A database is an organized collection of structured information, or data, typically stored and accessed electronically from a computer system.
Why do we need a database ?
- Database can store large amount of information and store it compactly (like handling over ten million users interacting on a site login credentials)
- They provide tools for easy assertion, query, updating of data
- They also offer security features and control over access of the data
- They generally scale well and better than using a file to store data
With databases there are two main categories
- SQL (SQL- Structured query language)
- NOSQL DATABASE
USE CASES
Databases are used to support internal operations of organizations and to underpin online interactions with customers and suppliers.
Databases are used to hold administrative information and more specialized data, such as engineering data or economic models. Examples include computerized library systems, flight reservation systems, computerized parts inventory systems, and many content management systems that store websites as collections of webpages in a database.
CLASSIFICATION OF DATABASES
We can classify database base on the type of their contents, for example: bibliographical, document-text, statistical, or multimedia objects. Another way is by their application area, for example: accounting, music compositions, movies, banking, manufacturing, or insurance. Or by looking at some technical aspect, such as the database structure or interface type.
1. An in-memory database
An in-memory database is a database that primarily resides in main memory, It is contrasted with database management systems that employ a disk storage mechanism ( backed-up by non-volatile computer data storage) . Main memory databases are faster than disk databases, and so are often used where response time is critical, such as in telecommunications network equipment.
2. A cloud database
A cloud database relies on cloud technology. Both the database and most of its DBMS reside remotely, "in the cloud", while its applications are both developed by programmers and later maintained and used by end-users through a web browser and Open APIs.
3. An active database
An active database includes an event-driven architecture which can respond to conditions both inside and outside the database. Possible uses include security monitoring, alerting, statistics gathering and authorization.
4. A document-oriented database
A document-oriented database is designed for storing, retrieving, and managing document-oriented, or semi structured, information. Document-oriented databases are one of the main categories of NoSQL databases.
5. A mobile database
A mobile database can be carried on or synchronized from a mobile computing device.
A database is usually controlled by a database management system (DBMS).
Database management system (DBMS) is the software that interacts with end users, applications, and the database itself allowing users to create, read, update, and delete data in the database.
DBMS manage the data, the database engine, and the database schema, allowing for data to be manipulated or extracted by users and other programs. This helps provide data security, data integrity, concurrency, and uniform data administration procedures.
Database management systems can be classified based on a variety of criteria such as the data model, the database distribution, or user numbers. The most widely used types of DBMS software are relational, distributed, hierarchical, object-oriented, and network.
1. Distributed database management system
A distributed DBMS is a set of logically interrelated databases distributed over a network that is managed by a centralized database application. This type of DBMS synchronizes data periodically and ensures that any change to data is universally updated in the database.
2. Hierarchical database management system
Hierarchical databases organize model data in a tree-like structure. Data storage is either a top-down or bottom-up format and is represented using a parent-child relationship.
3. Network database management system
The network database model addresses the need for more complex relationships by allowing each child to have multiple parents. Entities are organized in a graph that can be accessed through several paths.
4. Relational database management system
Relational database management systems (RDBMS) are the most popular data model because of its user-friendly interface. It is based on normalizing data in the rows and columns of the tables. This is a viable option when you need a data storage system that is scalable, flexible, and able to manage lots of information.
5. Object-oriented database management system
Object-oriented models store data in objects instead of rows and columns. It is based on object-oriented programming (OOP) that allows objects to have members such as fields, properties, and methods.
There is a wide range of database software solutions, including enterprise and open-source softwares and solutions available for database management.
Examples of DBMS
There is a wide range of database software solutions, including both enterprise and open source solutions, available for database management. Here are some of the most popular database management systems:
Oracle
Oracle database is a commercial relational database management system. It utilizes enterprise-scale database technology with a robust set of features right out of the box. Oracle Database is the first database designed for enterprise grid computing, the most flexible and cost effective way to manage information and applications. It can be stored in the cloud or on-premises.
MySQL
Mysql is an open-source general purpose relational database management system, originally written by Michael "Monty" Widenius and David Axmark.
It is commonly used with open-source content management systems and large platforms like Facebook, Twitter, and Youtube.
SQL Server
Developed by Microsoft, SQL Server is a relational database management system built on top of structured query language (SQL), a standardized programming language that allows database administrators to manage databases and query data.
SUMMARY
Now you should have a general understanding about databases and how they're used. Databases are not like most other files and require a little bit of thought in order for you to understand the concept.
If you have database management system installed, you should have a better understanding of where to start and how to choose from the various options to know how it works.