Ratio Scales (Ratio scales are what people think of when they think about a measurement)
- Ratio scales have an origin, an ordering, and a set of operations that can be expressed in arithmetic.
- They are called ratio scales because all measurements are expressed as multiples of fractions of a certain unit or interval.
- Examples: length, mass, and volume. (The unit is what is arbitrary; the weight of a bag of sand is still weight whether it is measured in kilograms or in pounds)
- Make sure that each table in your database has been reviewed for possible relationships with other tables.
- For tables with relationships to other tables, make sure that the relationship has been properly identified. This would include: A. The type of participation between the tables; B. The degree of participation between the tables.
- Make certain that each foreign key meets the following best practice suggestions: A. The name of the foreign key should match the name of the primary key it is related to (a data element has only one and only one name in a schema); B. The column specifications of the foreign key are identical to those of the primary key.
- This level of integrity is a vital aspect of database design and the following lists some of the more important terms associated with integrity: A. Column Specification (general elements, physical elements, and logical elements); B. Data Integrity (table-level, column-level, and referential integrity)
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