Usually,a Table in a Relational Database Must Have a Primary

question 61

True/False

Usually,a table in a relational database must have a primary key,and most relational DBMSs enforce this rule.

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Definitions:

Phenol

An aromatic compound consisting of a benzene ring bonded to a hydroxyl group (-OH).

Ethanol

A volatile, flammable, clear liquid also known as alcohol, used as a solvent, in the manufacture of various chemicals, and as an intoxicant.

Acetic Acid

A weak carboxylic acid with the formula CH3COOH, known for its sour taste and pungent smell, used in vinegar.

Carbonyl

A functional group consisting of a carbon atom double-bonded to an oxygen atom, central to various organic compounds including aldehydes and ketones.