The Database Requirement That Foreign Keys Must Be Null or Have

question 62

Multiple Choice

The database requirement that foreign keys must be null or have a value corresponding to the value of a primary key in another table is formally called the

• A)entity integrity rule.
• B)referential integrity rule.
• C)unique primary key rule.
• D)foreign key rule.

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Definitions:

Long-Run Supply Curve

A graphical representation showing the quantities of a good a supplier is willing to produce and sell at different prices over a long period, without fixed inputs.

Constant Returns

A situation where increasing the amount of inputs in the production process proportionally increases the output, implying a linear relationship between inputs and outputs.

Marginal Cost Curve

A graphical representation showing how the cost of producing one more unit of a good changes as production increases.

Profit Maximization

A process or strategy employed by businesses to increase their net profits to the highest possible level.