assn4 - Homework 4 1.264, Fall 2006 Data model for chemical...

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Homework 4 1.264, Fall 2006 Data model for chemical manufacturer Due: Thursday, October 12, 2004 A. Overview In this homework, you will build the data model that will support your Web application. The dataset is on the servers—see the MIT Server for details. Refer to problem set 2 and your requirements for data definitions and a description of the features that must be supported by your data. B. Data model The assignment is to build the data model for the chemical manufacturer. A recommended set of steps is given, although you are free to approach this as you wish. You must use Visual Paradigm; select the Entity Relationship Diagram. You are allowed to make the following assumptions: The international or UN number can be used as a primary or foreign key in all entities in which it appears. All chemical data has UN numbers. All UN numbers that are in the Isolation and Emergency Response data are in the Chemical Product data, so the Product entity can be the parent entity in these relationships. 1. Define the Chemical Product entity. Use international (UN) number as the primary key. This defines a unique chemical product at the manufacturer level. 2. Create a separate ChemicalName entity to hold the multiple names associated with each UN number. Don’t keep any chemical names in the Chemical Product entity. a. Build the relationship from ChemicalName to ChemicalProduct. In this entire homework, build the relationships right after building each new entity. Visual Paradigm will help create the foreign/primary key. 3. Create a domain (validation) entity to store the valid values of the chemical class data (1 through 9, with decimal subdivisions). Chemical class should be a foreign key in the Chemical Product entity you define, which Visual Paradigm will create automatically
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assn4 - Homework 4 1.264, Fall 2006 Data model for chemical...

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