Database Management System MCQs
11. Question
The order of an internal node in a B+ tree index is the maximum number of children it can have. Suppose that a child pointer takes 6 bytes, the search field value takes 14 bytes, and the block size is 512 bytes. What is the order of the internal node?
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12. Question
Consider the following relation schema pertaining to a students database:
Students (rollno, name, address)
Enroll(rollno,courseno, coursename)
Where the primary keys are shown underlined. The number of tuples in the student and Enroll tables are 120 and 8 respectively. What are the maximum and
minimum number of tuples that can be present in (Student * Enroll), where ‘*’ denotes natural join?
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13. Question
Relation R has eight attributes ABCDEFGH. Fields of R contain only atomic values.
F = {CH → G, A →BC, B →CFH, E →A, F →EG} is a set of functional dependencies (FDs) so that F+ is exactly the set of FDs that hold for R
How many candidate keys does the relation R have?
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14. Question
The relation scheme Student Performance (name, courseNo, rollNo, grade) has
the following functional dependencies:
name, courseNo, → grade
rollNo, courseNo → grade
name → rollNo
rollNo → name
The highest normal form of this relation scheme is
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15. Question
Suppose R1(A,B) and R2(C,D) are two relation schema. Let r1 and r2 be the corresponding relation instances. B is foreign key that refers to C in R2. If data in r1 and r2 satisfy referential integrity constraints, which of the following is ALWAYS TRUE?(GATE-2012)
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