1.3. Tables as Entities

An entity is a physical or conceptual “thing” that has meaning in itself. A person, a sale, or a product would be an example. In a relational database, an entity is defined by its attributes, which are shown as values in columns in rows in a table.

To remind users that tables are sets of entities, I like to use collective or plural nouns that describe the function of the entities within the system for the names of tables. Thus “Employee” is a bad name because it is singular; “Employees” is a better name because it is plural; “Personnel” is best because it is collective noun and does not summon up a mental picture of individual persons, but of an abstraction (see SQL Programming Style, ISBN: 0-12088-797-5, for more details). ...

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