2.2 Lab - Hello World MySQL

Introduction

This lab introduces you to working with MySQL from the command line. You will learn how to connect to a MySQL server, create a database, define a table, insert data, and query it. This foundational "Hello World" exercise will prepare you for more complex SQL tasks.

Objectives

By the end of this lab, you will be able to:

1. Connect to a MySQL server using the command line.
2. Create a new database.
3. Define a simple table within the database.
4. Insert a record into the table.
5. Query the table to retrieve data.

Lab Steps

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Step 1: Open the Command Line and Log In to MySQL

1. Open your terminal or command prompt.

2. Log in to the MySQL server using the following command:

   mysql -u root -p
   

   • Replace root with your MySQL username if different.
   • Enter your MySQL password when prompted.

3. After a successful login, you will see the MySQL prompt:

   mysql>
   

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Step 2: Create a Database

1. At the MySQL prompt, create a new database named hello_world:

   CREATE DATABASE hello_world;
   

2. Use the newly created database:

   USE hello_world;
   

   • You should see the message Database changed.

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Step 3: Create a Table

1. Define a table named greetings with the following structure:

   • id (integer, primary key, auto-incremented)
   • message (text, stores a greeting message)

   Execute the following SQL statement:

   CREATE TABLE greetings (
       id INT AUTO_INCREMENT PRIMARY KEY,
       message TEXT NOT NULL
   );
   

2. Verify the table creation by describing its structure:

   DESCRIBE greetings;
   

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Step 4: Insert Data into the Table

1. Insert a "Hello, World!" message into the greetings table:

   INSERT INTO greetings (message) VALUES ('Hello, World!');
   

2. Confirm that the data has been added:

   SELECT * FROM greetings;
   

   • You should see output similar to this:

     +----+--------------+
     | id | message      |
     +----+--------------+
     |  1 | Hello, World!|
     +----+--------------+
     

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Step 5: Query the Data

1. Retrieve only the message column from the table:

   SELECT message FROM greetings;
   

2. Experiment by adding another greeting and querying the data again:

   INSERT INTO greetings (message) VALUES ('Welcome to MySQL!');
   SELECT * FROM greetings;
   

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Step 6: Exit MySQL

1. Exit the MySQL command line:

   EXIT;
   

2. Close your terminal or command prompt.

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Summary

In this lab, you learned how to:

• Connect to MySQL from the command line.
• Create and use a database.
• Define a table with basic structure.
• Insert and retrieve data from a table.

This "Hello World" lab serves as your first step into MySQL, providing hands-on experience with the essential commands needed for database interaction. In the next lab, we will build on these concepts by exploring how to filter and sort data using SQL queries.