January 2008
Intermediate to advanced
384 pages
8h 1m
English
Content preview from Joe Celko's Thinking in Sets: Auxiliary, Temporal, and Virtual Tables in SQLBecome an O’Reilly member and get unlimited access to this title plus top books and audiobooks from O’Reilly and nearly 200 top publishers, thousands of courses curated by job role, 150+ live events each month,
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1.4. Tables as Relationships
A relationship is shown in a table by columns that reference one or more entity tables. Without the entities, the relationship has no meaning, but the relationship can have attributes of its own. For example, a show business contract might have an agent, a studio, and a movie star. The method of payment is an attribute of the contract itself, and not of any of the three parties.
These tables will always have FOREIGN KEY references to the entities in the relationship and DRI actions to enforce the business rules.
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