Seeing the Big Picture: SUM, AVG, and COUNT

Step 1: Start with a question

So far, you’ve been exploring individual rows—every employee, every record. Now let’s think bigger.

Instead of listing all employees, you want a single number, the total sum of all salaries.

Prompt: Write a SQL query that calculates the total of all salaries from the employees table.

Step 2: Run and observe

AI will likely produce:

Run it. You’ll see a single number.

Reflect:

• One row now represents the whole dataset.

• SUM() added up all ...