A derived attribute can be stored in a table or calculated on each occasion that it is required. An example of a derived attribute is your Grade Point Average which is calculated by adding together a score for each unit (e.g., HD=4, D=3, C=2, P=1, N=0) and dividing that by the number of units you have completed. Explain how the decision as to whether the Grade Point Average would be stored in a table or calculated would be made. You are administering a database in a large retail company that records sales at each of the company’s stores. Tuning the database to improve performance by adding indexes and optimising query execution is an important ongoing aspect of the physical database design. Which attributes in a database such as this (apart from the primary key) are likely to BENEFIT from being indexed? Which attributes would you generally avoid indexing, and why?

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A derived attribute can be stored in a table or calculated on each occasion that it is required. An example of a derived attribute is your Grade Point Average which is calculated by adding together a score for each unit (e.g., HD=4, D=3, C=2, P=1, N=0) and dividing that by the number of units you have completed. Explain how the decision as to whether the Grade Point Average would be stored in a table or calculated would be made.

A derived attribute can be stored in a table or calculated on each occasion that it is required. An example of a derived attribute is your Grade Point Average which is calculated by adding together a score for each unit (e.g., HD=4, D=3, C=2, P=1, N=0) and dividing that by the number of units you have completed. Explain how the decision as to whether the Grade Point Average would be stored in a table or calculated would be made.

Programming Logic & Design Comprehensive

9th Edition

ISBN:9781337669405

Author:FARRELL

Publisher:FARRELL

Chapter8: Advanced Data Handling Concepts

Section: Chapter Questions

Problem 17RQ

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