Skip to Main Content
Data Analysis for Database Design, 3rd Edition
book

Data Analysis for Database Design, 3rd Edition

by David Howe
May 2001
Intermediate to advanced content levelIntermediate to advanced
336 pages
14h 36m
English
Butterworth-Heinemann
Content preview from Data Analysis for Database Design, 3rd Edition
A special case of a derivable attribute is where an attribute type is redundantly
duplicated, as in:
Employee (employeeNo, employeeName, projectNo, projectName)
Project (projectNo, projectName, projectStartDate)
Here, projectName is immediately available within either table.
Questions
1. An entity table is defined as:
Machine (machineNo, type, location, contractorAddress, contractType,
contractServiceDate, contractCharge)
Maintenance contracts apply to only 10 per cent of machines. Suggest how the table
could be flexed into two tables to reduce storage requirements. (1 min)
2. With reference to question 1, both the tables generated by flexing would have to ...
Become an O’Reilly member and get unlimited access to this title plus top books and audiobooks from O’Reilly and nearly 200 top publishers, thousands of courses curated by job role, 150+ live events each month,
and much more.
Start your free trial

You might also like

Data Quality Engineering in Financial Services

Data Quality Engineering in Financial Services

Brian Buzzelli

Publisher Resources

ISBN: 9780750650861