Loops with while

Concepts covered: pyWhileLoops

Basic while Syntax The loop checks the condition, executes the body if True, then checks again. When count reaches 5, the condition becomes False and the loop ends. Here is the execution model step by step: Comparing while and for Choose the right loop type based on your situation: When deciding which loop type to use, keep these practical rules in mind. They cover the most common scenarios you will encounter in real code. Common while Patterns Here are typical use cases for while loops: Avoiding Infinite Loops A while loop that never ends is called an infinite loop. This happens when the condition never becomes False. Always ensure something in the loop body moves toward ending the loop: Can you spot the bug? This while loop has a subtle error that would cause it to run forever. Remove th

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This section is part of the Loops: 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.

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