EXAM1 Solution - Database Management Systems (CIS 4301)...

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1 Database Management Systems (CIS 4301) (Spring 2008) Instructor: Dr. Markus Schneider TA: Ganesh Viswanathan Wenjie Yuan Exam 1 (solution) Name: UFID: Email Address: Pledge (Must be signed according to UF Honor Code) On my honor, I have neither given nor received unauthorized aid in doing this assignment. _______________________________________________Signature For scoring use only: Maximum Received Exercise 1 30 Exercise 2 30 Exercise 3 25 Exercise 4 15 Total 100
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2 Exercise 1 (Knowledge Questions) [30 points] (a) By using mathematical notaion and a brief description of what the notation means, explain the following notions precisely (Do not use examples!) 1. Alternative definition of relation. (5 points) Relation instance R r is a finite set of mappings } , , , { 2 1 m R t t t r K = , where D R t i : with ) ( ) ( ) ( 2 1 n A dom A dom A dom D = K 2. Relation schema. (5 points) ) : , : , : ( 2 2 1 1 n n D a D a D a R K = where 0 n , R is a relation name. a i are distinct attributes and D i are domain names. 3. Key. (5 points) Let us assume R(A 1, A 2 ,…,A n ), and let } , , , { 2 1 n A A A X K . X is called key, if the following conditions are fulfilled: - uniqueness: for all relation instances R r of R hols: 2 1 2 1 2 1 ] [ ] [ : , t t X t X t r t t R = = - minimaltiy: there is no X Y , so that uniqueness is fulfilled 4. Union operation on relations. (5 points) (b) What is a database? (5 points) Integrated and structured repository of large collections of persistent data, which
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EXAM1 Solution - Database Management Systems (CIS 4301)...

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