Consider a relation stored as a randomly ordered file for which the only index is an unclustered

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Consider a relation stored as a randomly ordered file for which the only index is an unclustered index on a field called sal. If you want to retrieve all records with sal > 20, is using the index always the best alternative? Explain.

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Database management systems

ISBN: 978-0072465631

3rd edition

Authors: Raghu Ramakrishan, Johannes Gehrke, Scott Selikoff

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Question Posted: Jun 27, 2016 06:04 AM

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Consider a relation stored as a randomly ordered file for which the only index is an unclustered

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No In this case the index is unclustered each qualifyin...View the full answer

Database management systems

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