SQL GATE CS PYQ Quiz

Table A:

Table B:

Table C:

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") 

A table T(X, Y) initially has one record (1, 1). New records are inserted 128 times with:

X = MX + 1, Y = 2*MY + 1

where MX and MY are the current maximums of X and Y.What will MAX(X) and MAX(Y) be after all insertions?

SELECT Y FROM T WHERE X=7;

Database table by name Loan_Records is given below.

What is the output of the following SQL query?

SELECT Count(*) 
FROM  ( ( SELECT Borrower, Bank_Manager 
          FROM Loan_Records) AS S 
          NATURAL JOIN ( SELECT Bank_Manager, Loan_Amount 
                         FROM Loan_Records) AS T );

A relational schema for a train reservation database is given below. Passenger (pid, pname, age) Reservation (pid, class, tid)

Table: Passenger

Table : Reservation

What pids are returned by the following SQL query for the above instance of the tables?

SLECT pid
FROM Reservation ,
WHERE class ‘AC’ AND
    EXISTS (SELECT *
       FROM Passenger
       WHERE age > 65 AND
       Passenger. pid = Reservation.pid)

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?
 

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)

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?

Consider a relation geq which represents “greater than or equal to”, that is, (x,y) ∈ geq only if y >= x.

create table geq
( 
  ib integer not null
  ub integer not null
  primary key 1b
  foreign key (ub) references geq on delete cascade 
)

Which of the following is possible if a tuple (x,y) is deleted?

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

Select operation in SQL is equivalent to

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?