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:

Toilet Trained

The process by which a young child learns to use the toilet for urination and defecation independently.

Sleep-walker

An individual who walks or performs other complex behaviors while in a state of sleep.

Somnambulism

Sleepwalking.

Sleep-walking

A sleep disorder characterized by walking or performing other complex behaviors while in a state of sleep.