Data Interview Prep Guides
Deep dives into the patterns interviewers actually test, written and verified by a working data analyst. Each guide links straight to free practice questions you can solve in your browser.
Practice eight SQL window function interview questions with one realistic dataset, progressive hints, tested solutions, and exact output…
September 4, 2026 · Noam Shabtai
SQL GROUP BY vs Window Functions: Choose by Output GrainUnderstand when SQL GROUP BY should collapse rows and when a window function should preserve them, with practical patterns, mistakes, and…
August 31, 2026 · Noam Shabtai
ROW_NUMBER vs RANK vs DENSE_RANK: SQL Ranking Ties ExplainedChoose ROW_NUMBER, RANK, or DENSE_RANK correctly by seeing how SQL ranking ties, gaps, top-N rows, and score levels change the result.
August 31, 2026 · Noam Shabtai
SQL Window Functions Interview Questions: The 6 Patterns That Actually Come UpThe six window function patterns that cover almost every real data-analyst interview question, each with a runnable query and its unedited…
June 12, 2026 · Noam Shabtai
Why Practicing SQL Still Matters When AI Writes It for YouAI writes the SQL now, and your job is to review it. A working data analyst on why architecture intuition and code reading are the skills…
June 10, 2026 · Noam Shabtai