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We opened the chapter with a discussion of the preliminary table list. This list constitutes the initial table structures for the new database. You learned how to develop this list using the preliminary field list, the list of subjects, and the mission objectives, all of which you compiled during the analysis phase of the database-design process.

Next we discussed the procedure for transforming the preliminary table list into a final table list, which contains the name, type, and description of each table in the database. You learned a set of guidelines for creating table names, and another set of guidelines for composing table descriptions. We then worked on creating table names that are unambiguous, descriptive, and meaningful and descriptions that explicitly define tables, as well as stating their importance to the organization. You also learned that enlisting the help of users and management is crucial to the process of developing well-defined table descriptions. Table descriptions must be suitable and easily understood by everyone in the organization.

We then discussed the process of associating fields with each table on the final table list. Here you learned how to build a structure for a given table using fields from the preliminary field list that best represent characteristics of the table's subject.

Refining fields was the next subject of discussion, and you learned a set of guidelines for creating field names that will help you ensure that they are clear, descriptive, and meaningful. You also learned about the Elements of the Ideal Field. Now you know that you can resolve anomalies in a field by determining whether it complies with these elements. We then discussed how to resolve multipart and multivalued fields. You learned that decomposing multipart fields yields new fields, whereas decomposing multivalued fields yields new tables.

The chapter closes with a discussion of refining table structures. You learned to identify the Elements of the Ideal Table, and you now know that you can ferret out a problem in table structure by determining whether a table complies with these elements. We then discussed unnecessary duplicate fields, and you now know that they appear in a table for two reasons: to supply reference information or to represent different occurrences of the same type of value. You then learned how to resolve duplicate fields to eliminate the problems they present.

The final discussion centered on the topic of subset tables. As you now know, a subset table represents a subordinate subject of a particular data table, and there is a distinct relationship between the subset table and the data table. You also know that you can explicitly create subset tables. You then learned that you may have unknowingly created subset tables earlier in the database-design process and that you need to look for subset tables you have not previously identified. When you identify a subset table, you refine it and add it to the final table list.


Part II: The Design Process