An introductory explanation of Structured Query Language (SQL), its purpose, and where it’s used.
SQL—short for Structured Query Language—is the universal language for working with data stored in relational databases. If you've ever used an app, visited a website, or opened a dashboard, chances are high that SQL was working behind the scenes.
In this beginner-friendly guide, you’ll learn what SQL is, what it's used for, and why it remains one of the most in-demand skills in tech.
Want to try it out for yourself? Use the Galaxy SQL Editor to run real queries with no setup.
SQL (pronounced "ess-cue-ell" or sometimes "sequel") is a declarative programming language used to manage and query data in relational databases.
With SQL, you can:
SELECT)INSERT)UPDATE)DELETE)CREATE, ALTER, DROP)SQL is the language that powers tools like PostgreSQL, MySQL, SQLite, SQL Server, and many modern cloud databases.
SQL was developed in the 1970s by IBM researchers as a way to interact with data using human-readable commands. It became the standard language for relational database management systems (RDBMS) and was later adopted by ANSI and ISO.
The key idea: users shouldn’t need to know how the data is stored—just how to describe what they want.
Here are some everyday tasks that SQL makes possible:
SELECT name, email FROM users WHERE is_verified = true;
Returns a list of verified users.
INSERT INTO users (name, email) VALUES ('Alice', 'alice@example.com');
UPDATE users SET is_active = false WHERE last_login < '2023-01-01';
DELETE FROM users WHERE email IS NULL;
Explore more data manipulation in our INSERT/UPDATE/DELETE guide.
When you run a SQL query, the database:
Learn more in How SQL Works and How Databases Store Data.
A relational database organizes data into tables made up of rows and columns. Tables can be related to each other using primary keys and foreign keys.
For example, a users table and an orders table can be joined by user_id:
SELECT users.name, orders.total
FROM users
JOIN orders ON users.id = orders.user_id;
Learn more in our JOINs guide.
Yes—SQL is a domain-specific language designed for querying and manipulating data. It’s not a general-purpose language like Python or JavaScript, but it’s incredibly powerful for data tasks.
SQL has been around for 50+ years—and it’s still everywhere:
Whether you're a software engineer, data analyst, or startup founder, knowing SQL gives you superpowers when working with data.
You can use SQL in many places:
SQL is the language that makes modern data work. It's readable, powerful, and flexible—and it's one of the easiest ways to get started with technical work, even if you're brand new to programming.
You don’t need to install anything to try it. Just visit the Galaxy SQL Editor, and write your first query in seconds.
Continue learning:
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