Your First Mission
Your first week as a Data Analyst
You just joined the analytics team at a retail company. On day two, the marketing lead pings you:
"We can only feature one customer segment in next month's campaign. Which one is quietly worth the most to us? Pull the numbers."
The answer is sitting in the company database. The tool that gets it out is SQL, and by the end of this 20-minute intro you will have found the insight yourself, in your browser, with zero setup.
Your mission: find which customer segment drives the most revenue. You will explore the data one small step at a time, and run real queries along the way.
A database is just tables
Companies store their data in a database: a set of tables, where a table is a spreadsheet with a strict shape: columns are the fields, rows are the records.
Here is the table you will explore, called orders. Each row is one order placed by a customer:
| id | customer | segment | country | channel | amount | status |
|---|---|---|---|---|---|---|
| 1 | Acme Corp | enterprise | USA | web | 4200 | completed |
| 2 | TechStart | smb | France | mobile | 890 | completed |
| 5 | CloudFirst | mid-market | USA | store | 1980 | cancelled |
See the segment column (enterprise, smb, consumer, mid-market) and the amount? Those two hold the answer to your mission. You just have to ask the data the right question.
Why this is the analyst's superpower
A spreadsheet breaks at 100k rows. SQL doesn't. It lets you slice, filter and summarise millions of rows in seconds, so you can go from raw data to a clear answer before the meeting starts. That is what the rest of this intro builds toward.
Next: let's open the data and look inside.