C.W.K.
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Quiz · 5 questions

📝 Queries

SELECT, joins, aggregation, windows, CTEs

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Quiz

01What does the RETURNING clause do in PostgreSQL?
02Why does NOT IN with a NULLable subquery return zero rows?
03What does COALESCE(a, b, c) return?
04Why is OFFSET-based pagination slow at scale?
05Which window function gives unique sequential numbers with no ties?
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