IN and NOT IN for list matching

Concepts covered: sqlInList

List matching simplifies queries when you need to check against multiple possible values at once. If the column value matches ANY item in the list, the row is kept. Example The "food" row is the only one rejected because it does not appear in the list. Every other type matches at least one entry and passes through to the result. Why IN Is Powerful More Examples Problem: Show sales from three specific categories. Problem: Get data for four specific customer IDs. How does IN handle a longer list of values? Excluding with NOT IN Basic Syntax Basic Example This returns all orders except those that were cancelled, refunded, or failed. The database checks each row's status against the exclusion list and returns rows that don't match any of the values. Real-World Example This filters a sales repo

About This Interactive Section

This section is part of the Filtering: Beginner lesson on DataDriven, a free data engineering interview prep platform. Each section includes explanations, worked examples, and hands-on code challenges that execute in real time. SQL queries run against a live PostgreSQL database. Python runs in a sandboxed Docker container. Data modeling problems validate against interactive schema canvases. All content is framed around what data engineering interviewers actually test at companies like Meta, Google, Amazon, Netflix, Stripe, and Databricks.

How DataDriven Lessons Work

DataDriven combines four interview rounds (SQL, Python, Data Modeling, Pipeline Architecture) with adaptive difficulty and spaced repetition. Easy problems get harder as you improve. Weak concepts resurface until you master them. Your readiness score tracks progress across every topic interviewers test. Every lesson section ends with problems you solve by writing and running real code, not by picking multiple-choice answers.