Comparison operators (<, >)
Numeric and date comparisons let you filter based on relative values rather than exact matches. These operators compare values to find things that are bigger, smaller, or within a range. They work with numbers and dates. Comparison operators: Example: Greater Than Working with Ranges Boundary conditions determine whether the exact threshold value is included or excluded from results. Inclusive vs Exclusive The difference matters when you hit the exact boundary number. Watch how the filter checks each row against the threshold. Stock values of 10 or less pass through (5, 10, 3, 8). The value 15 is filtered out because it exceeds the threshold. Notice that 10 itself is included because the operator is <= (less than or equal). Example: Less Than or Equal Use <= to find values at or below a th
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.
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