Module
Module 3 of 6Lesson 1 of 3~18 min

Load the dataset and write your first SELECT queries

Writing your first SQL queries means getting a factual answer without filing a ticket with the data team. You set up a SQLite environment in minutes, explore how the tables are structured, then select, filter and sort rows. A solid footing for every product question that follows.

Take this lesson: your first course is freeSee the full syllabus

Lesson objective

By the end of this lesson, you will be able to load the Atelio dataset into SQLite (in the browser or locally), explore the structure of the tables and write SELECT queries that pick columns, filter with WHERE, sort with ORDER BY and limit with LIMIT.

Topics covered

  • SQL queries
  • SELECT
  • WHERE
  • ORDER BY
  • SQLite

Where it fits

First queries

How do I get a reliable number from a table myself, without being caught out by missing values and dates?

Lessons in this module

  1. Load the dataset and write your first SELECT queries (this lesson)
  2. Count, sum, group
  3. Missing values and dates, two traps that produce wrong numbers

What you will learn in the course

This lesson is part of the course Model your product’s data and query it with SQL

  • Read a data model (tables, primary and foreign keys, cardinalities, entity-relationship diagram) and connect it to the product's screens and rules.
  • Model the data of a feature (entities, attributes, relationships, keys, cardinalities) and get the model validated by the engineering team.
  • Compare a relational database and a document (NoSQL) database for a product need and justify the choice based on expected queries, consistency and change.
  • Write queries that filter, sort and aggregate (SELECT, WHERE, ORDER BY, GROUP BY, HAVING) while handling NULL values and dates correctly.
  • Combine several tables with INNER and LEFT joins, and check that the result neither loses nor duplicates any row.
  • Turn a product question into a verifiable query, using CTEs and simple window functions (ROW_NUMBER, LAG, SUM OVER).
  • Query data read-only while protecting personal data, and have an AI draft SQL while checking every query before using its result.

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