A.Kavitha,Assistant Professor

1. A.KAVITHA
ASSISTANT PROFESSOR
E.M.G YADAVA WOMEN’S COLLEGE,MADURAI

3. UNIT 1
INTRODUTION-DATABASE MANAGEMENT SYSTEM
WHY DATABSE
CHARACTERSTICS OF DATA IN DATABASE
DATABASE MANAGEMENT SYSTEM
TYPES
SOFTWARE DEVELOPMENT LIFE CYCLE(SDLC)
DATABASE DEVELOPMENT LIFE CYCLE(DDLC)

4. INTRODUCTION DBMS
• A database management system (DBMS) refers to the technology for creating and
managing databases. DBMS is a software tool to organize (create, retrieve, update,
and manage) data in a database.
• The main aim of a DBMS is to supply a way to store up and retrieve database
information that is both convenient and efficient.
Database
• The database is a collection of inter-related data which is used to retrieve, insert
and delete the data . It is also used to organize the data in the form of a table,
schema, views, and reports, etc.
Database Management System
• Database management system is a software which is used to manage the database.
• DBMS provides an interface to perform various operations like database creation, storing
data in it, updating data, creating a table in the database and a lot more.
• It provides protection and security to the database. In the case of multiple users, it also
maintains data consistency.

5. DBMS allows users the following tasks:
• Data Definition: It is used for creation, modification, and removal of definition that defines
the organization of data in the database.
• Data Updation: It is used for the insertion, modification, and deletion of the actual data in the
database.
• Data Retrieval: It is used to retrieve the data from the database which can be used by
applications for various purposes.
• User Administration: It is used for registering and monitoring users, maintain data integrity,
enforcing data security, dealing with concurrency control, monitoring performance and
recovering information corrupted by unexpected failure.

6. WHY DATABASE
• To develop software applications In less time.
• Data independence and efficient use of data.
• For uniform data administration.
• For data integrity and security.
• For concurrent access to data, and data recovery from crashes.
• To use user-friendly declarative query language.

7. CHARACTERISTICS OF DATA IN DATABASE
• It uses a digital repository established on a server to store and manage the
information.
• It can provide a clear and logical view of the process that manipulates data.
• DBMS contains automatic backup and recovery procedures.
• It contains ACID properties which maintain data in a healthy state in case of
failure.
• It can reduce the complex relationship between data.
• It is used to support manipulation and processing of data.
• It is used to provide security of data.
• It can view the database from different viewpoints according to the
requirements of the user.

8. ADVANTAGES OF DBMS
• Controls database redundancy: It can control data redundancy because it stores all the data
in one single database file and that recorded data is placed in the database.
• Data sharing: In DBMS, the authorized users of an organization can share the data among
multiple users.
• Easily Maintenance: It can be easily maintainable due to the centralized nature of the
database system.
• Reduce time: It reduces development time and maintenance need.
• Backup: It provides backup and recovery subsystems which create automatic backup of
data from hardware and software failures and restores the data if required.
• multiple user interface: It provides different types of user interfaces like graphical user
interfaces, application program interfaces

9. DISADVANTAGES OF DBMS
• Cost of Hardware and Software: It requires a high speed of data processor
and large memory size to run DBMS software.
• Size: It occupies a large space of disks and large memory to run them
efficiently.
• Complexity: Database system creates additional complexity and
requirements.
• Higher impact of failure: Failure is highly impacted the database because in
most of the organization, all the data stored in a single database and if the
database is damaged due to electric failure or database corruption then the
data may be lost forever.
•Complexity: Database system creates additional complexity and requirements.
•Higher impact of failure: Failure is highly impacted the database because in most of the organization, all the data stored in a single database and if the database is damaged due to electric failure or databas

10. TYPES OF DBMS

11. Four Types of DBMS systems are:
• Hierarchical database
• Network database
• Relational database
• Object-Oriented database

12. Hierarchical DBMS
• In a Hierarchical database, model data is organized in a tree-like structure. Data is Stored Hierarchically
format. Data is represented using a parent-child relationship. In Hierarchical DBMS parent may have
many children, but children have only one parent.
Network Model
• The network database model allows each child to have multiple parents. It helps you to address the
need to model more complex relationships . In this model, entities are organized in a graph which can
be accessed through several paths.
Relational model
• Relational DBMS is the most widely used DBMS model because it is one of the easiest. This model is
based on normalizing data in the rows and columns of the tables. Relational model stored in fixed
structures and manipulated using SQL.
Object-Oriented Model
In Object-oriented Model data stored in the form of objects. The structure which is called classes which
display data within it. It defines a database as a collection of objects which stores both data members
values and operations.

13. SOFTWARE DEVELOPMENT LIFE CYCLE(SDLC)
• The Systems Development Life Cycle (SDLC) is a process used in the development, creation,
and maintenance of an information system. This process is often used in the creation or
updating of a database system.
• SDLC is a process followed for a software project, within a software organization. It consists of
a detailed plan describing how to develop, maintain, replace and alter or enhance specific
software. The life cycle defines a methodology for improving the quality of software and the
overall development process.

15. Planning
During this phase, the group that is responsible for creating the system must first determine what the
system needs to do for the organization (requirements gathering).
• What do we need this system for ?
• What will the system do for the organization ?
• How are we going to make this system ?
Analysis
The Analysis Phase the second phase of the SDLC and is when the group that has been placed in
charge of the project must decide if the project should go ahead with the resources available. This
also includes looking at any existing system to see what it is doing for the organization and how well
that system is doing its job.
• Can this system be created with the resources (and budget) we have available?
• Will this system significantly improve the organization?
• Does the old system even need to be replaced?

16. Design
The Design stage is the third stage of the System development life cycle and it involves the actual creation
and design of a system. This is where they put together the different pieces that will create the system. In a
database approach, The server hosting the database
• The software that will form the database (Access, Oracle, mySQL, etc)
• Other needed DBMS (Database Management System) software
Implementation
The Implementation Phase is the final phase of the SDLC and it involves the actual construction and
installation of a system.
• Physical installation of the server hosting the database
• Installation of the database onto the system
• Installation of the Database Management System
• Initialization and continuous operation of the database and DBMS
• Maintaining the hardware and software hosting the database
• Updating the hardware (physical hard drives, etc) and software (DBMS) as needed
• Any future expansion of the database.

17. DATABASE DEVELOPMENT LIFE CYCLE(DDLC)
Database Development Life Cycle
The database development life cycle (DDLC) is a process of designing,
implementing and maintaining a database system to meet strategic or
operational information needs of an organisation or enterprise such as:
• Improved customer support and customer satisfaction.
• Better production management.
• Better inventory management.
• More accurate sales forecasting.
• The database development life cycle (DDLC) is inherently associated with
the software development life cycle (SDLC) of the information system.

18. THE TERM DATABASE DEVELOPMENT LIFECYCLE IS ONE THAT’S USED TO DESCRIBE THE FIVE MAJOR
STAGES THAT ARE PASSED THROUGH DURING THE DEVELOPMENT PROCESS.

19. Planning and Strategy
The very first, and arguably the most important, aspect of
database development is planning and strategy. This is essential for
determining the framework and requirements of the database being
developed.
Analysis
The analysis stage is an extension of planning and strategy, which
takes an even more in depth look at how data development should
be carried out. This typically involves a team looking at your data
development needs, the platform to be used, the timeline of the
project, and how cost factors into all of it.

20. Design Phase
This is the nuts and bolts phase of the life cycle. This is where the planning and analysis
are implanted and the database program is designed. There is usually a period of trial and
testing in this phase, so it’s common for developers to make a new database available to
clients on a very limited basis to assess its function and determine any modifications that
need to be made to the existing plan.
Implementation
Once a database has been developed, tested, and tweaked to optimize performance, it is
then made available for the client to use for everyday practical applications. Ideally, things will
run smoothly, but as is the case with all things technical, errors and maintenance are still
needed, which brings us to the next stage of the database development lifecycle.
Maintenance
A trusted, professional database developer isn’t going to consider their job done once the
database is up and running. They’ll be on hand to handle any needed updates or to address
any technical issues that may arise. In the event of a major issue with your database platform,
they’ll work to rebuild it and then move it through the trial and implementation stages of the
lifecycle once again.