Database Query Builder

Learn SQL by building queries from scratch to analyze employee and sales data

ProgressSection 1 of 6

Section 1: Introduction to Databases

📖

EXPLAIN: Understanding the Concept

🗄️ What is a Database?

A database is an organized collection of data stored in tables (like spreadsheets).

Why databases matter: Most business data lives in databases - customer info, sales records, inventory, etc.

SQL (Structured Query Language) is how you talk to databases to:

Retrieve data (SELECT)
Filter specific records (WHERE)
Sort results (ORDER BY)
Calculate totals (SUM, AVG, COUNT)

Think of SQL as Google search for your company's data!

👀

SHOW: Here's How It Works

👀 Sample Database Table

Here's an example "employees" table:

| id | name    | department | salary |
|----|---------|------------|--------|
| 1  | Alice   | Sales      | 75000  |
| 2  | Bob     | IT         | 85000  |
| 3  | Carol   | Sales      | 70000  |
| 4  | David   | IT         | 90000  |

Each row is a record (one employee), each column is a field (name, department, etc.).

✍️

PRACTICE: Now You Build It!

✍️ Your Turn: Understand the Structure

Review the employee table structure above.

Notice:

Each employee has an ID, name, department, and salary
Tables organize data in rows and columns
SQL lets us query this data efficiently

Code Editor

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💻 Output:

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