DBMS MCQ questions and answers | DBMS questions PDF

Get all the latest most frequently asked DBMS(Database Management Systems) questions and answers in interview, aptitude(DBMS multiple choice questions and answers) and GATE exams.

01) A relational database consists of a collection of ____.

  1. fields
  2. tables
  3. records
  4. none of the above

Correct answer: tables

02) Which one of the below is a set of one or more attributes taken collectively to uniquely identify a record?

  1. public key
  2. super key
  3. foreign key
  4. None of the above

Correct answer: super key

03) Which language is used by a user to request information from a database?

  1. Relational
  2. Query
  3. Structural
  4. Compiler

Correct answer: Query

04) Which one of the below is used to define the structure of the relation, deleting relations and relating schemas?

  1. DML
  2. Query
  3. DDL
  4. None of the above

Correct answer: DDL(Data Definition Language)

05) The union operations is represented by

  1. %
  2. ^^
  3. U

Correct answer: U(Union operator combines the relations)

06) A delete command operates on _____relation.

  1. Two
  2. Several
  3. one
  4. Null

Correct answer: One(delete one table at a time)

07) Which of the below queries are useful in SQL update statements, where they can be used in the set clause?

  1. Sub queries
  2. Scalar subqueries
  3. update
  4. None of the above

Correct answer: Scalar subqueries

08) Which condition allows a general predicate over the relations being joined?

  1. set
  2. using
  3. on
  4. none of the above

Correct answer: ON(it gives the condition for the join expression)

09) Which of the below join operations do not preserve non-matched tuples?

  1. Inner join
  2. left outer join
  3. Right outer join
  4. None of the above

Correct answer: Inner join

10) Which of the below consists of a sequence of query & /or update statements?

  1. Commit
  2. Rollback
  3. Transaction
  4. none of the above

Correct answer: Transaction