In which database model is database item is viewed as a record with attributes?

DBMS MCQ's Question Set 1

Q.1. A relational database consists of a collection of

  1. Tables
  2. Fields
  3. Records
  4. Keys

Answer:- (1)

Q.2. Database __________ which is the logical design of the database, and the database _______ which is a snapshot of the data in the database at a given instant in time.

  1. Instance, Schema
  2. Relation, Schema
  3. Relation, Domain
  4. Schema, Instance

Answer:- (4)

Q.3. A domain is atomic if elements of the domain are considered to be ____________ units.

  1. Different
  2. Indivisbile
  3. Constant
  4. Divisible

Answer:- (2)

Q.4. Which one of the following is a set of one or more attributes taken collectively to uniquely identify a record?

  1. Candidate key
  2. Sub key
  3. Super key
  4. Foreign key

Answer:- (3)

Q.5. The subset of a super key is a candidate key under what condition?

  1. No proper subset is a super key
  2. All subsets are super keys
  3. Subset is a super key
  4. Each subset is a super key

Answer:- (1)

Q.6. The relation with the attribute which is the primary key is referenced in another relation. The relation which has the attribute as a primary key is called

  1. Referential relation
  2. Referencing relation
  3. Referenced relation
  4. Referred relation

Answer:- (2)

Q.7. The ______ is the one in which the primary key of one relation is used as a normal attribute in another relation.

  1. Referential relation
  2. Referencing relation
  3. Referenced relation
  4. Referred relation

Answer:- (3)

Q.8. Using which language can a user request information from a database?

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

Answer:- (1)

Q.9. Which one of the following is used to define the structure of the relation, deleting relations and relating schemas?

  1. DML(Data Manipulation Langauge)
  2. DDL(Data Definition Langauge)
  3. Query
  4. Relational Schema

Answer:- (2)

Q.10. Updates that violate __________ are disallowed.

  1. Integrity constraints
  2. Transaction control
  3. Authorization
  4. DDL constraints

Answer:- (1)

Q.11. This Query can be replaced by which one of the following?

SELECT name, course_id
   FROM instructor, teaches
   WHERE instructor_ID= teaches_ID;
  1. Select name,course_id from teaches,instructor where instructor_id=course_id;
  2. Select name, course_id from instructor natural join teaches;
  3. Select name, course_id from instructor;
  4. Select course_id from instructor join teaches;

Answer:- (2)

Q.12. Which of the following statements contains an error?

  1. Select * from emp where empid = 10003;
  2. Select empid from emp where empid = 10006;
  3. Select empid from emp;
  4. Select empid where empid = 1009 and lastname = ‘GELLER’;

Answer:- (4)

Q.13. By default, the order by clause lists items in ______ order.

SELECT name

FROM instructor
WHERE dept name = ’Physics’
ORDER BY name;

  1. Descending
  2. Any
  3. Same
  4. Ascending

Answer:- (4)

Q.14. The number of attributes in relation is called as its

  1. Cardinality
  2. Degree
  3. Tuples
  4. Entity

Answer:- (2)

Q.15. _________ joins are SQL server default

  1. Outer
  2. Inner
  3. Equi
  4. None of the mentioned

Answer:- (2)

Q.16. The predicate in a where clause can involve Boolean operations such as and. The result of true and unknown is_______ false and unknown is _____ while unknown and unknown is _____

  1. Unknown, unknown, false
  2. True, false, unknown
  3. True, unknown, unknown
  4. Unknown, false, unknown

Answer:- (4)

Q.17. Some of these insert statements will produce an error. Identify the statement.

CREATE TABLE employee (id INTEGER,name VARCHAR(20),salary NOT NULL);

INSERT INTO employee VALUES (1005,Rach,0);
INSERT INTO employee VALUES (1007,Ross, );
INSERT INTO employee VALUES (1002,Joey,335);

  1. Insert into employee values (1005,Rach,0);
  2. Insert into employee values (1002,Joey,335);
  3. Insert into employee values (1007,Ross, );
  4. None of the mentioned

Answer:- (3)

Q.18. Aggregate functions are functions that take a ___________ as input and return a single value.

  1. Collection of values
  2. Single value
  3. Aggregate value
  4. Both Collection of values & Single value

Answer:- (1)

Q.19. Aggregate functions can be used in the select list or the_______clause of a select statement or subquery. They cannot be used in a ______ clause.

  1. Where, having
  2. Having, where
  3. Group by, having
  4. Group by, where

Answer:- (2)

Q.20. How can you find rows that do not match some specified condition?

  1. EXISTS
  2. Double use of NOT EXISTS
  3. NOT EXISTS
  4. None of the mentioned

Answer:- (2)

DBMS MCQ's Question Set 2

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 Technical-MCQs For Placement Preparation

Best Gadgets for Engineers 

In which database model each database item is viewed as a record with attributes?

Relational model A particular attribute or combination of attributes is chosen as a primary key that can be referred to in other tables, when it's called a foreign key. Each row, also called a tuple, includes data about a specific instance of the entity in question, such as a particular employee.

Which data model is record based data model?

Relational model:- It is a viable data model based on records. Relational data models, network data models, and hierarchical data models are three examples of this sort of data model.

What are the 4 types of database models?

It demonstrates how data is organized and the various types of relationships that exist between them. The network Model, entity-relationship Model, hierarchical Model, object-oriented Model, and object Model are some of the different types of Database Models.

What is attributes as used in database?

In a database management system (DBMS), an attribute is a piece of data that describes an entity. For example, in a customer database, the attributes might be name, address, and phone number. In a product database, the attributes might be name, price, and date of manufacture.

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