Question

Which of the following describes referential integrity?

A. A Primary Key of a relational table must not contain a null value

B. One fact must not be in multiple places

C. The value for a foreign key attribute must either be null or match the one of the data value of that attribute in the table in which the attribute is a primary key

D. Referential Integrity is a principle that prevents the use of redundancy, avoids null values and creates a minimal database

E. Multiple facts must not be stored in a single cell

Which of the following is most likely a violation of the one-fact, one-place rule

A. Customer Id is used as a primary key of a sale table table

B. Cash Receipt id is posted as a foreign key in a sale table for a company that requires immediate cash payment in full for each sale

C. A Separate Table is created to represent an association between warehouses and inventory with multiplicities 1..* - 0..* and the attribute "quantity on hand" is assigned to the association table.

D. Customer id posted as a foreign key in a sale table

E. A separate table is created to represent an association between Purchase and Cash, Disbursement with multiplicities 0..1 - 0..1 and the attribute " Amount of Cash Disbursement Applied to a Purchase" is assigned to the association table

Answer 1

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1) C. The value for a foreign key attribute must either be null or match one of the data values in the table in which the attribute is a primary key

2) A. Customer ID is used as the primary key of a Sale table.