DATE_FORMAT()

Format patterns control how timestamps appear in output. Each letter represents a specific component: US format with 12-hour clock and AM/PM. European format with 24-hour clock. Compact format for filenames and sorting - no separators, lexicographically sortable. Output for Reports Reports often need human-readable dates with full month names: '%M' gives the full month name. '%W' gives the full weekday name. These patterns make dates immediately readable without mental conversion. API and File Output ISO 8601 is the standard for cross-system data exchange. The Z suffix indicates UTC timezone. Mastering timezone conversions, truncation, and formatting prepares you for global applications. Practice these patterns to build robust date handling logic.

About This Interactive Section

This section is part of the Dates: Advanced 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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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.