Pick and Shovel Construction Company
SITUATION:
Pick and Shovel Construction Company is a multi state building contractor specializing in medium-priced town homes. C. T. Scott, the owner, is in your office for the third time today to see how the new relational database project is coming along. Unfortunately, someone mentioned to C. T. that the delay had something to do with achieving normalization.
“Why is all this normalization stuff so important?” he asks. “The old system worked
OK most of the time, and now you are telling me that we need all these special rules.
Why is this necessary?”
1. How should you respond to C. T.? Write him a brief memo with your views.
Normalization has to be eliminated to eliminate redundant data (making sure that all data is stored in only one place), to enforce data consistency, to ensure data dependencies to be logical (meaning that data is stored in the correct table), and to isolate data (so that the changes made to a field or table does not affect others).
2. Assume that the Pick and Shovel’s main entities are its customers, employees, projects, and equipment. A customer can hire the company for more than one project, and employees sometimes work on more than one project at a time. Equipment, however, is assigned only to one project. Draw an ERD showing those entities.
3. Add cardinality notation to your ERD.
4. Create 3NF table designs.
(INF TABLE)
* we already satisfy the 1NF and 2NF table* (See picture above)
3NF Table
*Proj. Code and Equipment were eliminated because they are dependent on proj. Name and not on our primary which is the C.ID*
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