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Calculate Table Fields - Exercise
Objective:
Compose a list of calculated fields.
Exercise scoring
This exercise is worth a total of 20 points. You will receive up to five points for each correctly submitted calculation according to the instructions below.
Background and Overview
In the preceding lesson, you learned that the base tables stored in a database cannot have calculations built into their fields. Instead, user views and database applications are created to perform calculations on data. User views are stored queries that deliver specified data from base tables into virtual tables that allow calculations to be performed. The key, then, is to determine what calculations to include in user views so that data is transformed into useful information for an organizations decision-makers.
Downloads
This exercise requires you to download (if you have not already done so) the sample case study available from the following link:
ERD Case Study
.
Instructions
Carefully read the Stories on CD, Inc. case study and list four calculations that would transform the company's stored data into useful information for running the business. Do not be concerned with creating user views, just imagine; user views with the calculated fields you provide included in them.
Hints
Approach this exercise as though you were Ted or Lisa: what information would you, as an owner, consider useful in making business decisions? The best
database designers
are those who
think
like users and producers of data. If you can combine
business sense
with database design skills, you will always have opportunities come your way.
Submitting your exercise
Type or paste your answers into the text box below, then click
Submit
to submit them and view a results page.