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T. Andrew Yang
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Last updated: 7/13/2022: Lab 2 posted 6/5/2022: first posted |
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CSCI
5533 Distributed Information Systems
NOTE: When preparing your
answers, you are welcome to use any resources, including the text books.
However, make sure you properly cite the work of other researchers or
professionals. Visit http://cse.uhcl.edu/yang/citing.htm for more information about cited references. Warning: Missing or improper cited references in your
answers will result in poor scores.
Total
points: 100
Q1. (10 pts) What is a distributed system?
Q2. (15 pts) Based on your answer above, is
the Internet an example of a distributed system? Justify your answer.
Q3. (10 pts) What is a distributed information system?
Q4. (15 pts) Based on your answer above, is
the Internet an example of a distributed information system? Justify your
answer.
Q5. (10 pts) What is the relationship
between a distributed system and a distributed information system?
Q6. (10 pts) Explain the difference of query processing in a centralized database system versus query processing in a distributed database system.
Q7. The following questions are based on the
relations Book and Author as shown below.
|
Relation: Book |
|||
|
Book_ID |
Book_Name |
Book_Price |
Author_ID |
|
111 |
An Interesting Book |
35.95 |
1001 |
|
222 |
A Travel Guide |
11.50 |
1002 |
|
333 |
How to Build a Shed |
55.90 |
1003 |
|
444 |
A Nature Lover’s Guide |
39.99 |
1003 |
|
555 |
How to Become an Effective Learner |
99.99 |
1002 |
|
666 |
Here Comes the Magician |
123.00 |
1003 |
|
Relation:
Author |
|
|
Author_ID |
Author_Name |
|
1001 |
John Doe |
|
1002 |
A.J. Smith |
|
1003 |
Peter Wong |
|
1004 |
Jane Chaudhary |
7a. (15
pts) Explain what natural join means. Show the result of Author ⋈
Book. (natural join)
7b. (15 pts) Explain what outer join means. Show the result
of Author ⟕ Book. (left outer join)
Hint: Read Chapter 2 of the Özsu
and Valduriez book, Principles of
Distributed Database Systems, 3rd edition.
Go
to the Index
Total
points: 100
Q1.
(10 pts) Explain why the Remote
Procedure Calls (RPCs) are considered as a type of transient and synchronous
communication between processes.
Q2.
(10 pts) Explain why the
Message-Queuing model is considered as a type of persistent and asynchronous
communication between processes.
Q3.
(10 pts) Compare the trade-offs
between RPCs and Message-Queuing systems. Explain when (that is, for
what applications) you would choose one over the other.
Q4.
(10 pts) Explain what a middleware
is, and what distribution transparency
is. Then explain how the middleware helps to provide distribution transparency in a
distributed system.
Q5.
(10 pts) The following
questions are based on the relations Book and Author as shown below.
|
Relation: Book |
|||
|
Book_ID |
Book_Name |
Book_Price |
Author_ID |
|
111 |
An Interesting Book |
35.95 |
1001 |
|
222 |
A Travel Guide |
11.50 |
1002 |
|
333 |
How to Build a Shed |
55.90 |
1003 |
|
444 |
A Nature Lover’s Guide |
39.99 |
1003 |
|
555 |
How to Become an Effective Learner |
99.99 |
1002 |
|
666 |
Here Comes the Magician |
123.00 |
1003 |
|
Relation:
Author |
|
|
Author_ID |
Author_Name |
|
1001 |
John Doe |
|
1002 |
A.J. Smith |
|
1003 |
Peter Wong |
|
1004 |
Jane Chaudhary |
Q6.
Problem 3.1 from the textbook.
Given relation EMP as in Figure 3.3, let p1: TITLE < “Programmer” and p2: TITLE > “Programmer” be two simple
predicates. Assume that character strings have an order among them, based on
the alphabetical order.
1.1.1.
(10 pts) Perform a horizontal
fragmentation of relation EMP with respect to {p1, p2}.
1.1.2.
(10 pts) Explain why the resulting
fragmentation (EMP1, EMP2) does not fulfill the correctness rules of
fragmentation.
1.1.3.
(15 pts) Modify the
predicates p1 and p2 so that they partition EMP obeying the correctness rules
of fragmentaion. To do this, modify the predicates,
compose all minterm predicates and deduce the
corresponding implications, and then perform a horizontal fragmentation of EMP
based on these minterm predicates.
1.1.4.
(15 pts) Finally, show that
the result has completeness, reconstruction and disjointness properties.
Go
to the Index