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What is DBMS ?

  • DBMS is represented by the DataBase Management System. A database management system (DBMS) is a software that allows creation, definition and manipulation of database, allowing users to store, process and analyze data easily.
  • DBMS provide us with an interface or a tool, to perform various operations like creating database, storing data in it, updating data, creating tables in the database and a lot more.
  • DBMS also provides protection and security to the databases.
  • It also maintains data consistency in case of multiple users.
  • Here are some examples of popular DBMS used these days:
    • MySQL
    • Oracle
    • SQL Server
    • IBM DB2
    • PostgreSQL
    • Amazon Simple DB (cloud based) etc.
What is DBMS

What is DBMS

Types of DBMS

  • Hierarchical Databse Model.
  • Network Databse Model.
  • Relational Databse Model.
  • Object-Oriented Databse Model.

Hierarchical Databse Model

  • In a Hierarchical database model, the 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 that are one to one or one to many.
  • In Hierarchical DBMS parent may have many children, but children have only one parent.
Hierarchical database Model

Hierarchical database Model

Network Database Model

  • The network database model allows each child to have multiple parents.
  • If you need to address the model help us to more complex relationships like as the orders/parts many-to-many relationship.
  • In this model, the entities are organized in a graph which can be accessed through several paths.
Network Database Model

Network Database Model

Relational Databse 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.
Relational Databse Model

Relational Databse Model

Object-Oriented Databse 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.
Object-Oriented Databse Model

Object-Oriented Databse Model

Advantages

  • Improved data sharing.
  • Improved data security.
  • Better data integration.
  • Minimized data inconsistency.
  • Improved data access.
  • Improved decision making.
  • Increased end-user productivity.

Disadvantages

  • Increased costs.
  • Management complexity.
  • Maintaining currency.
  • Frequent upgrade/replacement cycles.
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