SQL — Introduction
What is SQL?
SQL (Structured Query Language) is how you talk to databases. Almost every app you use — banking, shopping, social media — stores data in tables and asks for it with SQL.
A database table looks like a spreadsheet:
| id | name | city |
|---|---|---|
| 1 | Ada | London |
| 2 | Grace | New York |
SQL lets you ask questions like "show me everyone in London" or "add a new customer":
SELECT name FROM customers WHERE city = 'London';
INSERT INTO customers (name, city) VALUES ('Alan', 'Oxford');
Why SQL is worth learning
- It's declarative — you describe what you want, not how to fetch it
- It's everywhere: every backend developer uses it weekly
- The basics take an afternoon; the skills last a career
- It consistently ranks among the most-demanded job skills
Reading SQL out loud helps
SELECT name, city FROM users ORDER BY name;
Reads as: "select the name and city columns from the users table, ordered by name."
Once you internalize that pattern, most queries become guessable.
Note: SQL keywords aren't case-sensitive (
SELECT=select), but writing them UPPERCASE makes queries easier to scan.
Next lesson: your first SELECT statements.
Related Topics
Frequently Asked Questions about Introduction
What is Introduction in SQL?
Introduction is a fundamental concept in SQL. This lesson explains it step by step with clear examples, making it easy for beginners to understand.
How do I learn Introduction?
Start by reading the explanation above, then try the code examples. Practice by modifying the examples and experimenting with different values. Hands-on practice is the best way to learn Introduction.
Why is Introduction important in SQL?
Introduction is essential for SQL development. Understanding this concept will help you write better code and solve real-world problems more effectively.