TryHackMe — SQL Fundamentals | Cyber Security 101 (THM)

Databases 101

Introducing Databases
Databases are organized collections of data that are accessible and analyzable. They store various types of data, like user information for apps, user-generated content on social media, and watch history for streaming services. Databases are essential for both large and small businesses, allowing them to store and manage data effectively.

Types of Databases
There are two main types of databases:

• Relational Databases (SQL): Store data in structured tables with rows and columns, suitable for consistent data, like e-commerce transactions.
• Non-relational Databases (NoSQL): Store data in a non-tabular format, useful for data with varying formats, like social media content.

Tables, Rows, and Columns
Relational databases store data in tables. Each table has columns defining the data types and rows representing individual records. Data types include Strings, Integers, Floats, and Dates. For example, a table for books might have columns like “id,” “Name,” and “Published_date,” where each entry or “row” represents a book.

Primary and Foreign Keys

• Primary Key: Ensures uniqueness within a table, like a student ID.
• Foreign Key: Links one table to another, enabling relationships, like an “author_id” in a “Books” table connecting to an…