Search⌘ K
Home
Courses
Learn SQL in the Age of AI

GROUP BY and HAVING

Learn how to summarize and interpret data.

We'll cover the following...

Step 1: Start with a question

In the last lesson, you asked: What is the total salary cost for the whole company?

Now, let’s ask something smarter: “What’s the total salary cost for each department?” That’s where GROUP BY comes in; it summarizes data by group, not as a single total.

Prompt: Write a SQL query that shows each department and its total salary cost from the employees table.

Powered by AI
5 Prompts Remaining
Prompt AI WidgetOur tool is designed to help you to understand concepts and ask any follow up questions. Ask a question to get started.

Step 2: Run and observe

AI will likely produce:

MySQL
SELECT department,
       SUM(salary) AS "Total Salary"
FROM employees
GROUP BY department;

 Run it. This is your first grouped summary: each row is now one group, not one employee.

Reflect:

    ...