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1.5 Marks
Learning     Outcome(s):
Create entity-relationship     model, relational model, and write SQL queries
Question One
Consider the below schema for a library database and write relational algebra expressions for the following queries  
1. Author ( authorname, citizenship, birthyear) 
2. Book (isbn, title, authorname)
3. Topic (isbn, subject)
4. Branch (libname, city)
5. Instock (isbn, libname, quantity)
1. Give all authors’ names born after 1940. [0.25 Point]
2. Give the names of libraries in Sydney. [0.25 Point]
3. Give the city/cities and “isbn” where each book is held.    [0.25 Point]
4. Give the title of each book on the topic of either alcohol or drugs. [0.25 Point]
5. Give the title and author of each book of which at least two copies are held in a branch located in Melbourne.  [0.50 Point]
1 Mark
Learning     Outcome(s):
Explain database concepts,     systems, and architectures
Question Two
What is the different between the database schema and the database instance? Give an example for each.
1 Mark
Learning     Outcome(s):
Design a database starting from     the conceptual design to the implementation of database schemas
Question Three
Name at least three tables that might be used to store information in the following systems:
a. An e-commerce system such as Amazon.  [0.25 Point]
b. A social media system such as Twitter.    [0.25 Point]
c. A health care system. [0.25 Point]
d. A university system. [0.25 Point]
1.5 Marks
Learning     Outcome(s):
Create entity-relationship     model, relational model, and write SQL queries
Question Four
Given the relation below named Contact_Info, answer the following questions:
SSN
Name
Phone
Email
Age
234-356
Sara Fahad
340-675-9876
[email protected]
22
673-980
Mohammad Ahmed
234-896-2567
[email protected]
28
129-678
Waad Saud
280-986-8736
[email protected]
31
a. What is the relational schema of the relation Contact_Info?  [0.25 Point]
b. What is the degree of the giving relation? [0.25 Point]
c. Is the column Name an atomic attribute/value? If no, justify your answer? [0.25 Point]
d. What are the outputs of the given operations?  
1.                      (Contact_Info)  [0.50 Point]
2.   (Contact_Info)   [0.25 Point]

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