The Database Constraint That Says That Foreign Keys Must Be

question 29

Multiple Choice

The database constraint that says 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)rule of keys.
• D)referential entity rule.

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Definitions:

Equilibrium Price

The price at which the quantity of goods supplied is equal to the quantity of goods demanded in a market, leading to market stability.

Units Of Output

A quantifiable count of the products or goods produced by a company or an industry.

Average Fixed Cost

The fixed costs of production divided by the quantity of output produced, decreasing as more is produced.

Short Run

A time period in economics where at least one factor of production is fixed, limiting the ability of businesses to adjust to changing market conditions.