Suppose ORACLE relation R(A, B) currently has tuples {(1, 2), (1, 3), (3, 4)} and relation S(B, C) currently has {(2, 5), (4, 6), (7, 8)}. Consider the following two SQL queries SQ1 and SQ2 : SQ1 : Select * From R Full Join S On R.B=S.B; SQ2 : Select * From R Inner Join S On R.B=S.B; The numbers of tuples in the result of the SQL query SQ1 and the SQL query SQ2 are given by : (A) 2 and 6 respectively (B) 6 and 2 respectively (C) 2 and 4 respectively (D) 4 and 2 respectively

Suppose ORACLE relation R(A, B) currently has tuples {(1, 2), (1, 3), (3, 4)} and relation S(B, C) currently has {(2, 5), (4, 6), (7, 8)}. Consider the following two SQL queries SQ1 and SQ2 : 

SQ1 : Select *
From R Full Join S
On R.B=S.B;
SQ2 : Select *
From R Inner Join S
On R.B=S.B;
The numbers of tuples in the result of the SQL query SQ1 and the SQL query
SQ2 are given by :
(A) 2 and 6 respectively (B) 6 and 2 respectively
(C) 2 and 4 respectively (D) 4 and 2 respectively
by

1 Answer

Answer :

(D) 4 and 2 respectively
by

Related questions

Consider the following three SQL queries (Assume the data in the people table) : (a) Select Name from people where Age>21; (b) Select Name from people where Height>180; (c) Select Name from people where (Age>21) or (Height>180); If the SQL queries (a) and (b) above, return 10 rows and 7 rows in the result set respectively, then what is one possible number of rows returned by the SQL query (c) ? (A) 3 (B) 7 (C) 10 (D) 21

Description : Consider the following three SQL queries (Assume the data in the people table) : (a) Select Name from people where Age>21; (b) Select Name from people where Height>180; (c) Select Name from people where (Age>21) or (Height ... number of rows returned by the SQL query (c) ? (A) 3 (B) 7 (C) 10 (D) 21

Last Answer : (C) 10

Consider the following two commands C1 and C2 on the relation R from an SQL database: C1: drop table R; C2: delete from R; Which of the following statements is TRUE? I. Both C1 and C2 delete the schema for R. II. C2 retains relation R, but deletes all tuples in R. III. C1 deletes not only all tuples of R, but also the schema for R. (A) I only (B) I and II only (C) II and III only (D) I, II and III

Description : Consider the following two commands C1 and C2 on the relation R from an SQL database:  C1: drop table R; C2: delete from R; Which of the following statements is TRUE? I. Both C1 and C2 delete the schema for R. II. C2 ... R. (A) I only (B) I and II only (C) II and III only (D) I, II and III

Last Answer : (C) II and III only

Consider a database table R with attributes A and B. Which of the following SQL queries is illegal ? (A) SELECT A FROM R; (B) SELECT A, COUNT(*) FROM R; (C) SELECT A, COUNT(*) FROM R GROUP BY A; (D) SELECT A, B, COUNT(*) FROM R GROUP BY A, B;

Description : Consider a database table R with attributes A and B. Which of the following SQL queries is illegal ? (A) SELECT A FROM R; (B) SELECT A, COUNT(*) FROM R; (C) SELECT A, COUNT(*) FROM R GROUP BY A; (D) SELECT A, B, COUNT(*) FROM R GROUP BY A, B;

Last Answer : (B) SELECT A, COUNT(*) FROM R;

Consider the relations R(A,B) and S(B,C) and the following four relational algebra queries over R and S: I. πA,B(R⋈S) II. R⋈πB(S) III. R∩(πA(R) Χ πB(S)) IV. πA,R.B(R Χ S) where R.B refers to the column B in table R. One can determine that: (A) I, III and IV are the same query. (B) II, III and IV are the same query. (C) I, II and IV are the same query. (D) I, III and III are the same query.

Description : Consider the relations R(A,B) and S(B,C) and the following four relational algebra queries over R and S: I. πA,B(R⋈S) II. R⋈πB(S) III. R∩(πA(R) Χ πB(S)) IV. πA,R.B(R Χ S) where R.B refers to ... IV are the same query. (C) I, II and IV are the same query. (D) I, III and III are the same query.

Last Answer : (D) I, III and III are the same query.

Which of the following is not the function of client? A) Compile queries B) Query optimization C) Receive queries D) Result formatting and presentation

Description : Which of the following is not the function of client? A) Compile queries B) Query optimization C) Receive queries D) Result formatting and presentation

Last Answer : B) Query optimization

Consider the table Student(stuid, name, course, marks). Which one of the following two queries is correct to find the highest marks student in course 5? Q.1. Select S.stuid From student S Where not exists (select * from student e where e course='5' and e marks ≥ s marks) Q.2. Select S.stuid From student S Where s.marks > any (select distinct marks from student S where s.couse = 5) (A) Q.1 (B) Q.2 (C) Both Q.1 and Q.2 (D) Neither Q.1 nor Q.2

Description : Consider the table Student(stuid, name, course, marks). Which one of the following two queries is correct to find the highest marks student in course 5? Q.1. Select S.stuid From student S Where not exists (select * from student ... ) Q.1 (B) Q.2 (C) Both Q.1 and Q.2 (D) Neither Q.1 nor Q.2

Last Answer : (B) Q.2 Explanation: First query gives stuid of students whose marks are greater than all students taking course 5. Second query gives stuid of students whose marks are greater than any student taking ... comparison is between maximum of marks by any student in course 5. So the answer is option D.

………………….. operator is basically a join followed by a project on the attributes of first relation. A) Join B) Semi-Join C) Full Join D) Inner Join

Description : ………………….. operator is basically a join followed by a project on the attributes of first relation. A) Join B) Semi-Join C) Full Join D) Inner Join

Last Answer : B) Semi-Join

Which of the following is/are the Database server functions? i) Data management ii) Transaction management iii) Compile queries iv) Query optimization A) i, ii, and iv only B) i, ii and iii only C) ii, iii and iv only D) All i, ii, iii, and iv

Description : Which of the following is/are the Database server functions? i) Data management ii) Transaction management iii) Compile queries iv) Query optimization A) i, ii, and iv only B) i, ii and iii only C) ii, iii and iv only D) All i, ii, iii, and iv

Last Answer : A) i, ii, and iv only

Consider three CPU intensive processes P1, P2, P3 which require 20, 10 and 30 units of time, arrive at times 1, 3 and 7 respectively. Suppose operating system is implementing Shortest Remaining Time first (preemptive scheduling) algorithm, then .............. context switches are required (suppose context switch at the beginning of Ready queue and at the end of Ready queue are not counted). (A) 3 (B) 2 (C) 4 (D) 5

Description : Consider three CPU intensive processes P1, P2, P3 which require 20, 10 and 30 units of time, arrive at times 1, 3 and 7 respectively. Suppose operating system is implementing Shortest Remaining Time first (preemptive scheduling) ... end of Ready queue are not counted). (A) 3 (B) 2 (C) 4 (D) 5

Last Answer : (A) 3

The number of attributes in relation is called as its ..................... A) Cardinality B) Degree C) Tuples D) Entity

Description : The number of attributes in relation is called as its ..................... A) Cardinality B) Degree C) Tuples D) Entity

Last Answer : B) Degree

An instance of a relation is a time varying set of …………………. A) Tuples B) Rows C) Both of them D) None of them

Description : An instance of a relation is a time varying set of …………………. A) Tuples B) Rows C) Both of them D) None of them

Last Answer : C) Both of them

The number of tuples in a relation is called its …………. While the number of attributes in a relation is called it’s ……………….. A) Degree, Cardinality B) Cardinality, Degree C) Rows, Columns

Description : The number of tuples in a relation is called its …………. While the number of attributes in a relation is called it’s ……………….. A) Degree, Cardinality B) Cardinality, Degree C) Rows, Columns

Last Answer : B) Cardinality, Degree

………………… is a full form of SQL. A) Standard query language B) Sequential query language C) Structured query language D) Server side query language

Description : ………………… is a full form of SQL. A) Standard query language B) Sequential query language C) Structured query language D) Server side query language

Last Answer : A) Standard query language

To select tuples with some salary, Siddharth has written the following erroneous SQL statement : -Technology

Description : To select tuples with some salary, Siddharth has written the following erroneous SQL statement : -Technology

Last Answer : The correct code is :SELECT ID, Salary FROM empsalaryWHERE Salary = 56000 ;

Let R be the rectangular window against which the lines are to be clipped using 2D Sutherland-Cohen line clipping algorithm. The rectangular window has lower left-hand corner at (-5,1) and upper righthand corner at (3,7). Consider the following three lines for clipping with the given end point co-ordinates: Line AB: A(-6,2) and B(-1,8) Line CD: C(-1,5) and D(4,8) Line EF: E(-2,3) and F(1,2) Which of the following line(s) is/are candidate for clipping? (A) AB (B) CD (C) EF (D) AB and CD

Description : Let R be the rectangular window against which the lines are to be clipped using 2D Sutherland-Cohen line clipping algorithm. The rectangular window has lower left-hand corner at (-5,1) and upper righthand corner at (3,7). ... s) is/are candidate for clipping? (A) AB (B) CD (C) EF (D) AB and CD

Last Answer : (D) AB and CD

For execution of DELETE SQL query in JDBC, ............. method must be used. A) executeQuery() B) executeDeleteQuery() C) executeUpdate() D) executeDelete()

Description : For execution of DELETE SQL query in JDBC, ............. method must be used. A) executeQuery() B) executeDeleteQuery() C) executeUpdate() D) executeDelete()

Last Answer : C) executeUpdate()

In distributed databases, location transparency allows for database users, programmers and administrators to treat the data as if it is at one location. A SQL query with location transparency needs to specify: (A) Inheritances (B) Fragments (C) Locations (D) Local formats

Description : In distributed databases, location transparency allows for database users, programmers and administrators to treat the data as if it is at one location. A SQL query with location transparency needs to specify: (A) Inheritances (B) Fragments (C) Locations (D) Local formats 

Last Answer : (B) Fragments

Consider the following database table : Create table test( one integer, two integer, primary key(one), unique(two), check(one≥1 and ≤10), check(two≥1 and ≤5) ); How many data records/tuples atmost can this table contain ? (A) 5 (B) 10 (C) 15 (D) 50

Description : Consider the following database table : Create table test( one integer, two integer, primary key(one), unique(two), check(one≥1 and ≤10), check(two≥1 and ≤5) ); How many data records/tuples atmost can this table contain ?  (A) 5 (B) 10 (C) 15 (D) 50

Last Answer : (A) 5 

Consider a “CUSTOMERS” database table having a column “CITY” filled with all the names of Indian cities (in capital letters). The SQL statement that finds all cities that have “GAR” somewhere in its name, is: (A) Select *from customers where city=’%GAR%’; (B) Select *from customers where city=’$GAR$’; (C) Select *from customers where city like ‘%GAR%’; (D) Select *from customers where city as ’%GAR’;

Description : Consider a CUSTOMERS database table having a column CITY filled with all the names of Indian cities (in capital letters). The SQL statement that finds all cities that have GAR somewhere in its name, ... *from customers where city like %GAR%'; (D) Select *from customers where city as '%GAR';

Last Answer : Answer: C

Suppose the function y and a fuzzy integer number around -4 for x are given as y=(x-3)2+2 Around -4={(2,0.3), (3,0.6), (4,1), (5,0.6), (6,0.3)} respectively. Then f(Around - 4) is given by: (A) {(2,0.6), (3,0.3), (6,1), (11,0.3)} (B) {(2,0.6), (3,1), (6,1), (11,0.3)} (C) {(2,0.6), (3,1), (6,0.6), (11,0.3)} (D) {(2,0.6), (3,0.3), (6,0.6), (11,0.3)}

Description : Suppose the function y and a fuzzy integer number around -4 for x are given as y=(x-3)2+2 Around -4={(2,0.3), (3,0.6), (4,1), (5,0.6), (6,0.3)} respectively. Then f(Around - 4) is given by: (A) {(2,0.6), (3,0.3), ... 6), (3,1), (6,0.6), (11,0.3)} (D) {(2,0.6), (3,0.3), (6,0.6), (11,0.3)}

Last Answer : (C) {(2,0.6), (3,1), (6,0.6), (11,0.3)}

Consider the following table Furniture. Write SQL commands for the statements (i) to (viii) and write output for SQL queries (ix) and (x). -Technology

Description : Consider the following table Furniture. Write SQL commands for the statements (i) to (viii) and write output for SQL queries (ix) and (x). -Technology

Last Answer : SQL commands for the given statements (i) to (viii) ;1. SELECT FCODE, NAME. PRICE FROM Furniture WHERE PRICE < 5000;2. SELECT NAME. PRICE FROM Furniture3.4. WHERE NAME LIKE %table% ;5. SELECT DISTINCT WCODE ... ;15.16. Output for SQL queries (ix) and (x)(ix)SUM(PRICE)6500(x)COUNT(DISTINCT PRICE)5

The relation schemas R1 and R2 form a Lossless join decomposition of R if and only if: (a) R1⋂R2→(R1-R2) (b) R1→R2 (c) R1⋂R2→(R2-R1) (d) R2→R1⋂R2 (A) (a) and (b) happens (B) (a) and (d) happens (C) (a) and (c) happens (D) (b) and (c) happens

Description : The relation schemas R1 and R2 form a Lossless join decomposition of R if and only if: (a) R1⋂R2→(R1-R2) (b) R1→R2 (c) R1⋂R2→(R2-R1) (d) R2→R1⋂R2 (A) (a) and (b) happens (B) (a) and (d) happens (C) (a) and (c) happens (D) (b) and (c) happens

Last Answer : (C) (a) and (c) happens 

Consider a program that consists of 8 pages (from 0 to 7) and we have 4 page frames in the physical memory for the pages. The page reference string is : 1 2 3 2 5 6 3 4 6 3 7 3 1 5 3 6 3 4 2 4 3 4 5 1 The number of page faults in LRU and optimal page replacement algorithms are respectively (without including initial page faults to fill available page frames with pages): (A) 9 and 6 (B) 10 and 7 (C) 9 and 7 (D) 10 and 6

Description : Consider a program that consists of 8 pages (from 0 to 7) and we have 4 page frames in the physical memory for the pages. The page reference string is :  1 2 3 2 5 6 3 4 6 3 7 3 1 5 3 6 3 4 2 4 3 4 5 ... to fill available page frames with pages): (A) 9 and 6 (B) 10 and 7 (C) 9 and 7 (D) 10 and 6

Last Answer : (B) 10 and 7

............... joins are SQL server default A) Outer B) Inner C) Equi D) None of the above

Description : ............... joins are SQL server default A) Outer B) Inner C) Equi D) None of the above

Last Answer : B) Inner

Semi-join strategies are techniques for query processing in distributed database system. Which of the following is a semi-join technique? (A) Only the joining attributes are sent from one site to another and then all of the rows are returned. (B) All of the attributes are sent from one site to another and then only the required rows are returned. (C) Only the joining attributes are sent from one site to another and then only the required rows are returned. (D) All of the attributes are sent from one site to another and then only the required rows are returned.

Description : Semi-join strategies are techniques for query processing in distributed database system. Which of the following is a semi-join technique? (A) Only the joining attributes are sent from one site to ... the attributes are sent from one site to another and then only the required rows are returned.

Last Answer : (C) Only the joining attributes are sent from one site to another and then only the required rows are returned.

In a relational database model, NULL values can be used for all but which one of the following? (A) To allow duplicate tuples in the table by filling the primary key column(s) with NULL. (B) To avoid confusion with actual legitimate data values like 0 (zero) for integer columns and ‘’ (the empty string) for string columns. (C) To leave columns in a tuple marked as “unknown” when the actual value is unknown. (D) To fill a column in a tuple when that column does not really “exist” for that particular tuple.

Description : In a relational database model, NULL values can be used for all but which one of the following? (A) To allow duplicate tuples in the table by filling the primary key column(s) with NULL. (B) To ... D) To fill a column in a tuple when that column does not really exist for that particular tuple.

Last Answer : (A) To allow duplicate tuples in the table by filling the primary key column(s) with NULL.

The number of function points of a proposed system is calculated as 500. Suppose that the system is planned to be developed in Java and the LOC/FP ratio of Java is 50. Estimate the effort (E) required to complete the project using the effort formula of basic COCOMO given below: E = a(KLOC)b Assume that the values of a and b are 2.5 and 1.0 respectively. (A) 25 person months (B) 75 person months (C) 62.5 person months (D) 72.5 person months

Description : The number of function points of a proposed system is calculated as 500. Suppose that the system is planned to be developed in Java and the LOC/FP ratio of Java is 50. Estimate the effort (E) required to ... ) 25 person months (B) 75 person months (C) 62.5 person months (D) 72.5 person months

Last Answer : (C) 62.5 person months 

‘AS’ clause is used in SQL for (A) Selection operation. (B) Rename operation. (C) Join operation. (D) Projection operation.

Description : ‘AS’ clause is used in SQL for (A) Selection operation. (B) Rename operation. (C) Join operation. (D) Projection operation.

Last Answer : (B) Rename operation.

Which of the following is true ? I. Implementation of self-join is possible in SQL with table alias. II. Outer-join operation is basic operation in relational algebra. III. Natural join and outer join operations are equivalent. (A) I and II are correct. (B) II and III are correct. (C) Only III is correct. (D) Only I is correct.

Description : Which of the following is true ? I. Implementation of self-join is possible in SQL with table alias. II. Outer-join operation is basic operation in relational algebra. III. Natural join and outer join operations are ... (B) II and III are correct. (C) Only III is correct. (D) Only I is correct.

Last Answer : (D) Only I is correct.

Consider a schema R(MNPQ) and functional dependencies M→N, P→Q. Then the decomposition of R into R1(MN) and R2(PQ) is ............. (1) Dependency preserving but not lossless join. (2) Dependency preserving and lossless join (3) Lossless join but not dependency preserving (4) Neither dependency preserving nor lossless join.

Description : Consider a schema R(MNPQ) and functional dependencies M→N, P→Q. Then the decomposition of R into R1(MN) and R2(PQ) is ............. (1) Dependency preserving but not lossless ... and lossless join (3) Lossless join but not dependency preserving (4) Neither dependency preserving nor lossless join. 

Last Answer : Answer: 1

Let R and S be two fuzzy relations defined as: Image Then, the resulting relation, T, which relates elements of universe x to elements of universe z using max-min composition is given by

Description : Let R and S be two fuzzy relations defined as: Then, the resulting relation, T, which relates elements of universe x to elements of universe z using max-min composition is given by

Last Answer : Answer: C

Consider an implementation of unsorted single linked list. Suppose it has its representation with a head and a tail pointer (i.e. pointers to the first and last nodes of the linked list). Given the representation, which of the following operation cannot be implemented in O(1) time ? (A) Insertion at the front of the linked list. (B) Insertion at the end of the linked list. (C) Deletion of the front node of the linked list. (D) Deletion of the last node of the linked list.

Description : Consider an implementation of unsorted single linked list. Suppose it has its representation with a head and a tail pointer (i.e. pointers to the first and last nodes of the linked list). Given the ... the front node of the linked list. (D) Deletion of the last node of the linked list.

Last Answer : (D) Deletion of the last node of the linked list. 

Consider the following schemas: Branch = (Branch-name, Assets, Branch-city) Customer = (Customer-name, Bank-name, Customer-city) Borrow = (Branch-name, loan-number, customer account-number) Deposit = (Branch-name, Account-number, Customer-name, Balance) Using relational Algebra, the query that finds customers who have balance more than 10,000 is ................. (A) πcustomer-name(σbalance> 10000(Deposit)) (B) σcustomer-name(σbalance> 10000(Deposit)) (C) πcustomer-name(σbalance> 10000(Borrow)) (D) σcustomer-name(σbalance> 10000(Borrow))

Description : Consider the following schemas: Branch = (Branch-name, Assets, Branch-city) Customer = (Customer-name, Bank-name, Customer-city) Borrow = (Branch-name, loan-number, customer account-number) Deposit = ... )) (C) πcustomer-name(σbalance> 10000(Borrow)) (D) σcustomer-name(σbalance> 10000(Borrow))

Last Answer : (A) πcustomer-name(σbalance> 10000(Deposit)) 

Suppose a customer table is having different columns like customer no, payments.What will be the query to select top three max payments?

Description : Suppose a customer table is having different columns like customer no, payments.What will be the query to select top three max payments?

Last Answer : SELECT customer_no, payments from customer C1 WHERE 3

Suppose there are four processes in execution with 12 instances of a Resource R in a system. The maximum need of each process and current allocation are given below: Image With reference to current allocation, is system safe? If so, what is the safe sequence? (A) No (B) Yes, P1 P2 P3 P4 (C) Yes, P4 P3 P1 P2 (D) Yes, P2 P1 P3 P4

Description : Suppose there are four processes in execution with 12 instances of a Resource R in a system. The maximum need of each process and current allocation are given below: With reference to current allocation, is system safe? If so, ... B) Yes, P1 P2 P3 P4 (C) Yes, P4 P3 P1 P2 (D) Yes, P2 P1 P3 P4

Last Answer : (C) Yes, P4 P3 P1 P2

Which of the following is a legal expression in SQL? (A) SELECT NULL FROM EMPLOYEE; (B) SELECT NAME FROM EMPLOYEE; (C) SELECT NAME FROM EMPLOYEE WHERE SALARY = NULL; (D) None of the above

Description : Which of the following is a legal expression in SQL? (A) SELECT NULL FROM EMPLOYEE; (B) SELECT NAME FROM EMPLOYEE; (C) SELECT NAME FROM EMPLOYEE WHERE SALARY = NULL; (D) None of the above

Last Answer : B) SELECT NAME FROM EMPLOYEE;

The statement in SQL which allows to change the definition of a table is (A) Alter. (B) Update. (C) Create. (D) select.

Description : The statement in SQL which allows to change the definition of a table is (A) Alter. (B) Update. (C) Create. (D) select

Last Answer : (A) Alter.

In a relational model, relations are termed as (A) Tuples. (B) Attributes (C) Tables. (D) Rows.

Description : In a relational model, relations are termed as (A) Tuples. (B) Attributes (C) Tables. (D) Rows.

Last Answer : (C) Tables

In the relational modes, cardinality is termed as: (A) Number of tuples. (B) Number of attributes. (C) Number of tables. (D) Number of constraints

Description : In the relational modes, cardinality is termed as: (A) Number of tuples. (B) Number of attributes. (C) Number of tables. (D) Number of constraints

Last Answer : (A) Number of tuples

What type of data is: a=[(1,1),(2,4),(3,9)]? a) Array of tuples b) List of tuples c) Tuples of lists d) Invalid type

Description : What type of data is: a=[(1,1),(2,4),(3,9)]? a) Array of tuples b) List of tuples c) Tuples of lists d) Invalid type

Last Answer : b) List of tuples

What is the output of the following code? >>> a=(2,3,4) >>> sum(a,3) a) Too many arguments for sum() method b) The method sum() doesn’t exist for tuples c) 12 d) 9

Description : What is the output of the following code? >>> a=(2,3,4) >>> sum(a,3) a) Too many arguments for sum() method b) The method sum() doesn’t exist for tuples c) 12 d) 9

Last Answer : c) 12

What is the output of the following piece of code when executed in Python shell? >>> a=("Check")*3 >>> a a) (‘Check’,’Check’,’Check’) b) * Operator not valid for tuples c) (‘CheckCheckCheck’) d) Syntax erro

Description : What is the output of the following piece of code when executed in Python shell? >>> a=("Check")*3 >>> a a) (‘Check’,’Check’,’Check’) b) * Operator not valid for tuples c) (‘CheckCheckCheck’) d) Syntax erro

Last Answer : c) (‘CheckCheckCheck’)

Which of the following statements is FALSE about weak entity set ? (A) Weak entities can be deleted automatically when their strong entity is deleted. (B) Weak entity set avoids the data duplication and consequent possible inconsistencies caused by duplicating the key of the strong entity. (C) A weak entity set has no primary keys unless attributes of the strong entity set on which it depends are included. (D) Tuples in a weak entity set are not partitioned according to their relationship with tuples in a strong entity set.

Description : Which of the following statements is FALSE about weak entity set ? (A) Weak entities can be deleted automatically when their strong entity is deleted. (B) Weak entity set avoids the data ... weak entity set are not partitioned according to their relationship with tuples in a strong entity set.

Last Answer : (D) Tuples in a weak entity set are not partitioned according to their relationship with tuples in a strong entity set.