SQLite
SQLite Create, Alter, Drop Table with Examples
In this article, we will see how to create tables, modify tables and dropping tables in SQLite3...
Before we learn Database Management System (DBMS) Software, let's understand-
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.
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 tutorial, you will learn more about-
| 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 |
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. |
Here, is the list of some popular DBMS system:
| 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. |
Four Types of DBMS systems are:
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 defines a database as a collection of objects which stores both data members values and operations.
DBMS may offer plenty of advantages but, it has certain flaws-
Although, DBMS system is useful. It is still not suited for specific task mentioned below:
Not recommended when you do not have the budget or the expertise to operate a DBMS. In such cases, Excel/CSV/Flat Files could do just fine.
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