database interface of a library allows searching only for a single attribute (such as or Author.) in each query. Your friend decided to extend it's functionality and wrote an algorithm that allows searching for books that satisfy multiple predicates over single attributes in conjunction. He tells you the algorithm reuses the already implemented query functionality and works by intersecting the results (_book id's.) of queries over single attributes. Which of the following assumptions on your friend's algorithm are plausible? a) Its worst-case run-time necessarily increases exponentially with respect to the number of attributes in the query. b) Its worst-case run-time depends on the length of the longest result of the single-attribute queries. c) It might be implemented using an join. d) It might be implemented using sorting.

database interface of a library allows searching only for a single attribute (such as or Author.) in each query. Your friend decided to extend it's functionality and wrote an algorithm that allows searching for books that satisfy multiple predicates over single attributes in conjunction. He tells you the algorithm reuses the already implemented query functionality and works by intersecting the results (_book id's.) of queries over single attributes. Which of the following assumptions on your friend's algorithm are plausible? a) Its worst-case run-time necessarily increases exponentially with respect to the number of attributes in the query. b) Its worst-case run-time depends on the length of the longest result of the single-attribute queries. c) It might be implemented using an join. d) It might be implemented using sorting.

Database System Concepts

7th Edition

ISBN:9780078022159

Author:Abraham Silberschatz Professor, Henry F. Korth, S. Sudarshan

Publisher:Abraham Silberschatz Professor, Henry F. Korth, S. Sudarshan

Chapter1: Introduction

Section: Chapter Questions

Problem 1PE

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