Parameters and Arguments

Most useful functions need input data to work with. A function that calculates tax needs to know the price. A function that formats a name needs to know the name. A function that validates an email needs the email address to check. Parameters are variables that you define in the function signature to receive these input values. When you call the function, you provide arguments, which are the actual values that get assigned to those parameters. Multiple Parameters Functions frequently need multiple pieces of input data. You can define multiple parameters by separating them with commas in the function signature. When calling the function, you must provide arguments in the same order as the parameters appear in the definition. This is called positional matching because the position of each ar

About This Interactive Section

This section is part of the Functions: 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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