What is a Database?

A Complete Guide. A database is a storage system that stores data in an organized manner for easy access and management. In just the last two years, 90% of the world’s data has been created, and the volume of global data doubles every two years. All this data is stored in databases.

In computing, a database is an organized collection of data or a type of data store based on the use of a database management system (DBMS), the software that interacts with end users, applications, and the database itself to capture and analyze the data. The DBMS additionally encompasses the core facilities provided to administer the database. The sum total of the database, the DBMS and the associated applications can be referred to as a database system. Often the term “database” is also used loosely to refer to any of the DBMS, the database system or an application associated with the database.

Small databases can be stored on a file system, while large databases are hosted on computer clusters or cloud storage. The design of databases spans formal techniques and practical considerations, including data modeling, efficient data representation and storage, query languages, security and privacy of sensitive data, and distributed computing issues, including supporting concurrent access and fault tolerance.

Introduction

Although they were first invented decades ago, computer-based databases have become ubiquitous on today’s internet. More and more commonly, websites and applications involve collecting, storing, and retrieving data from a database. For many years the database landscape was dominated by relational databases, which organize data in tables made up of rows. To break free from the rigid structure imposed by the relational model, though, a number of different database types have emerged in recent years.

These new database models are jointly referred to as NoSQL databases, as they usually do not use Structured Query Language — also known as SQL — which relational databases typically employ to manage and query data. NoSQL databases offer a high level of scalability as well as flexibility in terms of data structure. These features make NoSQL databases useful for handling large volumes of data and fast-paced, agile development.

This conceptual article outlines the key concepts related to document databases as well as the benefits of using them. Examples used in this article reference MongoDB, a widely-used document-oriented database, but most of the concepts highlighted here are applicable for most other document databases as well.

Database definition

A database is a structured collection of data designed to store, manage, and retrieve information. In a database, also denoted as DB, data is normally arranged within tables, defined by rows and columns, like a spreadsheet layout that facilitates data organization. The structure makes it easy to query data, which is mostly done using Structured Query Language (SQL)—the language used to interact with relational databases. You need a database management system (DBMS), or database software, to interact with a database and manage (access, modify, update, or delete) the data it contains.

These systems ensure you can interact with the database through a unified interface. Some examples of DBMS include:

• MongoDB
• Oracle Database
• PostgreSQL
• MySQL
• SQL Server

The functionality of databases extends to various operations, such as inserting new data, updating existing data, deleting old data, and querying data based on your specific criteria. For example, in a database containing customer information, you might want to retrieve data for all customers who live in a specific city. The criterion in this case would be “City equals New York.” This would result in a dataset of customers whose city field in the database matches “New York.” This type of data retrieval criteria is known as a “selection” operation and is a core function facilitated by SQL.

Major components of a database

Databases are the core of modern information management, but what are the elements that make a database a database? Here are the major components that define its structure:

Data

Data is the most important component of any database. It is the stored information that the systems within an organization interact with and manage. Data in a database is organized in a way that allows for easy access, manipulation, and analysis, supporting various business operations and decision-making processes.

Database engine

A database engine is the underlying software that enables the database to operate effectively and carry out its intended functions. Some examples of database engines include:

• MongoDB (for NoSQL databases)
• Amazon Aurora
• Google Cloud Spanner

Organizations also use embedded database engines and in-memory database engines to improve application performance.

Database schema

A database schema defines the structure and constraints of your database. In terms of relational databases, it specifies the tables, the fields within each table, and the relationships between them. It’s a model of how your data will look. The schema doesn’t contain any data itself; it just facilitates database design per your organization’s needs

Database access language

It refers to the language you can use to write queries and commands to interact with databases. SQL is the most prevalent language, but variants like MySQL and Presto also exist.

Query processor

As the name suggests, a query processor processes your database queries in executable form.

Metadata

Metadata serves as an instruction manual for your database, providing essential details about its contents and structure. Stored in data dictionaries, this “data about data” helps the database software understand how to interact with the information stored within.

Hardware components

Hardware components are the physical components of a system on which a database runs. These are required for storing data, executing software, and ensuring smooth operation of the database. The hardware components of a database include:

Storage devices: these are devices that hold all the data a database manages; these can be hard drives (HDDs) or solid-state drives (SSDs). The choice between HDDs and SSDs can affect the speed and efficiency of data retrieval.

Memory (RAM): It temporarily holds data that is actively being used or processed, making data retrieval operations quicker.

Processor (CPU): The central processing unit, CPU, performs the data processing operations, such as command execution, query processing, and transactions.

Network components: These are the communicators of the database. Network components include network cards and routers that connect the database server to the wider network, allowing it to send and receive data from other systems and users.

Types of databases

There are different types of databases. The right database for your organization will be the one that caters to its specific requirements, such as unstructured data management, accommodating large data volumes, fast data retrieval or better data relationship mapping. Here are some types of databases:

Types of Databases:

1. Data Warehouses
2. Document-oriented databases
3. Object-oriented databases
4. Disrtribed databases
5. Network Database
6. Hierarchical Databases 
7. SQL databases
8. NoSQL databases

To view the various database types, please click the link below.

👉 Types of Databases