In the schema (dept name, size) we have relations total inst 2007, total inst 2008. Which dependency have lead to this relation ?

Relation dept year(dept name, total inst 2007, total inst 2008, total inst 2009). Here the only functional dependencies are from dept name to the other attributes. This relation is in

A

Fourth NF

B

BCNF

C

Third NF

D

Second NF

Given the following schema: employees(emp-id, first-name, last-name, hire-date, dept-id, salary) departments(dept-id, dept-name, manager-id, location-id) You want to display the last names and hire dates of all latest hires in their respective departments in the location ID 1700. You issue the following query: SQL>SELECT last-name, hire-date FROM employees WHERE (dept-id, hire-date) IN (SELECT dept-id, MAX(hire-date) FROM employees JOIN departments USING(dept-id) WHERE location-id = 1700 GROUP BY dept-id); What is the outcome?

A

It executes but does not give the correct result

B

It executes and gives the correct result.

C

It generates an error because of pairwise comparison

D

It generates an error because the GROUP BY clause cannot be used with table joins in a subquery.

Consider the relation Emp-Dept with SSn as key Ename SSn EAddr Dept. No Dept. Name Dept. Manager SSn Which of the following is (are) invalid operation(s)? a) Inserting an employee without name and address b) Inserting an employee with only SSn c) Inserting a department with no employee d) Inserting an employee without SSn

A

a

B

d

C

c and d

D

b and c

Consider a database that has the relation schemas EMP(EmpId, EmpName, DeptId), and DEPT(DeptName, DeptId) Note that the deptId can be permitted to be NULL in the relation EMP. Consider the following queries on the database expressed in tuple relational calculus. (I) { t |∃u ∈ EMP(tEmpName] = u[EmpName] ∧ ∀ v∈ DEPT(t[DeptId] ≠ v[DeptId]))} (II) {t |∃ u ∈ EMP(t[EmpName] = u[EmpName] ∧ ∃ v ∈ DEPT(t[DeptId] ≠ v[DeptId]))} (III) {t | ∃ u∈ EMP(t[EmpName] = u[EmpName] ∧ ∃ v ∈ DEPT(t[DeptId] = v[DeptId]))} Which of the above queries are safe?

A

(I) and (II) only

B

(I) and (III) only

C

(II) and (III) only

D

(I), (II) and (III)

Department (dept name, building, budget) and Employee (employee_id, name, dept name, salary) Here the dept_name attribute appears in both the relations. Here using common attributes in relation schema is one way of relating ___________ relations.

A

Attributes of common

B

Tuple of common

C

Tuple of distinct

D

Attributes of distinct

Consider the following four relational schemas. For each schema, all non-trivial functional dependencies are listed. The underlined attributes are the respective primary keys. Schema I: Field ‘courses’ is a set-valued attribute containing the set of courses a student has registered for. Non-trivial functional dependency: rollno → courses Schema II: Non-trivial functional dependencies: rollno, courseid → email email → rollno Schema III: Non-trivial functional dependencies: rollno, courseid → marks, grade marks → grade Schema IV: Non-trivial functional dependencies: rollno, courseid → credit courseid → credit Which one of the relational schemas above is in 3NF but not in BCNF?

A

Schema I

B

Schema II

C

Schema III

D

Schema IV

The given bar graph represents the sales of automobiles (in Rs. crores) by five companies A. B, C, D and E in the years 2007-2008 and 2008-2009. Study the bar graph and answer the question that follows. (Note: The data shown below is only for mathematical exercise. It does not represent the actual figures of the companies) What should have been the sales (in Rs. crores) of company E in 2008-2009 so that it would have shown the same increase over 2007-2008 as shown by the sales of automobiles of company C during these years?

A

1,130

B

1,360

C

1,650

D

1,520

The given bar graph represents data of the production of paper (in ten lakh tonnes) by three different companies X, Y and Z during the years 2008 to 2012. The x-axis shows the 'years' and the y-axis represents the 'production of paper (ten lakh tonnes)'. (Note: The data shown is only for mathematical exercise. They do not represent actual figures.) The total production of Company Y during 2008 and 2009 and Company X for 2011 and 2012 taken together is p% (p is correct to the nearest integer) more than the total production of Company Z during 2010, 2011 and 2012. The total production of Company Z during 2008 and 2009 taken together is q% (q is correct to the nearest integer) less than the total production of Company X during 2008, 2009 and 2012 and Company Y during 2010 and 2011 all together. What is the positive difference between p and q ?

A

19

B

29

C

21

D

31

In the year 2007, which is not a leap year, there are 28 days in February and the total days in the year are 365. In 2008, which is a leap year, there are 29 days in February and the total days in the year are 366. If the date May 16, 2007 is a Wednesday: Then which one of the following days would fall on the date May 16, 2008?

A

Wednesday

B

Tuesday

C

Friday

D

Saturday

A

1 and 2

B

2 and 3

C

1 and 4

D

Only 2

In the schema (dept name, size) we have relations total inst 2007, total inst 2008. Which dependency have lead to this relation ?

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