The database interface of a library allows searching only for a single attribute (such as Title 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.

The database interface of a library allows searching only for a single attribute (such as Title 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.

Principles of Information Systems (MindTap Course List)

12th Edition

ISBN:9781285867168

Author:Ralph Stair, George Reynolds

Publisher:Ralph Stair, George Reynolds

Chapter5: Database Systems And Applications

Section: Chapter Questions

Problem 4PSE: Using a graphics program, develop an entity-relationship diagram for a database application for an...

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