GATE 2022: Database Management system Quiz-9

One of the following four expressions of Relational Algebra is not equivalent to the other three. They are based on the relation R(A, B. and S(B, C)

Let R(A, B, C, D, E) be a relation which has 500000 records. Size of each record is 200 B. Size of attribute A is 16 B . Size of pointer is 4 B and size of the block is 2400 B (assume elements are stored in sorted order of key).
On the execution of the query,
Select ∗ from R where A = ‘GATE’
The difference of the cost in term of number of block transfer from the disk when multilevel index used and when binary search applied without indexing is ______

In B+ tree root node consists (10, 20, 30, 40) as values, with leaf page L1 (2, 6), L2 (10, 13, 16, 17), L3 (20, 21, 23, 28), L4 (30, 32, 36, 38) and L5 (40, 54, 69 87). Suppose that a page can contain at most four data values, and then what would be the impact when the value 25 is inserted?

Which of the given schedules is/are recoverable ?(Multi Select Question)

Consider the following schedule:

S: r₁(A) r₃(D) w₁(B) r₂(B) r₄(B) w₂(C) r₅(C) w₄(E) r₅(E)w₅(B)

How many serial schedules view equal to schedule (S)?

The following table has two attributes A and C where A is the primary key and C is the foreign key referencing A with on-delete cascade.

The number of tupples that must be additionally deleted to preserve referential integrity when the tupple (4, 3) is deleted is _______.

Consider following 2 queries with relation schema :

Student (ID., name, DEPT)

Courses (CID.ID, Grade, DEPT)

Q1: Select *

      From Student S

      Where not exists (select *

                                 from Course C

                                 Where C.ID = S.ID and C.Id> 4.0)

Q2:(_ID (Student) – π_ID(σ_{Grade> 4.0} (Course))) ⋈Student.

Which of the following query results “all students who never got a grade above 4.0” ?

Suppose the process P has been running for several days when a new process Q starts up and begins contending with P for resources. Which of the following is true?

Consider the following B⁺ tree with the order of internal and leaf nodes as 3 and 2 respectively:

Key to represent relationship between tables is called?

Consider the relation given below and find the maximum normal form applicable to them

i. R (A, B) with productions { A →  B }

ii. R (A, B) with productions { B →  A }

iii. R (A, B) with productions {A →  B, B →  A }

iv. R (A, B, C) with productions {A →  B, B →  A, AB →  C }

Consider the following tables given below where p, q, r are column names:

(1) Lossy

(2) Lossless

Give the numbers in the same order as the property is defined by the above tables. For example write 12 if Table I is Lossy and Table II is Lossless and so on.

CREATE TABLE Student(stu_id NUMERIC NOT NULL, Name VARCHAR(20) , dept_name VARCHAR(20) UNIQUE(Name));

INSERT INTO Student VALUES(1001, Arun, CSE);

INSERT INTO Student VALUES(1002,Rita,ECE );

INSERT INTO Student VALUES(1005,Rita,EE );

What will be the result of the query?

The minimum number of states a transaction can move before leaving the system are ______