Introducing data mindset sections. Learning SQL is one thing but understanding how you can approach any data problem related to SQL in a more structured and confident way is something to aspire for.

We will have these sections in the middle of the main modules to help you build a mindset to interpret data, and tables and make you better at understanding the data and writing SQL.

This part would look a bit heavy but trust us you would be building solid fundamentals about tables and their relationship with each other that would only help you to speed up learning the rest of the SQL course and show your magic with SQL.

One of the most important concepts while dealing with tables is Primary Key and Foreign Key.

Primary Key:

• Definition: A primary key is a specific column (or set of columns) in a table that uniquely identifies each row. No two rows can have the same primary key value.
• Purpose: They're essential for JOIN operations, helping to combine data from different tables accurately.
• Sample Example: In an electronic store database, the product_id in a products table would typically be the primary key because every product has a unique product_id. No two products should have same product_id .

Food for Thought:

Questions:

1. How does a social media platform identify you uniquely?
2. When you place an order online, how does the e-commerce platform ensure your order is unique?
3. How does a bank ensure each transaction is distinct?
4. How does the transportation department uniquely identify each vehicle?

Answers:

1. Through a unique user ID or username.