Databases

A databse is an organized collection of structured information or data.
It is designed to allow data to be easily accessed, managed, modified, and retrieved, serving as the digital backbone for websites, mobile apps, and enterprise platforms.

• Accessed by multiple people simultaneously
• Store massive amounts of data
• Perform complex tasks while accessing data

At the core of every database is a Database Management System (DBMS). This software layer acts as the intermediary between the database, the end-users, and the applications, handling queries, updates, and access permissions without users needing to know the physical details of where the data resides.

Different Types of Databases#

Relational (SQL) database#

Store data in defined tables with rows and columns, linked together by unique identifiers. They excel at highly structured data and complex queries (e.g., Oracle Database, PostgreSQL, MySQL).

• It is a structured database containing tables that are related to each other.
• Each table contains fields of information. These are the columns of the tables.
• In addition, tables contain rows also called records. Rows are filled with specific data related to the columns in the table.
• Relational databases often have multiple tables.
• We can connect two tables if they share a common column. The columns that relate two tables to each other are called keys.

There are two types of keys.

• The first is called a primary key. The primary key refers to a column where every row has a unique entry. The primary key must not have any duplicate values, or any null or empty values. The primary key allows us to uniquely identify every row in our table.
• The second type of key is a foreign key. The foreign key is a column in a table that is a primary key in another table. Foreign keys, unlike primary keys, can have empty values and duplicates. The foreign key allows us to connect two tables together.

Non-Relational (NoSQL) Databases:#

Store data in various formats like key-value pairs, documents, or graphs. They are highly scalable and suited for unstructured or rapidly changing data (e.g., MongoDB, Redis).

Vector Databases#

Designed specifically to store data as vector embeddings, which are commonly used in generative AI and machine learning applications.