MySQL Setup and First Commands

Your first MySQL session

Once MySQL is installed, the first thing to learn is the basic flow: create a database, select it, create a table, add data, and view it. These five commands are the foundation of everything else. Every command ends with a semicolon ;.

Create a database

CREATE DATABASE school;

This makes a new, empty database called school. You can see all databases with SHOW DATABASES;. Names should be simple and have no spaces.

Select the database

USE school;

USE tells MySQL which database your next commands apply to. Forgetting this gives a "No database selected" error when you try to create a table.

Create a table

CREATE TABLE students (
    roll INT PRIMARY KEY,
    name VARCHAR(50),
    marks INT
);

This creates a students table with three columns. roll is the primary key (unique id), name holds up to 50 characters, and marks is a number.

Insert a row

INSERT INTO students (roll, name, marks)
VALUES (1, 'Aman', 88);

INSERT INTO adds a row. You list the columns, then the matching values. Text values go in single quotes; numbers do not.

View the data

SELECT * FROM students;

SELECT * shows all columns of all rows. This is how you check your data. Use SHOW TABLES; to list tables and DESCRIBE students; to see the columns.

Common mistakes

• Forgetting the semicolon. MySQL waits for more input without ;.
• Skipping USE. You get "No database selected".
• No quotes on text. String values need single quotes: 'Aman'.
• Spaces in names. Keep database and table names simple, no spaces.

Summary

• Create a database with CREATE DATABASE, then USE it.
• Create a table with columns and a primary key.
• Add rows with INSERT INTO ... VALUES.
• View data with SELECT * FROM table.
• End every command with a semicolon.

Next, explore more commands in MySQL CLI basics, or the command groups in DDL, DML and DQL.