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TN State Board 12th Computer Applications Important Questions Chapter 3 Introduction to Database Management System

Question 1.
Write a any two notable features of good DBMS.
Answer:

• Giving protection to data.
• User-friendly for users are notable features of good DBMS.

Question 2.
What will be provides by DBMS?
Answer:
The DBMS provides users and programmers with a systematic way to create, retrieve, update and manage data.

Question 3.
What are various access methods in file system?
Answer:
The various access methods in file system were indexed, Random and sequential access.

Question 4.
What is mean by Data Duplication?
Answer:
Data Duplication mean, same data is used by multiple resources for processing, thus created copies of same data wasting the spaces.

Question 5.
What is Atomicity?
Answer:
An Atomicity follows the thumb rule “All or Nothing”, while updating the data in database for the user performing the update operation.

Question 6.
What is called update operation?
Answer:
The update operation is called as transaction and it either commits or aborts.

Question 7.
What is consistency?
Answer:
Consistency ensures that the changes in data value to be constant at any given instance. This property helps in the successful transaction.

Question 8.
What is known as concurrent Transactions?
Answer:
When multiple users do the transactions by accessing same object at the same time, the transaction is known as concurrent transaction.

Question 9.
What is Durability?
Answer:
Durability is defined as the system’s ability to recover all committed transactions during the failure of storage or the system.

Question 10.
What is Hierarchical Database Model?
Answer:
The Hierarchical Database Model was IMS (Information Management System), In this model each record has information in parent/child relationship like a tree structure.

Question 11.
What is advantage and Disadvantage of Hierarchical Database Model?
Answer:
Hierarchical Database Model have many advantages like less redundant data, efficient search, data integrity and security.
Disadvantage of this model has few limitations like complex to implement and difficultly in handling many to many relationships.

Question 12.
What is Network database Model?
Answer:
Network database model is similar to Hierarchical model except that in this model each member can have more than one owner. The many to many relationship are handled in a better way.

Question 13.
What are three database components identified by Network model?
Answer:
Network model identified the three database components, Network schema, Sub schema, and Language for data management.

Question 14.
What is major advantage and limitation of Network Model?
Answer:
The Major advantages of this model is the ability to handle more relationship types, easy data access, data integrity and Independence.
The limitation of network model is difficulty in design and maintenance.

Question 15.
Define Relational Model.
Answer:
Relational model is defined with two terminologies Instance and schema.

Question 16.
What are incorporates the object-oriented database model?
Answer:
The Object-oriented database model incorporates the combination of Object Oriented Programming (OOP’s) concepts and database technologies.

Question 17.
Define two terminologies of Relational Model.
Answer:
The two terminologies of Relational Model are

• Instance – A table consisting of rows and columns.
• Schema – Specifies the structure including name and type of each column.

Question 18.
What are advantage of object – oriented database model?
Answer:

• The object-oriented database model efficiently manages large number of different data types.
• Moreover complex behaviours are handled efficiently using OOP’s concepts.

Question 19.
What is known as Relational Database?
Answer:
Any database whose logical organization is based on relational data model is known as relational database.

Question 20.
What are basic RDBMS concept?
Answer:
The basic RDBMS concept includes Database, Tables, Tuple, Attribute, Schema, and Key.

Question 21.
What is a Table?
Answer:
A table is the simple representation of relations. The true relations cannot have duplicate rows where as the table can have.

Question 22.
What is a Column?
Answer:
Table can be divided into smaller parts, in terms of column. Each column is known a.s Attributes.

Question 23.
What is a Row?
Answer:

• A single entry in a table is called as Row. Set of related data’s are represented in a row or tuple.
• The Horizontal entity in a table is known as row or Record.

Question 24.
What is a primary key?
Answer:
A primary key is a special relational database table column designated to uniquely identify all table records.

Question 25.
What is a secondary key?
Answer:
An entity may have one or more choices for the primary key. One is selected as the primary key.
Those not selected are known as secondary keys.

Question 26.
What is composite Primary Key?
Answer:
A Primary Key which is a combination of more than one attribute is called a Composite Primary Key.

Question 27.
What is Foreign Key?
Answer:
A Foreign Key is a copy of the whole of its parent primary key.
Foreign Key values do not have to be unique. Foreign Keys can also be null.

Question 28.
What is super key?
Answer:
An attribute or group of attributes, which is sufficient to distinguish every tuple in the relation from every other one is known as super key.

Question 29.
What is Composite or Compound Key?
Answer:
A Key with more than one attribute to identify rows uniquely in a table is called composite key. This is also known as compound key.

Question 30.
What are basic concepts of ER Model?
Answer:

• Entity or Entity type
• Attributes
• Relationship

Question 31.
What is an Entity?
Answer:
An Entity can be anything a real-world object or animation which is easily identifiable by anyone even by a common man.

Question 32.
What are types of Entity?
Answer:

• Strong Entity,
• Weak Entity,
• Entity Instance.

Question 33.
What is strong Entity?
Answer:
A strong entity is the one which does not depend on any other entity on the schema or database and a strong entity will have a primary key with it.

Question 34.
What is Weak Entity?
Answer:
A Weak Entity is dependent on other entities and it does not have any primary key.

Question 35.
What is Instance?
Instance are the values for the entity.

Question 36.
What is Attribute?
Answer:
An attribute is the information about that entity and it will describe, quantify, qualify, classify, and specify and entity.

Question 37.
What is key Attribute?
Answer:
A key attribute describes a unique characteristic of an entity.

Question 38.
What is Simple Attribute?
Answer:
The simple attributes cannot be separated it will be having a single value for their entity.

Question 39.
What is Composite Attributes?
Answer:
The Composite Attributes can be sub divided into simple attributes without change in the meaning of that attribute.

Question 40.
What is single valued Attributes?
Answer:
A single valued attribute contains only one value for the attribute and they don’t have multiple numbers of values.

Question 41.
What is Multi valued Attributes?
Answer:
A Multivalued attribute has more than one value for that particular attribute.

Question 42.
What are components of ER Diagram?
Answer:
The components of ER Diagram are Entities, Attributes and Relationship.

Question 43.
Who was founded MySQL?
Answer:
MySQL is a database management system founded by Monty Widenius and is named after his daughter name My.

Question 44.
What are responsible have Database Administrator?
Answer:
Database Administrator (DBA), who takes care of Configuration, Installation, Performance, Security and Data Backup.

Question 45.
What are the skills needed by Database Administrator (DBA’s)?
Answer:
DBA’s posses the skills’on database design, database queries, RDMS, SQL and networking.

Question 46.
Write the types of software tools in the market to design the database.
Answer:
Many open source tools are available in the market to design the database in a better and efficient manner.
PhPMyAdmin is a most popular for web Administration. The Popular Desktop Application tools are MySQL workbench and HeidiSQL.

Question 47.
What is known as Designing of databases?
Answer:
The process of creating, implementing and maintaining the enterprise data in a system is known as Designing of databases.

Question 48.
Write the SQL DCL commands.
Answer:

• Grant – Used to give permission to specific users on specific databases.
• Revoke – Used to take out permission from specific users on specific databases.

Question 49.
Write the syntax and example for sort the records in SQL.
Answer:
Syntax:
SELECT*FROM tablename ORDER BY columnname ASC/DESC;
Eg: SELECT*FROM studentdb ORDER ‘EY stadName ASC;

Question 50.
Write the example for subquery in SELECT statement.
Answer:
Eg: SELECT*FROM studentdb WHERE studID
IN (SELECT studID FROM studentdb WHERE class = 12) ;

Question 51.
What is the DBMS mechanism used for data sharing?
Answer:

• Concurrency control and Locking is the DBMS’s mechanism used for data sharing.
• When the same data is shared among multiple users, proper access control is needed and privilege of changing the application data item is controlled through locking.

Question 52.
List the types of Attributes.
Answer:

1. Key Attribute
2. Simple Attribute
3. Composite Attribute
4. Single Valued Attribute
5. Multi Valued Attribute

Question 53.
Write the attributes of Few entity an example of ER diagram.
Answer:
The attributes of few entity of parent, student and Teacher are
Parent – Name, Id, FName, LName
Student – Id, Name, FName, LName
Teacher – Name, Id, Phone, Address

Question 54.
List the some commonly used Databases.
Answer:

1. DB2
2. MySQL
3. Oracle
4. PostgreSQL
5. SQLite
6. SQLServer
7. Sybase

Question 55.
Write short note on create conceptual Design.
Answer:

1. Create conceptual Design is the primary in database design, where detailed discussion about the creation of databases, tables, columns and data types is discussed based on the requirement of the application.
2. As an end result the model is framed to attain the expectation of the application’s end user.
3. MySQL provides performance dashboard, reports nad statistics regarding the design of database.

Question 56.
Explain the three major parts that create databases.
Answer:
The three major parts that forms a database are Tables, Queries and views.

1. Tables: It Similar to an excel sheet containing multiple rows and columns.
2. Queries: It is a question with multiple conditions posted to the database.
3. Views: A set of stored queries.

Question 57.
Write the SQL DDL commands.
Answer:
The SQL DDL (Data Definition Language) commands are:

• CREATE – Used to create database or table.
• ALTER – Modifies the existing structure of database or table.
• DROP – Deletes a database or table.
• RENAME – Used to rename an existing object in the database.
• TRUNCATE – Used to delete all table records.

Question 58.
Write the SQL DML commands.
Answer:
The SQL DML (Data Manipulation Language) commands are

• INSERT – Add new rows into database table.
• UPDATE – Modifies existing data with newdata within a table.
• DELETE – Deletes the records from the table.

Question 59.
Write the SQL TCL commands.
Answer:
The SQL TCL (Transaction Control Language) commands are

• COMMIT – Permanent save into database
• ROLLBACK – Restores database to original form.
• SET TRANSACTION – Set the transaction properties such as read-write or read only access.
• SAVE POINT – Used to temporarily save a transaction.

Question 60.
Write a syntax and example to delete a existing record from the table using delete command with where condition.
Answer:
Syntax:
DELETE FROM tablename WHERE columnname = “Value”;
Eg 1:DELETE FROM’ studentdb WHERE’Rollno = “121008”;
Eg 2:DELETE FROM studentdb;
Eg 1: is to delete a record with rollno 121008 only
Eg 2 :is to delete a table as studentdb

Question 61.
Write the MySQL operators.
Answer:

• Arithmetic Operators: +, -, *, /, ÷
• Comparison Operators: =, !=, <, >, < >, >=, <=
• Logical Operators: AND, ANY, BETWEEN, EXISTS, IN, LIKE, NOT, OR, UNIQUE

Question 62.
What are the rules should follow in sub Queries.
Answer:

1. Sub Queries are always written within the parantheses.
2. Always place the subquery on the right side of the comparison operator.
3. ORDER BY clause is not used in subquery, since subqueries cannot manipulate the results internally.

Question 63.
Write the three database components of network model.
Answer:
The three database components of network model are

• Network schema: This schema defines all about the structure of the database
• Sub schema: It controls on views of the database for the user
• Language: Basic procedure for accessing the database

Question 64.
Write the features of RDBMS.
Answer:

1. High availability
2. High performance
3. Robust Transactions and support
4. Ease of management
5. Less cost

Question 65.
Explain ER model relationship type.
Answer:
Three types of relationships are available and the Entity-Relationship(ER) diagram is based on the three types listed below.

One-to-One relationship:
Consider two entities A and B. One-to-one (1:1) relationship is said to exist in a relational database design, if 0 or 1 instance of entity A is associated with 0 or 1 instance of entity B, and 0 or 1 instance of entity B is associated with 0 or 1 instance of entity A.

One-to-Many relationship:
Consider two entities A and B. One-to-many (1 :N) relationship is said to exist in a relational database design, for 1 instance of entity A there exists 0 or 1 or many instances of entity B, but for 1 instance of entity B there exists 0 or 1 instance of entity A.

Many-to-Many relationship:
Consider two entities A and B. Many-to- many (M:N) relationship is said to exist in a relational database design, for 1 instance of entity A there exists 0 or 1 or many instances of entity B, and for 1 instance of entity B there exists 0 or 1 or many instance of entity A.

In reality one-to-one are in less usage, where as one-to-many and many-to- many are commonly used. However in relational databases, many-to-many are converted into one-to-many relationships.

Question 66.
Write the ER diagram Notations.
Answer:

Question 67.
Write about MySQL.
Answer:

1. MySQL is a database management system founded by Monty Widenius and named after his daughter name My.
2. Definition of database and SQL is mandatory to understand MvSOL.
3. A database is defined as the structured collection of data. Eg: Photo gallery is a database which has collection of photos (data).
4. SQL – Structured Query Language is not a database. It is a standardized language used to access the database and the data’s are processed to turn into efficient information.
5. MySQL is open source software that allows managing relational databases.
6. MySQL also provides the flexibility of changing the source code as per the needs.
7. MySQL runs on multiple platforms like windows, Linux and is scalable, reliable and fast.
8. MySQL is the most commonly used database in the world due to its ease of use.

Question 68.
Draw a ER – diagram by parent, student and teacher.
Answer:

Question 69.
Explain the newly create user account to MySQL.
Answer:

1. In MySQL database, there exists a table named user. The newly created account must have an entity in this user table.
2. The Admin creates an account with username and password.
3. The user account is activated with various access rights like INSERT, SELECT and UPDATE.
4. The user table has the following fields host, name, password, select_ priv, insert_priv and update_priv.
5. A new user account is added with values to the user table using.
   MySQL> INSERT INTO user (host, name, password,
   select_priv, insert_priv, update_priv) VALUES (‘localhost’, ‘guest’, PASSWORD (‘abcl23’), ‘Y’, ‘Y’, ‘Y’);
   then, mysql>FLUSH PRIVILEGES; This command is executed after every new account creation. This command is similar to rebooting the server, so that newly created account and the access privilege are updated in this server.

Question 70.
How can you install in MySQL in your computer?
Answer:
(i) Download and install XAMPP server software from Internet. Click the welcome page next button.
(ii) Select the required component along with MySQL component and click next button. Choose, the installation folder and click next button.
(iii) Click Next button in setup ready page. Installation get started.
(iv) After Installing click finish button and open the XAMMP control panel.

(v) In the control panel start the Apache and MySQL services one by one.
(vi) Now open URL http: //local host/PhPMyAdmin URL in a browser to access MySQL database.

Question 71.
Define Data Model and list the types of data model used.
Answer:

1. A data model is an abstract model that organizes elements of data and standardizes how they relate to one another and to properties of the real world entities.
2. The types of data model are Hierarchical database model, Network model, Relational model, object – Oriented database model.

Question 72.
List few disadvantages of file processing system.
Answer:

1. Duplicate data
2. Inconsistency
3. Accessing anomalies
4. Poor data integrity
5. Poor data security
6. Atomicity problem
7. Wastage of labor and space
8. Data isolation

Question 73.
Define Single and multi valued attributes.
Answer:

• A single valued attribute contains only one value for the attribute.
  Eg: Age – It is a single value for a person.
• A multi valued attribute has more than one value for that particular attribute.
  Eg: Degree – A person can hold number of degrees.

Question 74.
List any two DDL and DML commands with its Syntax.
Answer:
Two DDL (Data Definition Language) commands.
(i) CREATE:
Syntax:
Create database databasename;

(ii) DROP
Syntax:
Drop database database name;

Two DML (Data Manipulation Language) command.
(i) INSERT:
Syntax:
INSERT INTO tablename (columnl, column2, column3)
VALUES (valuel, value2, value3);

(ii) DELETE:
Syntax:
DELETE from tablename WHERE columnname = “value”;

Question 75.
What are the ACID properties?
Answer:
ACID properties are Atomicity, Consistency, Isolation and Durability.

Question 76.
Which command is used to make permanent changes done by a transaction?
Answer:

• The SQL commands manage the transactions in SQL databases.
• It also help to save the change into database permanently.
• COMMIT, ROLLBACK, SET TRANSACTION and SAVEPOINT commands belongs to this category.

Question 77.
What is view in SQL?
Answer:

• View in SQL can be described as virtual table which derived its data from one or more than one table columns.
• It is stored in the database.
• View can be created using tables of same database or different database.

Question 78.
Write the difference between SQL and MySQL.
Answer:

Question 79.
What is Relationship and List its types.
Answer:

1. Relationships are very similar in that they are associations between tables.
2. There exists a relationship between two tables when the foreign key of one table references primary key of other table.
3. Its types are one-one-relationship, One-to-many relationship and many- to-many relationship.

Question 80.
State few advantages of Relational databases.
Answer:

1. High Availability
2. High Performance
3. Robust Transactions and Support
4. Ease of Management
5. Less Cost

Question 81.
Explain on Evolution of DBMS.
Answer:

1. Data Base Management System (DBMS) is system software for creating and managing databases.
2. The concept of storing the data started before 40 years in various formats.
3. In earlydays they have used punched card technology to store the data. Then files were used. The file systems were known as predecessor of database system.
4. Various access methods in file system were indexed, random and sequential access.
5. The file system had more limitations like data duplication, high maintenance and security.

Question 82.
What is relationship in databases? List its types.
Answer:

1. Relationships are very similar in that they are associations between tables in database.
2. There exists a relationship between two tables when the foreign key of one table references primary key of other table.
3. List of the database types are one-one-relationship, One-to-many relationship and Many-to-many relationship.

Question 83.
Discuss on cardinality in DBMS.
Answer:
Cardinality is defined as the number of items that must be included in a relationship. That is number of entities in one set mapped with the number of entities of another set via relationship. Three caissifications in cardinality are One-to-one, One-to-many and Many-to-many.

Eg 1:

This cardinality is one-to-one re1atinship between person and vehicle.

Eg 2:

This cardinality relation is a one-to-many

Eg 3:

This cardinality relation is a n to n i.e., Many-to-many relationship.
A student can register many courses, A course can be registered by many students.

Question 84.
List any 5 privileges available in MySQL for the User.
Answer:

Question 85.
Write few commands used by DBA to control the entire database.
Answer:
The Database Administrator (DBA) frequently uses few commands to control the entire database. Such commands are.
(i) Use Database:
This commands is used to select the database in MySQL for working.
Syntax: Mysql > Use Student;

(ii) Show Databases:
Lists all the databases available in the database server.
Syntax: Mysql > Show databases;

(iii) Show columns from tablename:
List all the attributes, attribute type, IS NULL value permitted, key information for the given table.
Syntax: Mysql > Show columns from Rollnumber;

(iv) Show tables:
List all the tables available in the current database.
Syntax: Mysql > Show tables;

(v) Show index from tablename:
The query shows all the indexes for the given table.
Syntax: Mysql > Show indexes from student;

Question 86.
Discuss on various database models available in DBMS.
Answer:
The various database models in DBMS are Hierarchical Database Model, Network Model, Relational Model, and Object-oriented database Model.
(i) Hierarchical Database Model:
The Hierarchical database model was IMS (Information Management System), and IBM’s First DBMS.
In this model each record has information in parent/child relationship like a tree structure.

(ii) Network Model:
The first developed network data model was IDS (Integrated Data Store) at Honeywell.
Network model is similar to Hierarchical model except that in this , model each member can have more than one owner. The many to many relationships are handled in a better way.
This model identified the three database components Network schema, Sub schema and language for data management.

(iii) Relational Model:
Oracle and DB2 are few commercial relational model in use.
Relational model is identified with two terminologies Instance and schema.

(iv) Object-Oriented database model:
This model incorporates the combination of object oriented programming (OOP’s) concepts and database technologies.
This Model efficiently manages large number of different data types. Moreover complex behaviours are handled efficiently using OOP’s concepts.

Question 87.
List the basic concepts of ER Model with suitable example.
Answer:
The basic concepts of ER model consists of
(i) Entity or Entity type
(ii) Attributes
(iii) Relationship

(i) Entity or Entity type:
An Entity can be anything a real-world object or animation which is easily identifiable by anyone even by a common man.
Eg: In a company’s database Employee, HR, Manager are considered as entities, where each of these entity will be having their own attributes. An entity is represented by a rectangular box

The types of Entity are strong entity, weak entity, and Entity instance.

(ii) Attributes:
An attribute is the information about that entity and it will describe, quantity, qualify, classify, and specify an entity.
Types of attributes:
(a) Key Attribute – Eg: A key
(b) Simple Attribute – Eg: Employee
(c) Composite Attribute – Eg: Name
(d) Single Valued Attribute – Eg: Age
(e) Multi Valued Attribute – Eg: Degree

(iii) Relationship:
Three types of relationships are available, they are One- to-one relationship, One-to-many relationship and Many-to-many relationship.
Three classifications in cardinality are One-to-one, One-to-many and Many-to-many.
Eg: A driver drives a vehicle, this is One-to-one relationship between person and vehicle.
Eg: A customer places the order of many items, this is a One-to-many relationship.
Eg: Courses can be registered by many students, this is a many-to-many relationship.

Question 88.
Discuss in detail on various types of attributes in DBMS.
Answer:
The various types of attributes in DBMS are:
(i) Key Attribute
(ii) Simple Attribute
(iii) Composite Attribute
(iv) Single valued Attribute
(v) Multivalued Attribute

(i) Key Attribute:
A key attribute describes a unique characteristic of an entity.

(ii) Simple Attribute:
The Simple attributes cannot be separated it will be having a single value for their entity.

Eg: Here, the name as the attribute for the entity employee and here value for that attribute is a single value.

(iii) Composite Attribute:
The composite attributes can be sub divided into simple attributes without change in the meaning of that attribute.
Eg: In the above diagram, the composite attribute name which are sub¬divided into two simple attributes first and last name.

(iv) Single valued Attributes:
A single valued attribute contains only one value for the attribute and they don’t have multiple numbers of values.

Eg: Age – It is single value for a person.

(v) Multivalued Attributes:
A multi valued attribute has more than one value for that particular attribute.
Eg: Degree – A person can hold number of degrees, so it is multivalued attribute.

Question 89.
Write a note on open source software tools available in MySQL Administration.
Answer:
Many open source tools are available in the market to design the database in a better and efficient manner.
PhpMy Admin is most popular for web administration.
The popular desktop application tools are MySQL workbench and HeidiSQL.

PHPMYADMIN (Web Admin):
This Administrative tool of MySQL is a web application written in PHP. They are used predominantly in web hosting. The main feature is providing web interface, importing data from CSV and exporting data to various formats.

MySQL workbench (Desktop Application):
This is a database tool used by developers and DBA’s mainly for visualization.
This tool helps in data modeling, development of SQL, server configuration and backup for MySQL in a better way.
The SQL editor of this tool is very flexible and comfortable in dealing multiple results set.

HeidiSQL (Desktop Application):
This is open source tools helps in the administration of better database systems.
It supports GUI (Graphical User Interface) features for monitoring server host, server connection, Databases, Tables, Views, Triggers ami Events.

Question 90.
Explain in detail on Sub Queries with suitable examples.
Answer:
The SQL query is written within a main query. This is called as nested inner/ subquery. The subquery is executed first and the results of sub query are used as the condition for main query.
The sub query must follow the below rules:
(i) Subqueries are always written within the parantheses.
(ii) Always place the subquery on the rightside of the comparison operator. (Hi) Order by clause is not used in subqueiy, since subqueries cannot manipulate the results internally.
Eg: We use subquery in an SELECT statement
SELECT * FROM employee WHERE EMPID IN (SELECT EMPID
FROM employee WHERE salary < 40000);
First, the inner query is executed, then the external or outer query is executed.
similarly the subqueries are used with INSERT, UPDATE and DELETE commands.

Choose the correct answer:

Question 1.
Which systems were known as predecessor of database system?
(a) Management
(b) file
(c) create
(d) update
Answer:
(b) file

Question 2.
What is called, same data is used by multiple resources for processing, thus created multiple copies of same data?
(a) Data Duplication
(b) Maintenance
(c) Security
(d) Management
Answer:
(a) Data Duplication

Question 3.
ACID Stands for:
(a) Atomicity, Consistency, Isolation, Durability
(b) Accessing, Consistency, Isolation, Durability
(c) Atomicity, Concurrency, Isolation, Differently
(d) Accessing, Consistency, Isolation, Differently
Answer:
(a) Atomicity, Consistency, Isolation, Durability

Question 4.
When multiple users do the transact! ons by accessing same object at the same time, the transaction is known as:
(a) Atomicity
(b) Consistency
(c) Concurrent
(d) Isolation
Answer:
(c) Concurrent

Question 5.
IMS stands for:
(a) International Machine Service
(b) Information Management System
(c) International Management System
(d) Information Management Service
Answer:
(b) Information Management System

Question 6.
IDS Stands for:
(a) Integrated Data save
(b) International Data store
(c) Integrated Data store
(d) Information Data store
Answer:
(c) Integrated Data store

Question 7.
Which schema defines all about the structure of the database?
(a) Network schema
(b) Sub schema
(c) Language
(d) Instance
Answer:
(a) Network schema

Question 8.
Which schema controls on views of the database for the user?
(a) Network schema
(b) Sub schema
(c) Language
(d) Instance
Answer:
(b) Sub schema

Question 9.
Which is basic procedural for accessing the database?
(a) Network schema
(b) Sub schema
(c) Language
(d) Instance
Answer:
(c) Language

Question 10.
What is called a table consisting of rows and columns?
(a) Network schema
(b) Sub schema
(c) Language
(d) Instance
Answer:
(d) Instance

Question 11.
Which is specifies the structure including name and type of each column?
(a) Language
(b) Instance
(c) Schema
(d) relation
Answer:
(c) Schema

Question 12.
A relation also known as:
(a) table
(b) columns
(c) rows
(d) files
Answer:
(a) table

Question 13.
A attribute also called as:
(a) table
(b) columns
(c) rows
(d) files
Answer:
(b) columns

Question 14.
A tuples also called as:
(a) table
(b) columns
(c) rows
(d) files
Answer:
(c) rows

Question 15.
OOP stands for:
(a) Object Oriented Programming
(b) Oracle Oriented Programming
(c) Objective Oriented Programming
(d) Obstacle Oriented Programming
Answer:
(a) Object Oriented Programming

Question 16.
Which software known as object oriented model uses small and reusable?
(a) Object
(b) Entity
(c) Attributes
(d) Relationship
Answer:
(a) Object

Question 17.
Which is used the most popular relational database?
(a) MSSQL
(b) MySQL
(c) Oracle
(d) MS Access
Answer:
(b) MySQL

Question 18.
Which is defined as the collection of data organized in terms of rows and columns?
(a) Rows
(b) Column
(c) Table
(d) File
Answer:
(c) Table

Question 19.
Which is defined in a table to hold values of same type?
(a) Row
(b) Column
(c) Table
(d) Attribute
Answer:
(d) Attribute

Question 20.
The vertical entity in a table is known as attribute or:
(a) Model
(b) Row
(c) Column
(d) compound
Answer:
(c) Column

Question 21.
A single entry in a table is called as row or record or:
(a) Tuple
(b) Model
(c) Compound
(d) Field
Answer:
(a) Tuple

Question 22.
Set of related data’s are represented in a row or:
(a) Column
(b) Tuple
(c) Field
(d) (a) and (b)
Answer:
(b) Tuple

Question 23.
The horizontal entity in a table is known as Record or:
(a) Column
(b) Row
(c) Field
(d) (a) and (b)
Answer:
(b) Row

Question 24.
Which type of key is perform the identification task?
(a) Primary key
(b) Super key
(c) Composite key
(d) Compound key
Answer:
(a) Primary key

Question 25.
Every tuple must have, by definition, a unique value for its:
(a) primary key
(b) super key
(c) composition key
(d) compound key
Answer:
(a) primary key

Question 26.
A primary key which is a combination of more than one attribute is called a:
(a) primary key
(b) foreign Key
(c) composite primary key
(d) super key
Answer:
(c) composite primary key

Question 27.
A foreign key is a copy of a:
(a) primary key
(b) foreign key
(c) composite primary key
(d) super key
Answer:
(a) primary key

Question 28.
Foreign keys can also be:
(a) zero
(b) null
(c) one
(d) negative
Answer:
(b) null

Question 29.
An attribute or group of attributes, which is sufficient to distinguish every • tuple in the relation from every other one is known as:
(a) primary key
(b) secondary key
(c) super key
(d) foreign key
Answer:
(c) super key

Question 30.
A key with more than one attribute to identify rows in a table is called:
(a) primary key
(b) secondary key
(c) super key
(d) composite key
Answer:
(d) composite key

Question 31.
Composite key is also known as:
(a) primary key
(b) super key
(c) composite key
(d) compound key
Answer:
(d) compound key

Question 32.
An _________ can be anything a real-world object or animation.
(a) object
(b) entity
(c) attribute
(d) isolate
Answer:
(b) entity

Question 33.
Which wilt always have a single value, that value can be a number or character or string?
(a) object
(b) entity
(c) attribute
(d) isolate
Answer:
(c) attribute

Question 34.
A person can hold n number of degrees” – Say which type of Attribute?
(a) Key Attribute
(b) Simple Attribute
(c) Composite Attribute
(d) Multi valued Attribute
Answer:
(d) Multi valued Attribute

Question 35.
Which is defined as the number of items that must be included in a relationship?
(a) Cardinality
(b) Entity
(c) Key
(b) Simple
Answer:
(a) Cardinality

Question 36.
Which database is founded by Monty Widenius and is named after his daughter name?
(a) MS Access
(b) SQL
(c) MySQL
(d) Oracle
Answer:
(c) MySQL

Question 37.
Which of the following is not a database?
(a) MySQL
(b) SQL
(c) Oracle
(d) Foxpro
Answer:
(b) SQL

Question 38.
Which of the following is open source database software?
(a) MySQL
(b) Oracle
(c) Foxpro
(d) MS Access
Answer:
(a) MySQL

Question 39.
In the MySQL database, there exists a table named:
(a) key
(b) host
(c) user
(d) password
Answer:
(c) user

Question 40.
Which command is similar to rebooting the server in MySQL?
(a) Flush privileges;
(b) select_priv;
(c) Insert_priv;
(d) Update_priv;
Answer:
(a) Flush privileges;

Question 41.
Which one of the following is most popular for web Administration?
(a) MySQL
(b) Work bench
(c) HeidiSQL
(d) PhPMYAdmin
Answer:
(d) PhPMYAdmin

Question 42.
Which database tool used by developers and DBA’s mainly for visualization?
(a) PhPMYAdmin
(b) MYSQL Workbench
(c) HeidiSQL
(d) MySQL
Answer:
(b) MYSQL Workbench

Question 43.
Which is open source tools helps in the administration of better database systems and GUI supports?
(a) PhPMYAdmin
(b) MYSQL Workbench
(c) HeidiSQL
(d) MySQL
Answer:
(c) HeidiSQL

Question 44.
How many major parts are needed that form a database?
(a) 2
(b) 3
(c) 4
(d) 5
Answer:
(b) 3

Question 45.
Which is a similar to an excel sheet containing multiple rows and columns?
(a) Rows
(b) Records
(c) Fields
(d) Tables
Answer:
(d) Tables

Question 46.
Which is standard Language used for accessing and manipulating databases?
(a) SQL
(b) Foxpro
(c) MS Access
(d) Oracle
Answer:
(a) SQL

Question 47.
Which SQL command are used to define database schema?
(a) DDL
(b)DML
(c)DQL
(d) DCL
Answer:
(a) DDL

Question 48.
Which SQL command deals with the manipulation of data present in the data base?
(a) DDL
(b) DML
(c) DQL
(d) DCL
Answer:
(b) DML

Question 49.
Which of the following command is data query language?
(a) INSERT
(b) UPDATE
(c) DELETE
(d) SELECT
Answer:
(d) SELECT

Question 50.
Which commands are manage the transactions in SQL databases?
(a) DDL
(b) DML
(c) TCL
(d) DCL
Answer:
(c) TCL

Question 51.
Which commands are that implement security on database objects?
(a) DDL
(b) DML
(c) TCL
(d) DCL
Answer:
(d) DCL

Question 52.
Which command is used to create new SQL database?
(a) New
(b) Select
(c) Create
(d) Insert
Answer:
(c) Create

Question 53.
Which command is used to remove any of the existing SQL Database?
(a) remove
(b) delete
(c) erase
(d) drop
Answer:
(d) drop

Question 54.
Which command is used to select suitable database for accessing?
(a) Open
(b) Use
(c) Select
(d) New
Answer:
(b) Use

Question 55.
Which command is used to add new row to the table?
(a) Add
(b) Update
(c) Insert
(d) New
Answer:
(c) Insert

Question 56.
Which command is used to remove an existing record in a table?
(a) Remove
(b) Delete
(c) Erase
(d) Drop
Answer:
(b) Delete

Question 57.
Which condition is specified to delete entire column data?
(a) INTO
(b) FROM
(c) ORDERBY
(d) WHERE
Answer:
(d) WHERE

Question 58.
Which command is used to modifying and updating the existing record in a table?
(a) Add
(b) Update
(c) Insert
(d) Modify
Answer:
(b) Update

Question 59.
Which command is used to sort the record in a table?
(a) WHERE
(b) MODIFY
(c) INTO
(d) ORDER BY
Answer:
(d) ORDER BY

Question 60.
Which clause is used to select data from more than two tables?
(a) FROM
(b) INTO
(c) JOIN
(d) COMBINE
Answer:
(c) JOIN

Question 61.
Sub queries are always written within the:
(a) file
(b) record
(c) field
(d) Parantheses
Answer:
(d) Parantheses

Question 62.
Which clause is not used in sub query?
(a) WHERE
(b) ORDER BY
(c) SELECT
(d) INSERT
Answer:
(b) ORDER BY

Question 63.
Match the following:

(a) (A) – (iii); (B) – (iv); (C) – (i); (D) – (ii)
(b) (A) – (iii); (B) – (i); (C) – (ii); (D) – (iv)
(c) (A) – (ii); (B) – (iv); (C) – (i); (D) – (iii)
(d) (A) – (ii); (B) – (i); (C) – (iii); (D) – (iv)
Answer:
(a) (A) – (iii); (B) – (iv); (C) – (i); (D) – (ii)

Question 64.
ODBMS Stands for:
(a) Objective Data Base Management System
(b) Object Data Base Management System
(c) Observe Data Base Management System
(d) Obstacle Data Base Management System
Answer:
(b) Object Data Base Management System

Question 65.
Which is called process of copying table contents into a file for future use? .
(a) Backup
(b) Save
(c) Store
(d) Copy
Answer:
(a) Backup

Question 66.
Match the following.

(a) (A) – (iii); (B) -;(ii); (C) – (i); (D) – (iv)
(b) (A) – (iv); (B) – (iii); (C) – (ii); (D) – (i)
(c) (A) – (iii); (B) – (i); (C) – (iv); (D) – (ii)
(d) (A) – (iv); (B) – (ii); (C) – (iii)- (D) – (i)
Answer:
(b) (A) – (iv); (B) – (iii); (C) – (ii); (D) – (i)

Question 67.
Match the following.

(a) (A) – (ii); (B) – (i); (C) – (iv); (D) – (iii)
(b) (A) – (ii); (B) – (iii); (C) – (iv); (D) – (i)
(c) (A) – (iii); (B) – (i); (C) – (iv); (D) – (ii)
(d) (A) – (iv); (B) – (i); (C) – (ii); (D) – (iii)
Answer:
(a) (A) – (ii); (B) – (i); (C) – (iv); (D) – (iii)

Question 68.
Match the following.

(a) (A) – (iii); (B) – (ii); (C) – (iv); (D) – (i)
(b) (A) – (ii); (B) – (iv); (C) – (i); (D) – (iii)
(c) (A) – (ii); (B) – (i); (C) – (iii); (D) – (iv)
(d) (A) – (iii); (B) – (i); (C) – (iv); (D) – (ii)
Answer:
(d) (A) – (iii); (B) – (i); (C) – (iv); (D) – (ii)

Question 69.
Match the following:

(a) (A) – (ii); (B) – (iii); (C) – (i); (D) – (iv)
(b) (A) – (ii); (B) – (i); (C) – (iv); (D) – (iii)
(c) (A) – (iv); (B) – (iii); (C) – (ii); (D) – (i)
(d) (A) – (iv); (B) – (i); (C) – (iii); (D) – (ii)
Answer:
(c) (A) – (iv); (B) – (iii); (C) – (ii); (D) – (i)

Question 70.
Match the following:

(a) (A) – (iii); (B) – (i); (C) – (iv); (D) – (ii)
(b) (A) – (iii); (B) – (ii); (C) – (iv); (D) – (i)
(c) (A) – (ii); (B) – (iv); (C) – (i); (D) – (iii)
(d) (A) – (ii); (B) – (i); (C) – (iii); (D) – (iv)
Answer:
(a) (A) – (iii); (B) – (i); (C) – (iv); (D) – (ii)

Question 71.

Choose the incorrect pair:
(a) Table – Excel sheet
(b) Queries – Views
(c) MySQL – Desktop App Tool
(d) CSV – Operating system
Answer:
(d) CSV – Operating system

Question 72.
Choose the incorrect pair:
(a) Alter -. Modify
(b) Drop – Delete a Table
(c) Truncate – Delete all Table
(d) Delete – Delete a database
Answer:
(d) Delete – Delete a database

Question 73.
Choose the incorrect pair:
(a) INSERT – Add new rows
(b) UPDATE – Rename
(c) SELECT – Retrieve
(d) ROLLBACK – Restore
Answer:
(b) UPDATE – Rename

Question 74.
Choose the incorrect pair:
(a) COMMIT – Permanent Save
(b) ROLLBACK – Restore database
(c) SAVE POINT – Save Temporarily
(d) SETTRANSACTION – Save in Hard disk
Answer:
(d) SETTRANSACTION – Save in Hard disk

Question 75.
Choose the incorrect pair:
(a) JOIN – Update
(b) Grant – Give permission
(c) Revoke – Out permission
(d) Drop – Remove
Answer:
(a) JOIN – Update

Question 76.
Choose the correct pair:
(a) WHERE – Query
(b) ORDER BY – Sorting
(c) GROUP BY – File
(d) SELECT – Database
Answer:
(b) ORDER BY – Sorting

Question 77.
Choose the correct pair:
(a) MySQL – Compiler
(b) Oracle – Operating system
(c) MS Access – RDBMS
(d) SQL – Objects
Answer:
(c) MS Access – RDBMS

Question 78.
Choose the correct pair:
(a) Atomicity – Changes
(b) Consistency – thumb rule
(c) Isolation – Concurrent
(d) Durability – Transaction
Answer:
(c) Isolation – Concurrent

Question 79.
Choose the correct pair:
(a) Table – Tuple
(b) Row – Record
(c) Column – Data
(d) Attribute – Row
Answer:
(b) Row – Record

Question 80.
Choose the correct pair.
(a) Primary Key – Rows –
(b) Secondary Key – Columns
(c) Foreign Key – Copy of Primary Key
(d) Composite Key – Super Key
Answer:
(c) Foreign Key – Copy of Primary Key

Question 81.
Choose the incorrect statement:
(a) The famous Hierarchical database model was IMS.
(b) Hierarchical database model each record has a tree structure.
(c) The collection of record was called fields.
(d) The individual records are equal to rows.
Answer:
(c) The collection of record was called fields.

Question 82.
Choose the incorrect statement:
(a) The first developed network data model was IDS.
(b) Network model is similar to relational model.
(c) The Network model are handled many to many relationship.
(d) The limitation of network model is difficulty in design and maintenance.
Answer:
(b) Network model is similar to relational model.

Question 83.
Choose the incorrect statement:
(a) The most popular relational database is Foxpro.
(b) MySQL is an open source database.
(c) MySQL supports different platforms like windows, Linux and MAC operating systems.
(d) The features of RDBMS are high availability and high performance.
Answer:
(a) The most popular relational database is Foxpro.

Question 84.
Choose the correct statement:
(a) A single entry in a table is called as column.
(b) The horizontal entity in a table is known as Record or Row.
(c) Each row is known as Attributes.
(d) The vertical entity in a table is known as Tuple.
Answer:
(b) The horizontal entity in a table is known as Record or Row.

Question 85.
Choose the correct statement:
(a) SQL is a Standard Query Language is a standard language used for accessing and manipulating databases.
(b) The CREATE command is used to draw a Animation. .
(c) DROP command is used to delete the record in a Table.
(d) TRUNCATE command is used to delete a structure of the Table.
Answer:
(a) SQL is a Standard Query Language is a standard language used for accessing and manipulating databases.

Question 86.
Assertion (A):
A Database Management System (DBMS) is system software for creating and managing databases.
Reason (R):
The DBMS provides users and programmers with a systematic way to create, retrieve, update and manage data.
(a) Both A and R are true, and R is the correct explanation for A.
(b) Both A and R are true, but R is not the correct explanation for A.
(c) A is true, But R is false.
(d) A is false, But R is true.
Answer:
(a) Both A and R are true, and R is the correct explanation for A.

Question 87.
Assertion (A):
The table consists of several files.
Reason (R):
Table can be divide into smaller parts, in terms of column.
(a) Both A and R are true, and R is the correct explanation for A.
(b) Both A and R are true, but R is not the correct explanation for A.
(c) A is true, But R is false.
(d) A is false, But R is true.
Answer:
(d) A is false, But R is true.

Question 88.
Assertion (A):
A foreign key is a copy of the whole of its parent primary key.
Reason (R):
Foreign key values have to be unique.
(a) Both A and R are true, and R is the correct explanation for A.
(b) Both A and R are true, but R is not the correct explanation for A.
(c) A is true, But R is false.
(d) A is false, But R is true.
Answer:
(c) A is true, But R is false.

Question 89.
Assertion (A):
An entity can be anything a real-world object or animation which is easily identifiable.
Reason (R):
Instances are the values for the entity.
(a) Both A and R are true, and R is the correct explanation for A.
(b) Both A and R are true, but R is not the correct explanation for A.
(c) A is true, But R is false.
(d) A is false, But R is true.
Answer:
(b) Both A and R are true, but R is not the correct explanation for A.

Question 90.
Assertion (A):
COMMIT is SQL TCL commands which is used to restore database to original form.
Reason (R):
ROLLBACK is SQL TCL commands which is used to permanent save.
(a) Both A and R are true.
(b) Both A and R are false.
(c) A is true, But R is false.
(d) A is false, But R is true.
Answer:
(b) Both A and R are false.

Question 91.
Pick the odd one out:
(a) SQL
(b) MySQL
(c) Oracle
(d) DBMS
Answer:
(d) DBMS

Question 92.
Pick the odd one out:
(a) Windows
(b) MS SQL
(c) Linux
(d) MAC
Answer:
(b) MS SQL

Question 93.
Pick the odd one out:
(a) INSERT
(b) SELECT
(c) DROP
(d) UPDATE
Answer:
(c) DROP

Question 94.
Pick the odd one out:
(a) ALTER
(b) PhPMyAdmin
(c) MySQLworkbench
(d) HeidiSQL
Answer:
(a) ALTER

Question 95.
Pick the odd one out:
(a) DROP
(b) TRUNCATE
(c) DELETE
(d) GRANT
Answer:
(d) GRANT

Question 96.
Pick the odd one out:
(a) ,(comma)
(b) ;(semicolon)
(c) :(colon)
(d) .(full stop)
Answer:
(b) ;(semicolon)

Question 97.
Which language is used to request information from a Database?
(a) Relational
(b) Structural
(c) Query
(d) Compiler
Answer:
(c) Query

Question 98.
The diagram gives a logical structure of the database graphically?
(a) Entity-Relationship
(b) Entity
(c) Architectural Representation
(d) Database
Answer:
(a) Entity-Relationship

Question 99.
An entity set that does not have enough attributes to form primary key is known as:
(a) Strong entity set
(b) Weak entity set
(c) Identity set
(d) Owner set
Answer:
(b) Weak entity set

Question 100.
Command is used to delete a database.
(a) Delete database databasename
(b) Delete databasename
(c) Drop database database name
(d) Drop database name
Answer:
(d) Drop database name

Question 101.
Which type of below DBMS is MySQL?
(a) Object Oriented
(b) Hierarchical
(c) Relational
(d) Network
Answer:
(c) Relational

Question 102.
MySQL is freely available and is open source.
(a) True
(b) False
Answer:
(a) True

Question 103.
represents a “tuple” in a relational database?
(a) Table
(b) Row
(c) Column
(d) Object
Answer:
(b) Row

Question 104.
Communication is established with MySQL using:
(a) SQL
(b) Network calls
(c) Java
(d) API’s
Answer:
(a) SQL

Question 105.
Which is the MySQL instance responsible for data processing?
(a) MySQL Client
(b) MySQL Server
(c) SQL
(d) Server Daemon Program
Answer:
(b) MySQL Server

Question 106.
The structure representing the organizational view of entire database is known as …………. in MySQL database.
(a) Schema
(b) View
(c) Instance
(d) Table
Answer:
(a) Schema

TN Board 12th Computer Applications Important Questions