Chapter 191 of 1963 min read
20.2 — Cumulative MCQ Bank
1. Which clause filters rows before grouping? A) B) ✅ C) D) 2. What does count? A) All rows B) Only unique, non NULL values ✅ C) Only NULL values D) Every column 3. A scalar subquery must return: A) Many rows B) Exactly…
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