DBMS MCQ | Database Management System MCQs for Freshers

Posted on: | By: – Comments Off

Database Management System MCQs

Top 50 DBMS mcq questions and answers focuses on all areas of Database Management System subject covering all the topics in Database Management System.

 

1) A change in the order of the tables given in a query will have an impact in the final result-set of the query.

  1. TRUE
  2. False
Answer : B

 

2) A collection of related data fields is called a ____.

  1. byte
  2. record
  3. character
  4. bit
Answer : B

 

 

3) A DBMS is a(n) ____.

  1. interface between the database and application programs
  2. data repository
  3. knowledge base
  4. unique group of records
Answer : A

 

 

4) A FLAT FILE database management system is

  1. A database design that only has one table in it
  2. A DBMS that can only have simple data tables in it
  3. A DBMS that can only have one table in it
  4. A DBMS that contains records that have a large number of fields in them
Answer : C

 

 

5) A primary Key column should have

  1. Unique values but can contain NULL
  2. Unique values and can’t contain NULL
  3. May not contain Unique values but shouldn’t have NULL
  4. May not contain Unique values and can contain NULL.
Answer : B

 

 

6) A Table

  1. Can only store data of one type
  2. Consists of Alphanumeric data
  3. Consists of Rows and Columns
  4. Cannot be empty
Answer : B

 

 

7) A table can have only one PRIMARY KEY

  1. True
  2. FALSE
Answer : A

 

 

8) A table can’t have more than one UNIQUE KEY

  1. TRUE
  2. False
Answer : B

 

 

9) Ability of a computer system or a database to operate efficiently with larger quantities of data is called

  1. Linearity
  2. Feasibility
  3. Scalability
  4. Efficiency
Answer : C

 

 

10) All the locks are released when

  1. we issue a commit statement
  2. when we issue a rollback statement
  3. both a and B are true
  4. none of them is true
Answer : C

 

 

11) An Empty string and null are both the same

  1. TRUE
  2. False
Answer : B

 

 

12) Can you use select in FROM clause of SQL select ?

  1. YES
  2. NO
Answer : A

 

 

13) Column alias cant be used in which clause

  1. Select
  2. where
  3. Order by
  4. none
Answer : D

 

 

14) Commit command is used to make the changes permanent in the table

  1. True
  2. FALSE
Answer : A

 

 

15) Consider the table (STUDREC). Which of the following statements will list columns INIT, SNAME, GENDER and KIDS (in that order) for all students who have more then 1 child.

  1. SELECT init, sname, gender, kids FROM studrec WHERE kids <1;
  2. SELECT init, sname, gender, kids FROM studrec WHERE kids >1;
  3. SELECT init, sname, gender, kids FROM studrec WHERE kids >’1′;
  4. SELECT init sname, gender, kids FROM studrec WHERE kids >1;
Answer : D

 

 

16) CREATE TABLE statement is used to create

  1. Both relational table and object table
  2. Only relational table
  3. Only object table
  4. XML Table
Answer : A

 

 

17) CREATE TABLE table_name(column_name CHAR);                                                                             The above SQL statement will create table table_name

  1. True
  2. FALSE
Answer : A

 

 

18) Database schema is implemented from

  1. Conceptual Data Model
  2. Logical Data Model
  3. Physical Data Model
  4. Metadata model
Answer : C

 

 

19) DBMS is the acronym for

  1. Directory Base Management System
  2. Database Master System
  3. Data Basic Management System
  4. Database Management System
Answer : D

 

 

20) Describe the use of %ROWTYPE in PL/SQL ?

  1. It allows you to associates a variable with a single column type
  2. It allows you to associate a variable with an entire table row
  3. It allows you to associate a variable with an entire table column
  4. Both A and C
Answer : B

 

 

21) Distinct Keyword is used for

  1. Selecting all duplicate rows
  2. Eliminating all duplicate rows from the output
  3. Both A & B
  4. None of the above
Answer : B

 

 

22) Domain is

  1. Number of attributes
  2. Tuple
  3. A pool of values from which specific attributes of specific relations draw their values
  4. None of the above
Answer : C

 

 

23) Foreign Key

  1. may contain NULL
  2. has unique values
  3. Either A or B
  4. None of the above
Answer : A

 

 

24) GROUP BY SQL clause

  1. Uniquely lists the aggregated
  2. items in the SELECT list
  3. Uniquely lists the unaggregated
  4. items in the SELECT list
  5. Nonuniquely lists the unaggregated
  6. items in the SELECT list
  7. Nonuniquely lists the aggregated
  8. items in the SELECT list
Answer : B

 

 

25) How does a database store data about its tables?

  1. By a data dictionary
  2. By entity modeling
  3. By normalization
  4. By relationships
Answer : A

 

 

26) IF I want to store true / false in sql values from my frontend which data type should I use at the best level in terms of minimum storage?

  1. Char
  2. Varchar
  3. Bit
  4. Int
Answer : C

 

 

27) In Ascending order sort null values appear in the bottom of the result set

  1. True
  2. FALSE
Answer : A

 

 

28) In the relational database terminology, a table is synonymous with:

  1. A column
  2. A row
  3. An attribute
  4. A relation
Answer : D

 

 

29) Insert, Drop table are examples of which SQL type?

  1. DML
  2. DDL
  3. None of the above
Answer : B

 

 

30) Managing data security involves

  1. Data Classification
  2. Encryption
  3. Data Governance
  4. all of the above
Answer : D

 

 

31) One of the goals of a DBMS is to increase data redundancy thereby making it less vulnerable to hackers.

  1. TRUE
  2. False
Answer : B

 

 

32) Rollback is used to reach the previous committed state

  1. True
  2. FALSE
Answer : A

 

 

33) SELECT * FROM R1 LEFT [OUTER] JOIN R2 ON R1.field = R2.field

– returns additional rows from?

  1. R1
  2. R2
  3. Both
  4. Neither
Answer : A

 

 

34) select, update are examples of which SQL type

  1. DML
  2. DDL
  3. None of the above
Answer : A

 

 

35) SQL stands for

  1. Sequential Question Language
  2. Structured Query Language
  3. Structured Question Language
  4. Sequential Query Language
Answer : B

 

 

36) Table partitioning splits the storage of a table into smaller individual units.

  1. True
  2. FALSE
Answer : A

 

 

37) To improve performance, all tables in the data warehouse should be indexed.

  1. TRUE
  2. False
Answer : B

 

 

38) Union All returns

  1. All rows selected by either query
  2. All rows selected by either query and including duplicates
  3. All distinct rows selected by both queries
  4. All rows selected by the first query but not the seconds
Answer : B

 

 

39) Unique Constraint enforces

  1. single number value to be entered
  2. single character to be entered
  3. multiple values in set of columns
  4. uniqueness of the values
  5. in a set of columns
Answer : D

 

 

40) User-Defined Integrity enforces

  1. null constraints
  2. some specific business
  3. rules
  4. check constraints
  5. entity integrity
Answer : B

 

 

41) What is a formal way to express data relationships to a database management system?

  1. Attributes
  2. Entity identifier
  3. Data model
  4. Entity-relationship diagram
Answer : C

 

 

42) What is Database ?

  1. A known fact that can be recorded and that have implicit meaning
  2. The data is perceived by the user as tables
  3. It is designed, built, and populated with data for a specific purpose
  4. All of the above
Answer : C

 

 

43) What is the default ordering of an ORDER BY clause in a SELECT statement?

  1. Descending
  2. Ascending
Answer : B

 

 

44) Which clause limits the rows selected in a query?

  1. Order By
  2. Where
  3. Select
  4. From
Answer : B

 

 

45) Which is a feature of RDBMS?

  1. Create multiple tables and enter data into them
  2. Interactive Query language
  3. All of these
  4. Retrieval of data stored in more than on table
Answer : C

 

 

46) Which of the following are elements of SQL?

  1. Data Control Language
  2. Data Definition Language
  3. Data Manipulation Language
  4. All of these
Answer : D

 

 

47) Which of the following statements does not apply to relational databases?

  1. Relational databases are simple to understand
  2. Tables are one of the basic components of relational databases
  3. Relational databases have a strong procedural orientation
  4. Relational databases have a strong mathematical foundation
Answer : C

 

 

48) Which one is DDL command?

  1. Insert
  2. Update
  3. Drop
  4. Select
Answer : C

 

 

49) Which part of the following SQL is responsible for not returning the expected output? Select * from emp where comm = null order by ename;

  1. order by clause should appear before where clause
  2. where comm = null
  3. we cant use select * here
  4. No error
Answer : B

 

 

50) Why is denormalization beneficial to read operations?

  1. Indexes are sorted.
  2. Disk I/O is reduced.
  3. complex joins is avoided
  4. Easy Data flow
Answer : C

 

51) DML is provided for

  1. Description of logical structure of database
  2. Addition of new structures in the database system
  3. Manipulation & processing of database
  4. Definition of physical structure of database system
Answer : C