CS2550 Sample Exam Questions

Which of the following is the most correct?
A. The referential integrity rule ensures that people, things and events are uniquely identified in a database.
B. The referential integrity rule prohibits foreign keys to have null values.
C. Each operator of relational algebra transforms one or more tables into a new table.
D. The natural join operator provides the ability to include nonmatching rows in the result table as well as matching rows.

 

  Which of the following SQL statements would correctly list the names of customers that have purchased Black Ink Jet Cartridges based on the OrderEntry Schema below?
A. A
B. B
C. C
D. D


A.
SELECT DISTINCT CustFirstName, CustLastName
FROM Customer c, OrdLine l, OrderTbl o
WHERE c.CustNo = o.CustNo
AND o.OrdNo = l.OrdNo
AND l.ProdNo = p.ProdNo
AND ProdName = 'Black Ink Jet Cartridge';

B.
SELECT DISTINCT CustFirstName, CustLastName
FROM Customer c, OrdLine l, OrderTbl o, Product p
WHERE c.CustNo = o.CustNo
AND o.OrdNo = l.OrdNo
AND l.ProdNo = p.ProdNo
AND ProdName = 'Black Ink Jet Cartridge';

C.
SELECT DISTINCT CustFirstName, CustLastName
FROM Customer c, OrdLine l, OrderTbl o, Product p
WHERE c.CustNo = o.CustNo
AND o.OrdNo = l.OrdNo
AND ProdName = 'Black Ink Jet Cartridge';


D.
SELECT DISTINCT CustFirstName, CustLastName
FROM Customer c, OrdLine l, OrderTbl o, Product p
WHERE c.CustNo = o.CustNo
AND l.ProdNo = p.ProdNo
AND ProdName = "Black Ink Jet Cartridge";

Customer (CustNo, CustFirstName, CustLastName, CustStreet, CustCity, CustState, CustZip, CustBal)
OrderTbl ( OrdNo, OrdDate, CustNo, EmpNo, OrdName, OrdStreet, OrdCity, OrdState, OrdZip)
Employee (EmpNo, EmpFirstName, EmpLastName, EmpPhone, EmpMail, SupEmpNo, EmpCommRate)
Product (ProdNo, ProdName, ProdMfg, ProdQOH, ProdPrice, ProdNextShipDate)
OrdLine (OrdNo, ProdNo, Qty)