SQL

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") 

Consider a database table T containing two columns X and Y each of type integer. After the creation of the table, one record (X=1, Y=1) is inserted in the table. Let MX and My denote the respective maximum values of X and Y among all records in the table at any point in time. Using MX and MY, new records are inserted in the table 128 times with X and Y values being MX+1, 2*MY+1 respectively. It may be noted that each time after the insertion, values of MX and MY change. What will be the output of the following SQL query after the steps mentioned above are carried out?

SELECT Y FROM T WHERE X=7;

Database table by name Loan_Records is given below.

Borrower    Bank_Manager   Loan_Amount
 Ramesh      Sunderajan     10000.00
 Suresh      Ramgopal       5000.00
 Mahesh      Sunderajan     7000.00

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
pid   pname   age
-----------------
 0    Sachin   65
 1    Rahul    66
 2    Sourav   67
 3    Anil     69

Table : Reservation
pid  class  tid
---------------
 0    AC   8200
 1    AC   8201
 2    SC   8201
 5    AC   8203
 1    SC   8204
 3    AC   8202

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)

Let R and S be relational schemes such that R={a,b,c} and S={c}. Now consider the following queries on the database:

IV) SELECT R.a, R.b
       FROM R,S
            WHERE R.c=S.c

Which of the above queries are equivalent?

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?
 

A library relational database system uses the following schema

USERS (User#, UserName, HomeTown)
BOOKS (Book#, BookTitle, AuthorName)
ISSUED (Book#, User#, Date)

Explain in one English sentence, what each of the following relational algebra queries is designed to determine  

Consider the set of relations given 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 =Sriram
       AND Courses.Course_number = Grades.Course_number
       AND Grades.Grade = A

Which of the following sets is computed by 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)

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?