Querying a Table

Step 1: Start with a question

Let’s imagine you’re exploring a table named employees. You don’t know what’s in it yet.

Prompt: Write a SQL query that displays all employees from the employees table.

Step 2: Run and observe

AI will probably return:

You should see something like:

Take a moment to visualize your data structure:

• Each row represents a single record, in this case, an employee.

• Each column represents a specific piece of information about that record.

When you write:

SELECT *

You’re telling SQL: Show me every column in the table.

Step 3: Narrow the focus

Seeing everything is messy. Let’s make our question sharper: Show me each employee’s first name and department.

Use the AI again.

Prompt: Write a SQL query that shows only the employee’s first name and department from the employees table.

AI might give you:

 Run it. You’ll now see a cleaner table with fewer columns and the same rows.

Step 4: Reflect and interpret

Let’s think together:

• SELECT: Which columns do I want?

• FROM: Which table has them?

• *: All columns (not always useful).

A good SQL query isn’t just syntax; it’s a clear question. Every line you write should match the question you’re asking.

Step 5: Your turn to tweak

Now you’ll make a small edit yourself. No AI this time, type directly in the SQL widget.

Challenge: Change the query so it shows first_name, last_name, and salary of all employees.

Did you get a new table with just those three columns?

Quick recap

Practice prompt ideas

Use the AI Prompt Widget to try your own:

1. Show me the names and salaries of employees.

2. Show only the employee id and department.

3. List all columns again using SELECT *.

Then tweak one of them yourself to add or remove a column.

Reflect before moving on

Ask yourself:

• How did my question in plain English become SQL?

• Why is narrowing columns helpful?

• What would I ask next to start learning about the types of data this table holds?