What does the subquery SELECT * inside an EXISTS clause project?

All columns from the subquery table.

Nothing; the SELECT list in EXISTS is ignored by the parser, as it only checks for row presence.

An error since SELECT * is slow.

medium #sql #postgresql #retail

QUESTION 01 OF 02

EXISTS vs IN

Quiz for lesson: EXISTS vs IN

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Why is EXISTS often faster than IN for large subquery datasets?

About this Quiz

This interactive assessment is designed to test your understanding of EXISTS vs IN. Whether you are a beginner looking to grasp the basics or an experienced professional aiming to refine your skills, quizzes are an excellent way to validate your knowledge and identify areas for improvement.

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Self-assess your current skill level.
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