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Exam 9: Database Systems

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Question 21

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If a database contained a relation containing information about individual people (name,address,birthday,etc.)and another relation containing information about music composers (name,style,education level,etc.),how would you extend the database's design to include links between each individual and his or her favorite composer?

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The main idea would be to add a new rela...

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Question 22

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Given the two relations X and Y below $\begin{array}{l}\text { X: }&\begin{array}{ll}\mathrm{A} & \mathrm{B} \\\hline 2 & \mathrm{~s} \\5 & \mathrm{Z}\end{array}&\text { Y: }&\begin{array}{ll}\mathrm{C} & \mathrm{D} \\\hline \mathrm{t} & 1 \\\mathrm{r} & 3 \\\mathrm{~W} & 2\end{array}\end{array}$ what values would be in the tuple produced by the following statement? Result ? JOIN X and Y where X.A < Y.D

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Question 23

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Given the relation Employees containing the attributes Name,Address,and CurrentJobID and the relation Jobs containing the attributes JobID,SkillRating,Department,what question is answered by the following SQL statement? SELECT SkillRating FROM Employees,Jobs WHERE Employees.Name = "Joe Smith" AND Employees.CurrentJobID = Jobs.JobID

What information is available from a relational database containing one relation with the attributes Name,Employee identification number,and Address that is not available from a database containing two relations,one with attributes Name and Address and the other with attributes Address and Employee identification number? Explain your answer.

Given the three relations X,Y,and Z below what values would be retrieved by executing the following statement? SELECT X.B,Y.C,Z.F FROM X,Y,Z WHERE X.A > Y.D AND X.A = Z.E

Given the two relations X and Y below what values would be retrieved by executing the following statement? SELECT X.A,X.B,Y.C FROM X,Y WHERE X.A < Y.D

Which of the following accesses a database in terms of a database model?

Which of the following data mining techniques would be applied when trying to identify any underlying heterogeneity within housing patterns in a community?

Given the relation Parts containing the attributes PartName,PartNumber,and SupplierID as well as the relation Suppliers containing the attributes SupplierID,Address,FaxNumber,write a sequence of SELECT,PROJECT,and JOIN operations to obtain the supplier identifications and fax numbers for all the suppliers that supply the part whose part number is X4J26.

Suppose a relation X had the attributes Name,EmployeeID,and Address.Complete the following statement to obtain a list of the names and addresses of all employees. Result ← ___________________________________ from X

Describe the wound-wait protocol.

Given the relation Employees containing the attributes Name,Address,and BirthDate,what question is answered by the following sequence of operations? Temp ? SELECT from Employees where BirthDate < "January 4,1975" Result? PROJECT Name from Temp

Which of the following data mining techniques would be applied when trying to identify common properties between different groups of shoppers?

Which of the following relational operations combine data from more than one relation?

Given the two relations X and Y below draw the relation Result that would be produced by the following statements? Temp ← JOIN X and Y where X.A > Y.D Result ← PROJECT X.B,Y.C from Temp

Which of the following features within a DBMS is not provided to maintain database integrity?

Describe the distinction between class description and cluster analysis.

Which of the following describes only the portion of a database available to a particular user?

Given the relation Employees containing the attributes Name,Address,and CurrentJobID and the relation Jobs containing the attributes JobID,SkillRating,Department,what question is answered by the following sequence of operations? Temp1 ? JOIN Employees and Jobs where Employees.CurrentJobID = Jobs.JobID Temp2 ? SELECT from Temp1 where Department = "Personnel" Result ? PROJECT Name from Temp2

Place an X in the space before those issues that are not problems associated with data mining.Leave the other spaces blank. _____ Cascading rollback _____ Deadlock _____ Incorrect summary problem _____ Lost update problem