Most Popular MySQL Commands Every Developer Should Know

Most Popular MySQL Commands Every Developer Should Know

Whether you’re just getting started or need a quick refresher, this guide covers the most essential MySQL commands used in day-to-day development. We’ll go through the basics — selecting, inserting, updating, and deleting data — and touch on creating databases and tables, as well as using joins.

1. SELECT – Fetch Data from a Table

This is the most used command. It retrieves data from one or more tables.


-- Get all rows and columns
SELECT * FROM users;

-- Get specific columns
SELECT id, name FROM users;

-- Filter with WHERE
SELECT * FROM users WHERE age > 30;

-- Order results
SELECT * FROM users ORDER BY created_at DESC;

-- Limit number of rows
SELECT * FROM users LIMIT 10;

2. INSERT – Add Data into a Table

Used to insert new records.

</p>
-- Insert a single row
INSERT INTO users (name, email, age) VALUES ('Alice', '[email protected]', 25);

-- Insert multiple rows
INSERT INTO users (name, email, age) VALUES
('Bob', '[email protected]', 30),
('Charlie', '[email protected]', 28);
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3. UPDATE – Modify Existing Records

Use this to update data in the table.

</p>
-- Update a user's email
UPDATE users SET email = '[email protected]' WHERE id = 1;

-- Increase age for all users older than 30
UPDATE users SET age = age + 1 WHERE age > 30;
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Always use WHERE to avoid updating the entire table!

4. DELETE – Remove Records

Deletes rows from a table.

</p>
-- Delete one user
DELETE FROM users WHERE id = 5;

-- Delete users under 18
DELETE FROM users WHERE age < 18;
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Like UPDATE, always use WHERE unless you intend to clear the table.

5. CREATE DATABASE – Make a New Database

</p>
CREATE DATABASE my_app_db;

-- Use the new database
USE my_app_db;
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6. CREATE TABLE – Define a New Table

</p>
<p data-start="1624" data-end="1650">CREATE TABLE users (
id INT AUTO_INCREMENT PRIMARY KEY,
name VARCHAR(100),
email VARCHAR(100) UNIQUE,
age INT,
created_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP
);</p>
<p data-start="1624" data-end="1650">

7. JOIN – Combine Rows from Multiple Tables

MySQL joins are key for relational data.

</p>
-- INNER JOIN: Only matching rows
SELECT orders.id, users.name
FROM orders
INNER JOIN users ON orders.user_id = users.id;

-- LEFT JOIN: All users, even if no order
SELECT users.name, orders.id
FROM users
LEFT JOIN orders ON users.id = orders.user_id;
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8. Bonus Commands

DROP – Delete Tables or Databases

</p>
-- Drop table
DROP TABLE users;

-- Drop database
DROP DATABASE my_app_db;
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ALTER – Modify Table Structure

</p>
-- Add a new column
ALTER TABLE users ADD COLUMN phone VARCHAR(20);

-- Rename a column
ALTER TABLE users RENAME COLUMN phone TO phone_number;

-- Delete a column
ALTER TABLE users DROP COLUMN age;
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Final Thoughts

These commands form the foundation of working with MySQL. As you build more complex apps, you’ll add things like indexing, stored procedures, and transactions — but these basics will take you 80% of the way.

If you’re a developer working with relational data, mastering these commands is a must.

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