KPK 11th Class Computer Chapter 7 Database Fundamentals Short Questions Answers
KPK 11th Class Computer Chapter 7 Database Fundamentals Short Questions with answers are combined for all 11th class(Intermediate/hssc) Level students.Here You can prepare all Computer Chapter 7 Database Fundamentals short question in unique way and also attempt quiz related to this chapter. Just Click on Short Question and below Answer automatically shown. After each question you can give like/dislike to tell other students how its useful for each.
Class/Subject: 11th Class Computer
Chapter Name: Database Fundamentals
Board: All KPK Boards
- Malakand Board 11th Class Computer Chapter 7 Database Fundamentals short questions Answer
- Mardan Board 11th Class Computer Chapter 7 Database Fundamentals short questions Answer
- Peshawar Board 11th Class Computer Chapter 7 Database Fundamentals short questions Answer
- Swat Board 11th Class Computer Chapter 7 Database Fundamentals short questions Answer
- Dera Ismail Khan Board 11th Class Computer Chapter 7 Database Fundamentals short questions Answer
- Kohat Board 11th Class Computer Chapter 7 Database Fundamentals short questions Answer
- Abbottabad Board 11th Class Computer Chapter 7 Database Fundamentals short questions Answer
- Bannu Board 11th Class Computer Chapter 7 Database Fundamentals short questions Answer
Helpful For:
- All KPK Boards 11th Class Computer Annual Examination
- Schools 11th Class Computer December Test
- KPK 11th Class Computer Test
- Entry Test questions related Computer
KPK 11th Class Computer Chapter 7 Database Fundamentals Short Questions Answers
Definition
Database is an organized collection of related data. The word organized means that data is stored in such a way that the user can store, manipulate and retrieve data easily. The word related means that a database is normally created to store the data about a particular topic.
1. Students names in a class are data while names of students in alphabetic order is an information.
- A days temperature, wind speed and humidity recoded are data while weather prediction as cold or warm is information.
- A students subject marks are data while his parentage of marks, grade and division are information.
- Data Redundancy: redundancy means duplication of data. Since same data is stored in multiple files which are needed by different application programs which causes data redundancy.
- Data Isolation: Isolation means separation of date i.e. related data is scattered in multiple files. It is different and time consuming to write at once.
- Poor Data Security: File management system does not provide adequate security on data. The data can be easily accessed and changed by unauthorized user. Applying security techniques such as password protection and locking of files is very difficult.
- Sharing of Data: The primary objective of the database approach is sharing of data. Authorized users can use the shared database according to their needs and right.
- Improved Data Security: Data security means protection of data from unauthorized users. The security is maintained by allowing access to the database through use of passwords.
- Backup and Recovery: It means to keep the same copy of the data in many places for safe side and it the data is lost due to any bad luck it may be recovered in emergency. DBMS provides facilities for backup and recovery from failures including disk crash, software errors etc.
- User-friendliness: Using DBMS, user can easily access and manipulate data in database. DBMS provides a user friendly interface for interaction with data base.
DDL | DML |
DDL is shot for Data Definition Language. It is a database language having statements which are used to define the database structure in which actual data is stored. | DML is short for Manipulation Language. It is a language that supports the basic data manipulation operations on data in databases. |
Examples of DDL statements are:
CREATE- to create objects in the database ALTER – change the structure of the database DROP – delete objects from the database RENAME- rename an object. |
Examples of Data manipulation operations are:
INSERT: Insertions of new data in database MODIFY: Modification of data in database RETRIEVE: Retrieval of data from database DELETE: Deletion of data from database. |
Data model is a logical representation of a real world situation about which data is to be collected and stored in a database. It is used to describe the elements of a database system and their relationships.
Cardinality | Modality | |
1 | Cardinality is the maximum number of times an instance in one entity can be associated with instances in the related entity. | Modality is the minimum number of times an instance in one entity can be associated with an instances in the related entity. |
2 | Cardinality can be 1 or Many and the symbol is placed on the outside ends of the relationship line, closest to the entity. | Modality can be 1 or 0 and the symbol is placed on the inside, next to the cardinality symbol. |
3 | For a cardinality of 1 a straight line drawn. | For a modality of a straight line is drawn. |
4 | For a cardinality of Many a foot with three toes is drawn. | For a modality of 0 a circle is drawn. |
A Primary Key is a column or group of columns that uniquely identify a row or record. Every table should have a primary key.
Primary Key must have the following characteristics.
- The value of a primary key must not be duplicated throughout the database.
- The value of a primary key must not be NULL anywhere in the database.
An Example of Primary Key is Roll No of entity STUDENT
Primary Key |
Roll No | First Name | Last Name | Coursed |
001 | Junaid | Khan | E002 |
127 | Arif | Shah | U05 |
287 | Wasim | Shahid | P08 |
389 | Ali | Khan | C12 |
896 | Ijaz | Aslam | M20 |
A Foreign Key is a column or set of columns in one table whose values must have matching values in the primary key of another (or the same) table.
A relation is the combination of columns and rows.Relations is the fundamental object of database. The basic purpose of a relation is to store data. A relation has specified number of columns and may have many numbers of rows. A relation cannot contain duplicate rows. Column
Roll No | First Name | Last Name | Coursed | |
001 | Junaid | Khan | E002 | |
127 | Arif | Shah | U05 | |
287 | Wasim | Shahid | P08 | |
Rows 389 | Ali | Khan | C12 | |
896 | Ijaz | Aslam | M20 |
A database administrator (DBA) is responsible for the development and design of database and improving database performance and capacity, and planning for future expansion requirements.
Role of database administrator:
- Installing and upgrading the database server
- Allocating system storage
- Enrolling users and maintaining system security
- Controlling and monitoring user access to the database
- Backing up and restoring databases