to make it easier for you.

You are free to answer the questions directly in this textfile or use another
editor/word processor. The following file formats will be accepted for the
submission: .txt, .pdf, .odt, .doc, .docx. Please note that other file formats
will result in 0 points (for this questionnaire). The preferred file formats are
.txt and .pdf (most word processors support an export as PDF file). In any case,
please make sure that the questions/answers are named/numbered properly!

This questionnaire will be discussed during the after-assignment meeting. Before
the meeting starts, the group will be informed about the preliminary points by
the instructor (either at the beginning of the meeting or via Blackboard). The
final points will be set after the meeting. This questionnaire contributes a
maximum of 8 points (2 points per answer) to the overall points of assignment 3.

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Question F1:
Let's look into relationship in more depth by using the web-based graphical user
interface of Neo4j. Execute the following query and have a look at the resulting
graph:

  MATCH (m:Movie) RETURN m LIMIT 10

Now, click on one of the nodes and three options will pop up. By clicking on
"Expand / Collapse child relationships", you will see all relationship of this
specific Movie node. Then, please answer the following subquestions (each
subanswer is worth 0.5 points):

F1.1 (0.5 points): Name the label of the Movie node you selected.

F1.2 (0.5 points): What types of relationships does the Movie node have?

F1.3 (0.5 points): What are the labels of the nodes that these relationships
connect to?

F1.4 (0.5 points): What are the directions of these relationships?

Answer A1:
<Your answer can go here>

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Question F2:
Explain the semantics (i.e., the meaning) of Q3.

Answer A2:
<Your answer can go here>

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Question F3:
Explain the semantics (i.e., the meaning) of Q4.

Answer A3:
<Your answer can go here>

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Question F4:
Neo4j implements a consistency model called "Causal Consistency". This
consistency model is implemented in Neo4j's clustering architecture where
clustering (in this context) refers to the architecture of Neo4j in a
distributed setting.

Please read through the corresponding entry in Neo4j's documentation (link is in
the hints below) and answer the following subquestions in your own words (each
subanswer is worth 1 points). In addition, there is a bonus question to be
answered if you want to earn a bonus point.

F4.1 (1 point): Briefly describe Neo4j's clustering architecture (0.5 points)
and the difference between primary and secondary nodes in this context
(0.5 points).

F4.2 (1 point): Briefly describe the causal consistency model of Neo4j.

F4.3 (Bonus question worth 1 point): Can you think of pros and cons of the
causal consistency model compared to consistency models that provides strong
consistency guarantees?

Hints:
Consistency model of Neo4j and Causal Consistency in general:
  - https://neo4j.com/docs/operations-manual/current/clustering/introduction/
  - https://en.wikipedia.org/wiki/Causal_consistency

Answer A4:
<Your answer can go here>