Top SQL Commands to Know for Working with Databases

Structured Query Language (SQL) is used to talk to databases. Whether you're retrieving data, modifying it, or managing tables and users, it all comes down to knowing the right commands. This article walks you through the most important ones step by step.

Most-Used SQL Commands Explained

Here are some of the top SQL commands and how they’re used:

SELECT

SELECT * FROM users;

Retrieves all rows from the users table.

INSERT INTO

INSERT INTO users (name, age) VALUES ("Alex", 35);

Adds a new user named Alex.

UPDATE

UPDATE users SET age = 36 WHERE name = "Alex";

Changes Alex’s age to 36.

DELETE

DELETE FROM users WHERE age < 18;

Removes underage users.

CREATE DATABASE

CREATE DATABASE company;

Creates a new database called company.

JOIN

SELECT U.name, O.amount FROM users U JOIN orders O ON U.id = O.user_id;

Combines user and order data.

GROUP BY

SELECT age, COUNT(*) FROM users GROUP BY age;

Counts how many users are in each age group.

FAQ

Why is SQL still important?

SQL is used everywhere databases exist. It’s universal, reliable, and powerful.

Do all commands work in every database?

Mostly yes, though some syntax and behavior may differ slightly between systems like PostgreSQL, MySQL, or SQL Server.

What are good tools for working with SQL?

DbVisualizer is a great SQL client. It supports many DBMS platforms and makes writing and testing queries faster.

Can I combine commands?

Absolutely. You can SELECT with a JOIN, filter with WHERE, group with GROUP BY, and more, all in one query.

Conclusion

SQL may seem simple, but it powers nearly every major application today. By learning the commands in this guide, you’ll be able to read and write SQL confidently—No matter what DBMS you’re working with. These commands are the start of building more advanced queries and automations.

Check the Glossary of the SQL Commands You Need to Know article for more examples.