Database Overview

Database (DB)

A database is a structured collection of data that is organized and stored in a way that allows for efficient retrieval, management, and manipulation of the data.

Database Management System (DBMS)

A Database Management System (DBMS) is a software that provides an interface for managing databases, either with direct user actions via its CLI/GUI, or with standardized interface used by other parts of the application.

Core functionalities of DBMS include ensuring data integrity, security, and concurrency control.

Relational Database

A relational database is a type of database that organizes data into tables, consisting of rows and columns. Structured Query Language (SQL) is used for querying and manipulating data.

It follows the relational model, which defines relationships between tables using keys.

Non-Relational Database

A non-relational database, also known as NoSQL (Not Only SQL) provides flexible schema.

Data is arranged in various formats, such as key-value pairs, documents, graphs, or wide-column stores. Non-relational databases are designed to handle large amounts of unstructured or semi-structured data efficiently.

In Case You Are Wondering...

Each RDBMS speaks a different SQL.

They are just dialects of SQL with slightly different syntax and extensions. They all adhere to the ANSI SQL standard (commonly referred but not accurate) so that under most cases, same SQL statements can be used across all RDBMS without too much modification.

Non-relational DBMS are typically very different in the way they are store data, as you see from the above examples. Hence, there isn’t a standard for NoSQL.