Practice
Resources
Contests
Online IDE
New
Free Mock
Scaler Events New
Practice
Improve your coding skills with our resources
Contests
Compete in popular contests with top coders
Scaler
Explore Offerings by SCALER
Events
Checkout Scaler Academy Events
New

DBMS MCQ With Answers

What is a Database?

A database is an organized collection of data, general stores, and accessed electronically from a computer system.

What is DBMS?

The Database Management System(DBMS) is the software that interacts with end-users, applications, and the database itself to capture and analyze the data.

The DBMS software additionally encompasses the core facilities provided to administer the database. The sum total of the database, the DBMS, and the associated applications can be referred to as a “database system”.

Problems with File System

  • Data redundancy and inconsistency.
  • Difficulty in accessing data
  • Data isolation
  • Integrity problem
  • Atomicity problem
  • Concurrent access anomalies

Instance and Schemas

  • The collection of information stored in the database at a particular moment is called an instance of the database.
  • The overall design of the database is called the database schema.

Types of Databases

  • Commercial database
  • Multimedia database
  • Deductive database
  • Temporal database
  • Geological Info System

Characteristics of Database Management System

  • Provides security and removes redundancy
  • Self-describing nature of a database system
  • Insulation between programs and data abstraction
  • Support of multiple views of the data
  • Sharing of data and multiuser transaction processing
  • Database Management Software allows entities and relations among them to form tables.
  • It follows the ACID concept ( Atomicity, Consistency, Isolation, and Durability).

Learn More

What is Transaction?

  • To remove this partial execution problem, we increase the level of atomicity and bundle all the instructions of a logical operation into a unit called a transaction.
  • So, formally - ‘A transaction is a set of logically related instructions to perform a logical unit of work’.

What is a Schedule?

  • When two or more transactions are executed together or one after another, then they can be bundled up into a higher unit of execution called schedule.
  • A schedule of N transactions T1, T2, T3...TN, is an ordering of the operations of the transactions. Operations from different transactions can be interleaved in the scheduled S.
  • However, the schedule for a set of transactions must contain all the instructions of those transactions, and for each transaction T, that participates in the schedule S, the operation of T, in S must appear in the same order in which they occur in T.

Basics of RDBMS

  • The domain is a set of atomic values.
  • By atomic we mean that each value in the domain is indivisible as far as the formal relational model is concerned.
  • A common method of specifying a domain is to specify a data type from which the data forming the domain are drawn.
  • Table(Relation): A relation is a set of tupes/rows/entities/records.
  • Tuple: Each row of a relation/table is called a tuple.
  • Degree: Number of columns/attributes of a relation.
  • Cardinality: Number of rows/types/record of a relational instance.

Properties of RDBMS

  • Cells contain atomic values.
  • Values in a column are of the same kind.
  • Each row is unique.
  • Each column has a unique name
  • No two tables can have the same name in a relational schema.
  • The sequence of rows is insignificant.
  • The sequence of columns is insignificant.

Useful Resources

DBMS MCQs

Events | Powered By
1. 

Which of the following is the full form of DDL?

2. 

Which of the following is the property of transaction that protects data from system failure?

3. 

Which of the following is preserved in execution of transaction in isolation?

4. 

Which normalization form is based on the transitive dependency?

5. 

Which is the lowest level of abstraction that describes how the data are actually stored?

6. 

For performing tasks like creating the structure of the relations, deleting relation, which of the following is used?

7. 

What is rows of a relation known as?

8. 

Which of the following is a command of  DDL?

9. 

During transaction before commit which of the following statement is done automatically in case of shutdown?

10. 

Which of the following is the full form of TCL?

11. 

Which of the following SQL command is used for removing (or deleting) a relation form the database?

12. 

What is DBMS?

13. 

Rectangles in ER diagram represents?

14. 

Select the correct definition of relation.

15. 

Which of the following allows to uniquely identify a tuple?

16. 

Which of the following is known as minimal super key?

17. 

Select the relational algebra operations.

18. 

Which is AS clause used for?

19. 

How many levels are there in architecture of database?

20. 

Which data structure is used in Hierarchical model records?

21. 

How is ER diagram represented?

22. 

A relational database developer refers to a record as?

23. 

Which normal form deals with multivalued dependency?

24. 

Which of the following is not a SQL command?

25. 

Identify the concurrency based protocol?

26. 

Select the correct foreign key constraint?

27. 

What is the name of the query that is placed within a WHERE or HAVING clause of another query?

28. 

Which command is used to remove a stored function from the database?

29. 

After which operation is the modify operation done?

30. 

Which of the following command is used to change data in table?

31. 

Which of the following normal forms contains information about a single entity?

32. 

Which of the following can replace the below query?

SELECT name, course_id  
FROM instructor, teaches  
WHERE instructor_ID= teaches_ID;  
 

33. 

Which of the following is the full form of NTFS?

34. 

What is the number of tuples of a relation known as?

35. 

Select the correct definition of Relational calculus?

36. 

Total view of a database is known as?

37. 

Select the definition of the correct key which is used to represent relation between two tables?

38. 

Select the correct command to find the number of values in a column.

39. 

Select the correct command to modify a column in a table.

40. 

Select the correct properties of entities?

41. 

Primary key can be?

42. 

To select some particular columns, which of the following command is used?

43. 

Select the correct database object which does not exist physically.

44. 

NATURAL JOIN can also be termed as -

45. 

Which of the following operator is used to compare a value to a list of literals values that have been specified?

46. 

Maximum children of  a B-tree of order m?

47. 

What is a table joined with itself called?

48. 

What is the use of COUNT in SQL?

49. 

Select the valid SQL type.

50. 

Select the correct advantages of view.

Get Placed at Top Product Companies with Scaler Know More 
Get Placed at Top Product Companies with Scaler Know More 
Get Placed at Top Product Companies with Scaler
Sat transparent 640a34d454880bf68e3bfdf33f2389f2214043f59ad18b4c7f7b114e834fb257.svg

Point markers b3add1cc88e4996b2df6e0aedb9f0d1b65fa73c51b7ada8fbee3895a2aa11802.svg Personalised feedback report with solutions
Point markers b3add1cc88e4996b2df6e0aedb9f0d1b65fa73c51b7ada8fbee3895a2aa11802.svg Real life Interview Questions
Point markers b3add1cc88e4996b2df6e0aedb9f0d1b65fa73c51b7ada8fbee3895a2aa11802.svg Identify exact topics to improve

Your feedback is important to help us improve.
Free Mock Assessment
Fill up the details for personalised experience.
All fields are mandatory
Current Employer *
Enter company name *
Graduation Year *
Select an option *
1992
1993
1994
1995
1996
1997
1998
1999
2000
2001
2002
2003
2004
2005
2006
2007
2008
2009
2010
2011
2012
2013
2014
2015
2016
2017
2018
2019
2020
2021
2022
2023
2024
2025
2026
2027
Phone Number *
OTP will be sent to this number for verification
+1 *
+1
Change Number
Phone Number *
OTP will be sent to this number for verification
+1 *
+1
Change Number
Graduation Year *
Graduation Year *
1992
1993
1994
1995
1996
1997
1998
1999
2000
2001
2002
2003
2004
2005
2006
2007
2008
2009
2010
2011
2012
2013
2014
2015
2016
2017
2018
2019
2020
2021
2022
2023
2024
2025
2026
2027
*Enter the expected year of graduation if you're student
Current Employer *
Company Name *
Please verify your phone number
Edit
Resend OTP
By clicking on Start Test, I agree to be contacted by Scaler in the future.
Already have an account? Log in
Free Mock Assessment
Instructions from Interviewbit
Start Test