Chapter 7 | Database Design for Mere Mortals: A Hands-On Guide to Relational Database Design

1:	How do you identify and establish tables for the new database?
A1:	You identify and establish tables for the new database using the preliminary table list .
2:	Why do you use the preliminary field list to help you define tables for the database?
A2:	You use the preliminary field list to help you define tables for the database because the fields on the list may imply subjects that the database needs to track.
3:	What action do you take when an item on the list of subjects and a differently named item on the preliminary table list both represent the same subject?
A3:	When an item on the list of subjects and a differently named item on the preliminary table list both represent the same subject, you select the name that best represents the subject and use it as the sole identifier for that subject.
4:	What information does the final table list provide?
A4:	The final table list provides the name, type, and description of each table in the database.
5:	State three guidelines for creating table names .
A5:	These are the guidelines for creating table names: Create a unique, descriptive name that is meaningful to the entire organization. Create a name that accurately, clearly, and unambiguously identifies the subject of the table. Use the minimum number of words necessary to convey the subject of the table. Do not use words that convey physical characteristics. Do not use acronyms and abbreviations. Do not use proper names or other words that will unduly restrict the data that can be entered into the table. Do not use a name that implicitly or explicitly identifies more than one subject. Use the plural form of the name.
6:	State two guidelines for composing table descriptions.
A6:	These are the guidelines for composing table descriptions: Include a statement that accurately defines the table. Include a statement that explains why this table is important to the organization. Compose a description that is clear and succinct. Do not include implementation-specific information in your table description, such as how or where the table is used. Do not make the table description for one table dependent upon the table description for another table. Do not use examples in a table description.
7:	How do you assign fields to a table on the final table list ?
A7:	You assign fields to a table on the final table list by determining which fields best represent characteristics of the table's subject.
8:	State three guidelines for creating field names.
A8:	These are the guidelines for creating field names: Create a unique, descriptive name that is meaningful to the entire organization. Create a name that accurately, clearly, and unambiguously identifies the characteristic a field represents. Use the minimum number of words necessary to convey the meaning of the characteristic the field represents. Do not use acronyms, and use abbreviations judiciously. Do not use words that could confuse the meaning of the field name. Do not use names that implicitly or explicitly identify more than one characteristic. Use the singular form of the name.
9:	What two problems can poorly designed fields cause?
A9:	Poorly designed fields can cause problems with duplicate data and redundant data.
10:	What can you use to resolve field anomalies?
A10:	You can resolve field anomalies by ensuring that the field complies with the Elements of the Ideal Field.
11:	State three of the Elements of the Ideal Field.
A11:	These are the Elements of the Ideal Field : It represents a distinct characteristic of the subject of the table. It contains only a single value. It cannot be deconstructed into smaller components . It does not contain a calculated or concatenated value. It is unique within the entire database structure. It retains a majority of its characteristics when it appears in more than one table.
12:	Under what condition is redundant data acceptable?
A12:	Redundant data is acceptable when it is the result of resolving a multivalued field or an unnecessary duplicate field.
13:	In general terms, what three steps do you follow to resolve a multivalued field?
A13:	In general terms, these are the three steps you follow to resolve a multivalued field: Remove the field from the table and use it as the basis for a new table. Use a field (or set of fields) from the original table to relate the original table to the new table. Assign an appropriate name, type, and description to the new table and add it to the final table list.
14:	When is it necessary to use a duplicate field in a table?
A14:	The only instance in which it is necessary to use a duplicate field is when the field serves to establish a relationship between two tables.
15:	How can you refine table structures?
A15:	You can refine table structures by ensuring that each table complies with the Elements of the Ideal Table.
16:	State three of the Elements of the Ideal Table.
A16:	These are the Elements of the Ideal Table : It represents a single subject, which can be an object or event. It has a primary key. It does not contain multipart or multivalued fields. It does not contain calculated fields. It does not contain unnecessary duplicate fields. It contains only an absolute minimum amount of redundant data.
17:	What is a subset table?
A17:	A subset table is a table that represents a subordinate subject of a particular data table.

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