Content What is Data What is Database??? DBMS Uses ER-Diagram Purpose of Dbms Dbms Architecture Advantages Disadvantages

What is data

 Database is an organized collection of data. The data is typically organized to model aspects of reality in a way that supports processes requiring information. For example, modeling the availability of rooms in hotels in a way that supports finding a hotel with vacancies.

What is Database???A database is an organized collection of data. The data is typically organized to model aspects of reality in a way that supports processes requiring information. For example, modeling the availability of rooms in hotels in a way that supports finding a hotel with vacancies.

Database Management System

• A database management system (DBMS) is a collection of programs that enables you to store, modify, and extract information from a database. There are many different types of DBMSs, ranging from small systems that run on personal computers to huge systems that run on mainframes.

• The following are examples of database applications:

• Computerized library systems • Automated teller machines • Flight reservation systems • Computerized parts inventory systems

ENTITY RELATIONSHIP DIAGRAM

• The most important consideration is designing the database is how the information will be used. The various application and procedures that will be used in the database introduce the requirements upon the structure of data.

• In relational database, representation of data and data relationship is a collection of tables.

• Each table has one or more columns.

• The first step in creating a database is designing it. First plan is what are the tables that we require and the type of data it will contain. It also determines how the tables are related. That is a very important step and deserves careful consideration.

• It should determine the things we want to store as information and how are they related. A useful technique in designing the database is to draw a diagram of the tables. This graphical display of database is called an Entity Relationship Diagram (E.R Diagram).

. Each table has one or more columns.

The first step in creating a database is designing it. First plan is what are the tables that we require and the type of data it will contain. It also determines how the tables are related. That is a very important step and deserves careful consideration.

It should determine the things we want to store as information and how are they related.

A useful technique in designing the database is to draw a diagram of the tables. This graphical display of database is called an Entity Relationship Diagram (E.R Diagram).

SOME EXAMPLE OF DBMS ON FRONTEND

Advantages of Dbms

One of the main advantages of using a database system is that the

organization can exert, via

the DBA, centralized

management and control

over the data. The database

administrator is the focus of the centralized control.

• Reduction of Redundancies: Centralized control of data by the DBA avoids unnecessary duplication of data and effectively reduces the total amount of data storage required. It also eliminates the extra processing necessary to trace the required data in a large mass of data.

Elimination of Inconsistencies: Any redundancies that exist in the DBMS are controlled and the system ensures that these multiple copies are consistent.

Security: Data is of vital importance to an organization and may be confidential. Such confidential data must not be accessed by unauthorized persons.

Cost of software/hardware and migration: A significant disadvantage of the DBMS system is cost. In addition to the cost of purchasing or developing the software, the hardware has to be upgraded to allow for the extensive programs and work spaces required for their execution and storage.

Problem associated with centralization: While centralization reduces duplication, the lack of duplication requires that the database be adequately

backed up so that in the case of failure the data can be recovered. Centralization also means that the data is accessible from a single source. This increases the potential severity of security breaches and disruption of the operation of the organization because of downtimes and failures.