What is Data Model?

Definition:

A data model is a description of the organization of data in a database. It also describes the relationship among data and any constraints that have to be defined on the data.

Data models can be broadly be classified into two categories:

• Object-based logical model

          It focuses on describing the data, the relationship among the data, and any constraints defined.

• Record-base logical model

          It focuses on describing the data structure and the access techniques in a Database Management System.

What is Database Management system (DBMS)?

Definition 1:

A database management system (DBMS) is a software used to store and manage data. A DBMS stores data in databases and uses data models to describe the various ways of organizing data.

Definition 2:

Database Management System  is the task of maintaining databases so that information is readily available.

DBMS's are designed to maintain large volumes of data.Management of data involves:

• Defining structures of data storage.
• Providing mechanisms for data manipulation such as adding, editing, and deleting data.
• Providing data security against unauthorized access.

What is a Database?

Definition:

A database is a collection of logically related information.


Following are the top 10 database engines using by companies around the globe:

• Oracle
• MySQL
• Microsoft SQL Server
• PostgreSQL
• DB2
• MongoDB
• Microsoft Access
• SQLite
• Sybase
• Teradata

What is Relational Database Management System (RDBMS)?

Definition:

A relational database management system (RDBMS) is an advanced version of DBMS that also defines the relationship between the various data values. It helps in organizing and accessing data more efficiently than DBMS.

What is a Class in Object Oriented Programming (OOP)?

Definition:

Class is a declaration, a template, or a blueprint that can be used to classify objects.

For example, the peacock, the sparrow, and the kingfisher are all birds. All of them share characteristics that are common to the family of birds. All of them lay eggs, are covered with feathers, have hollow bone structures, and have the ability to fly. Therefore, they share structural and behavioral similarities and belong to the class called Birds.

What is an object in Object Orientation (OOP)?

Definition 1:

An object is a combination of messages and data. Objects can receive and send messages and use messages to interact with each other. The messages contain information that is to be passed to the recipient object.


Definition 2:

An object literally means a 'material thing' that is capable of being presented to the senses.


Definition 3:

An object is a tangible entity that may exhibit some well-defined behavior. For example, let us consider a tennis ball:

• A tennis ball is a tangible entity, with a visible boundary.
• A tennis ball has a specific defined purpose (such as bouncing)
• You can direct a specific action towards a tennis ball by hitting it with racquet or by tossing it.

What is Object Oriented Programming (OOP) ?

Object-Oriented Programming (OOP) is one of the most popular methodologies in software development. It offers a powerful model for creating computer programs. It speeds the program development process, improves maintenance and enhances reusablity of programs.