Before the introduction to Database Management System (DBMS), let’s understand-
What is a Database?
A database is a collection of related data which represents some aspect of the real world. A database system is designed to be built and populated with data for a certain task.
What is DBMS?
Database Management System (DBMS) is a software for storing and retrieving users’ data while considering appropriate security measures. It consists of a group of programs which manipulate the database. The DBMS accepts the request for data from an application and instructs the operating system to provide the specific data. In large systems, a DBMS helps users and other third-party software to store and retrieve data.
DBMS allows users to create their own databases as per their requirement. The term “DBMS” includes the user of the database and other application programs. It provides an interface between the data and the software application.
In this Database Management System tutorial tutorial, you will learn DBMS concepts like-
What is a Database?
What is Database Management System (DBMS)?
Example of a DBMS
History of DBMS
Characteristics of Database Management System
DBMS vs. Flat File
Users in a DBMS environment
Popular DBMS Software
Application of DBMS
Types of DBMS
Advantages of DBMS
Disadvantage of DBMS
When not to use a DBMS system?
Example of a DBMS
Let us see a simple example of a university database. This database is maintaining information concerning students, courses, and grades in a university environment. The database is organized as five files:
- The STUDENT file stores data of each student
- The COURSE file stores contain data on each course.
- The SECTION stores the information about sections in a particular course.
- The GRADE file stores the grades which students receive in the various sections
- The TUTOR file contains information about each professor.
We need to specify the structure of the records of each file by defining the different types of data elements to be stored in each record.
We can also use a coding scheme to represent the values of a data item.
Basically, your Database will have 5 tables with a foreign key defined amongst the various tables.
History of DBMS
Here, are the important landmarks from the history:
- 1960 – Charles Bachman designed first DBMS system
- 1970 – Codd introduced IBM’S Information Management System (IMS)
- 1976- Peter Chen coined and defined the Entity-relationship model also know as the ER model
- 1980 – Relational Model becomes a widely accepted database component
- 1985- Object-oriented DBMS develops.
- 1990s- Incorporation of object-orientation in relational DBMS.
- 1991- Microsoft ships MS access, a personal DBMS and that displaces all other personal DBMS products.
- 1995: First Internet database applications
- 1997: XML applied to database processing. Many vendors begin to integrate XML into DBMS product
Characteristics of Database Management System
Here are the characteristics and properties of Database Management System:
- Provides security and removes redundancy
- Self-describing nature of a database system
- Insulation between programs and data abstraction
- Support of multiple views of the data
- Sharing of data and multiuser transaction processing
- Database Management Software allows entities and relations among them to form tables.
- It follows the ACID concept ( Atomicity, Consistency, Isolation, and Durability).
- DBMS supports multi-user environment that allows users to access and manipulate data in parallel.
DBMS vs. Flat File
DBMS Flat File Management System
Multi-user access It does not support multi-user access
Design to fulfill the need for small and large businesses It is only limited to smaller DBMS system.
Remove redundancy and Integrity Redundancy and Integrity issues
Expensive. But in the long term Total Cost of Ownership is cheap It’s cheaper
Easy to implement complicated transactions No support for complicated transactions
Users in a DBMS environment
Following, are the various category of users of a DBMS system
Component Name Task
Application Programmers The Application programmers write programs in various programming languages to interact with databases.
Database Administrators Database Admin is responsible for managing the entire DBMS system. He/She is called Database admin or DBA.
End-Users The end users are the people who interact with the database management system. They conduct various operations on database like retrieving, updating, deleting, etc.
Popular DBMS Software
Here, is the list of some popular DBMS system:
MySQL
Microsoft Access
Oracle
PostgreSQL
dBASE
FoxPro
SQLite
IBM DB2
LibreOffice Base
MariaDB
Microsoft SQL Server etc.
Application of DBMS
Below are the popular database system applications:
Sector Use of DBMS
Banking For customer information, account activities, payments, deposits, loans, etc.
Airlines For reservations and schedule information.
Universities For student information, course registrations, colleges and grades.
Telecommunication It helps to keep call records, monthly bills, maintaining balances, etc.
Finance For storing information about stock, sales, and purchases of financial instruments like stocks and bonds.
Sales Use for storing customer, product & sales information.
Manufacturing It is used for the management of supply chain and for tracking production of items. Inventories status in warehouses.
HR Management For information about employees, salaries, payroll, deduction, generation of paychecks, etc.
Types of DBMS
Types of DBMS
Tha main Four Types of Database Management System are:
Hierarchical database
Network database
Relational database
Object-Oriented database
Hierarchical DBMS
In a Hierarchical database, model data is organized in a tree-like structure. Data is Stored Hierarchically (top down or bottom up) 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 like as the orders/parts many-to-many relationship. 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 is one of the components of DBMS that defines a database as a collection of objects which stores both data members values and operations.
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