Question
a.
backup
b.
assertion
c.
recovery
d.
trigger
Posted under GATE cse question paper DBMS
Engage with the Community - Add Your Comment
Confused About the Answer? Ask for Details Here.
Know the Explanation? Add it Here.
Q. The statement that is executed automatically by the system as a side effect of the modification of the database is
Similar Questions
Discover Related MCQs
Q. Table A
Id Name Age
----------------
12 Arun 60
15 Shreya 24
99 Rohit 11
Table B
Id Name Age
----------------
15 Shreya 24
25 Hari 40
98 Rohit 20
99 Rohit 11
Table C
Id Phone Area
-----------------
10 2200 02
99 2100 01
Consider the above tables A, B and C. How many tuples does the result of the following SQL query contains?
SELECT A.id
FROM A
WHERE A.age > ALL (SELECT B.age FROM B
WHERE B. name = "arun")
View solution
Q. Consider the following relational schema:
Suppliers(sid:integer, sname:string, city:string, street:string)
Parts(pid:integer, pname:string, color:string)
Catalog(sid:integer, pid:integer, cost:real)
(sid,pid are primary keys)
Assume that, in the suppliers relation above, each supplier and each street within a city has a unique name, and (sname, city) forms a candidate key. No other functional dependencies are implied other than those implied by primary and candidate keys. Which one of the following is TRUE about the above schema?
View solution
Q. Consider the following functional dependencies in a database:
Data_of_Birth → Age
Age → Eligibility
Name → Roll_number
Roll_number → Name
Course_number → Course_name
Course_number → Instructor
(Roll_number, Course_number) → Grade
The relation (Roll_number, Name, Date_of_birth, Age) is:
View solution
Q. Consider the relations r1(P, Q, R) and r2(R, S, T) with primary keys P and R respectively. The relation r1 contains 2000 tuples and r2 contains 2500 tuples. The maximum size of the join r1⋈ r2 is :
View solution
Q. Consider the set of relations shown below and the SQL query that follows.
Students: (Roll_number, Name, Date_of_birth)
Courses: (Course number, Course_name, Instructor)
Grades: (Roll_number, Course_number, Grade)
select distinct Name
from Students, Courses, Grades
where Students. Roll_number = Grades.Roll_number
and Courses.Instructor = Korth
and Courses.Course_number = Grades.Course_number
and Grades.grade = A
Which of the following sets is computed by the above query?
View solution
Q. In a schema with attributes A, B, C, D and E following set of functional dependencies are given
A → B A → C CD → E B → D E → A
Which of the following functional dependencies is NOT implied by the above set?
View solution
Q. What is the min and max number of tables required to convert an ER diagram with 2 entities and 1 relationship between them with partial participation constraints of both entities?
View solution
Q. Relation R is decomposed using a set of functional dependencies, F and relation S is decomposed using another set of functional dependencies G. One decomposition is definitely BCNF, the other is definitely 3NF, but it is not known which is which. To make a guaranteed identification, which one of the following tests should be used on the decompositions? (Assume that the closures of F and G are available).
View solution
Q. Given the basic ER and relational models, which of the following is INCORRECT?
View solution
Q. Consider the following ordering of transactions:
T1 : R(X); T2 : R(X); T1 : w(x); T1 : r(y); T2 : w(x); T2 : Commit; T1: w(y) ; T1: Commit
Which of the following is true?
View solution
Q. Let r be a relation instance with schema R = (A, B, C, D). We define r1 = ΠA, B, C (r) and r2 = ΠA.D (r). Let s = r1 * r2 where * denotes natural join. Given that the decomposition of r into r1 and r2 is lossy, which one of the following is TRUE?
View solution
Q. Which level of locking provides the highest degree of concurrency in a relational data base?
View solution
Q. Consider the relation "enrolled(student, course)" in which (student, course) is the primary key, and the relation "paid(student, amount)" where student is the primary key. Assume no null values and no foreign keys or integrity constraints. Given the following four queries:
Query1: select student from enrolled where
student in (select student from paid)
Query2: select student from paid where
student in (select student from enrolled)
Query3: select E.student from enrolled E, paid P
where E.student = P.student
Query4: select student from paid where exists
(select * from enrolled where enrolled.student
= paid.student)
Which one of the following statements is correct?
View solution
Q. Consider a join (relation algebra) between relations r(R)and s(S) using the nested loop method. There are 3 buffers each of size equal to disk block size, out of which one buffer is reserved for intermediate results. Assuming size(r(R)) < size(s(S)), the join will have fewer number of disk block accesses if
View solution
Q. Consider the following three table to store student enrollements in different courses.
Student(EnrollNo, Name)
Course(CourseID, Name)
EnrollMents(EnrollNo, CourseID)
(EnrollNo,CourseID are primary keys)
What does the following query do?
SELECT S.Name
FROM Student S, Course C, Enrollments E
WHERE S.EnrollNo = E.EnrollNo AND
C.Name = "DBMS" AND
E.CourseID = C.CourseID AND
S.EnrollNo IN
(SELECT S2.EnrollNo
FROM Student S2, Course C2, Enrollments E2
WHERE S2.EnrollNo = E2.EnrollNo AND
E2.CourseID = C2.CourseID
C2.Name = "OS")
View solution
Q. How many serial schedules are possible using n-transactions?
View solution
Q. Given the following relation instance.
x y z
1 4 2
1 5 3
1 6 3
3 2 2
Which of the following functional dependencies are satisfied by the instance? (GATE CS 2000)
View solution
Q. The employee information in a company is stored in the relation
Employee (name, sex, salary, deptName)
(name is primary key )
Consider the following SQL query
select deptName
from Employee
where sex = 'M'
group by deptName
having avg (salary) > (select avg (salary) from Employee)
It returns the names of the department in which
View solution
Q. Consider the following relational schema:
Suppliers(sid:integer, sname:string, city:string, street:string)
Parts(pid:integer, pname:string, color:string)
Catalog(sid:integer, pid:integer, cost:real)
Consider the following relational query on the above database:
SELECT S.sname
FROM Suppliers S
WHERE S.sid NOT IN (SELECT C.sid
FROM Catalog C
WHERE C.pid NOT IN (SELECT P.pid
FROM Parts P
WHERE P.color<> 'blue'))
Assume that relations corresponding to the above schema are not empty. Which one of the following is the correct interpretation of the above query?
View solution
Q. A relational database contains two tables student and department in which student table has columns roll_no, name and dept_id and department table has columns dept_id and dept_name. The following insert statements were executed successfully to populate the empty tables:
Insert into department values (1, 'Mathematics')
Insert into department values (2, 'Physics')
Insert into student values (l, 'Navin', 1)
Insert into student values (2, 'Mukesh', 2)
Insert into student values (3, 'Gita', 1)
How many rows and columns will be retrieved by the following SQL statement?
Select * from student, department
View solution
Suggested Topics
Are you eager to expand your knowledge beyond DBMS? We've curated a selection of related categories that you might find intriguing.
Click on the categories below to discover a wealth of MCQs and enrich your understanding of Computer Science. Happy exploring!