best computer science ppt

1. 12TH CLASS
COMPUTER
SCIENCE
PROJECT WORK

2. DATABASE
MANAGEMENT
SYSTEM
DONE BY :
MADHULATHA.G

3. CERTIFICATE
THIS IS TO CERTIFY THAT MADHULATHA GOLLAPALLI OF CLASS 12TH A HAS
PREPARED THE PPT ON DATA BASE MANAGEMENT SYSTEM.THIS PPT IS THE
RESULT OF HER EFFORTS AND ENDEAVOURS. THE PPT IS FOUND WORTH OF
ACCEPTANCE AS FINAL PROJECT FOR THE SUBJECT COMPUTERSCIENCE OF
CLASS 12TH.
SIGNATURE OF GUIDED EXAMINER: SIGNATURE OF INTERNAL:
SIGNATURE OF PRINCIPAL:

4. ACKNOWLEDGEMENT
IT IS MY FOREMOST DUTY TO EXPRESS MY DEEP
REGARDS AND GRATITUDE TO MY COMPUTER
SCIENCE TEACHER MALIKAPARWIN MAM UNDER
WHOSE GUIDENCE AND SUPERVISION I WAS ABLE TO
COMPLETE THIS PRESENTATION.

5. CONTENTS:
 INTRODUCTION
 PURPOSE OF DBMS
 USE OF DBMS
 ADVANTAGES & LIMITATIONS
 COMPONENTS OF DBMS
 DATA ABSTRACTION
 WORKING OF DBMS
 DBMS VERSUS FILE PROCESSING SYSTEM
 DATA MODEL
 HIERARCHICAL DATA MODEL
 NETWORK DATA MODEL
 RELATIONAL DATA MODEL

6. INTRODUCTION
DATABASE MAY BE DEFINED AS A
COLLECATION OF INTERRELATED DATA
STORED TOGETHER TO SERVE MULTIPLE
APPLICATIONS DATABASE.

7. PURPOSE OF DBMS
DBMS PROVIDE A WAY TO STORE AND RETRIEVEDATABASE
INFORMATION THAT IS BOTH CONVENIENT AND EFFICIENT. DATA IN
THE DATABASE CAN BE ADDED, DELETED, CHANGED,SORTED OR
SEARCHED, ALL USING A DBMS.
APPLICATION PROGRAM ACCESSES THE DATA IN THE DATABASE BY
SENDING REQUEST TO THE DBMS.
EX:MYSQL,INGRES,MS-ACCESS etc…

9. THE BASIC PROCESSES THAT ARE SUPPORTED BY A DBMS ARE:
(i) Specification of data types, structures and constrains to be considered in an
application.
(ii) Storing the data itself into persistent storage.
(iii) Manipulation of database.
(iv) Querying the database to retrieve desired information.
(v) Updating the content of the database.

10. ADVANTAGES OF DBMS
(i) Reduced data
redundancy.
(ii) Elimination of
inconsistency.
(iii)Data sharing.
(iv)Data integrity.
(v) Data security.
(vi)Backup and recovery.
LIMITATIONS OF DBMS
(i) High cost.
(ii) Database failure.
(iii)Data quality.
(iv)Confidentiality, privacy
and security.

11. COMPONENTS OF DATABASE SYSTEM
 A database is composed of four components- User, Hardware, Software and Data, which coordinate with one another to form an effective database
system.
 USER: The users are the people who manage the database and perform different operations on it.
 HARDWARE: The hardware consists of various secondary storage devices, such as magnetic tapes, hard disks, floppy disks CD-ROM’s etc.
 SOFTWARE: This is the most important component of database. It acts as an interface between the user and the database.
 DATA: It is an important component of database. Most of the organisations generate, store and process large amount of data. The data acts as a
bridge between the hardware, software and the users.
USERDATA:It contains a table of data in the form of rows (records) and columns (fields)
METADATA: It means ‘data about data’ i.e. a logical description of the structure of a data
APPLICATIONDATA: It contains the structure and format queries, reports and other application components.

12. Data abstraction
 The major purpose of a database system is to provide users with an abstract view of
data. That is, the system hides certain details of how the data are stored and
maintained.
 Since many database system uses are not computer trained, developers hide the
complexity from users through several levels of abstraction, to simplify user’s
interactions with the system. this concept is known as data abstraction.

13. Working of database
 Databases are created to operate on large quantities of information by input, retrieve and manage the information.
 Database is a centralized location which provides an easy way to access the data by several users. It does not keep the
separate copies of a particular data file still a number of users can access the same data at the same time.
 As the below diagram shows to perform any operation in the presence of a DATABASE MANAGEMENT SYSTEM (DBMS).
USERS REQUEST DBMS DATABASE
RESPONSE

14. DBMS versus FILE PROCESSING SYSTEM
DBMS
 A database managementsystem co-ordinates both the
physical and logical access to the data.
 A database managementsystem is a bundle of applications,
i.e. dedicated for managing data stored in a database.
 A database managementsystem is designed to allow flexible
access to data (i.e. queries).
 A database managementsystem is designed to co-ordinate
multiple users accessing the same data at the same time.
FILE PROCESSING SYSTEM
 File processing system co-ordinates only the physical access.
 A file processing system is a collection of raw data files stored
in the hard drive of a system.
 File processing system is designed to allow predetermined
access to data (i.e. compiled programs).
 A file processing system is usually designed to allow one or
more programs to access different data files at the same time.

15. Data model
Data model can be defined as A Database model defines the logical design and structure
of a database and defines how data will be stored, accessed and updated in a database
management system. While the Relational Model is the most widely used database model,
there are other models too:
• Hierarchical Model
• Network Model
• Relational Model

16. Hierarchical data model
 This database model organises data into a tree-like-structure, with a single root, to which all the other data is
linked. The hierarchy starts from the Rootdata, and expands like a tree, adding child nodes to the parent
nodes.
 In this model, a child node will only have a single parent node.
 This model efficiently describes many real-world relationships like index of a book, recipes etc.
 In hierarchical model, data is organised into tree-like structure with one one-to-many relationship between two
different types of data, for example, one department can have many courses, many professors and of-course
many students.

17. Network model
This is an extension of the Hierarchical model. In this model data is organised more like a graph, and are allowed to have
more than one parent node.
In this database model data is more related as more relationships are established in this database model. Also, as the data is
more related, hence accessing the data is also easier and fast. This database model was used to map many-to-many data
relationships.
This was the most widely used database model, before Relational Model was introduced.
Network Model of database

18. Relational database model
 In this model, data is organised in two-dimensional tables and the relationship is maintained by storing a common
field.
 This model was introduced by E.F Cod in 1970, and since then it has been the most widely used database model,
infact, we can say the only database model used around the world.
 The basic structure of data in the relational model is tables. All the information related to a particular type is stored
in rows of that table.
 Hence, tables are also known as relationsin relational model.
 In the coming tutorials we will learn how to design tables, normalize them to reduce data redundancy and how to
use structured query language to access data from tables.

20. DECLARATION
I THE UNDERSIGNED SOLOMNLY DECLARE THAT THE PROJECT
REPORT “DATABASE MANAGEMENT SYSTEM” IS
BASED ON MY OWN WORK CARRIED OUT DURING THE COURSE OF
STUDY UNDER THE SUPERVISION OF MALIKA PARVEEN. I
ASSURE THE STATEMENTS MADE AND CONCLUSIONS DRAWN ARE
AN OUTCOME OF MY RESEARCH WORK. IS THE REPORT IS ORGINAL
AND HAS BEEN DONE BY UNDER THE GENERAL SUPERVISION OF MY
SUPERVISIOR.