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“完全约束”是什么意思?它用于http://en.wikipedia.org/wiki/Multivalued_dependency
我不确定这是否真的是一个普遍使用的术语。唯一的定义似乎在同一页面上,与“嵌入式约束”(我无法在任何地方找到定义)形成对比:
完全约束:表达数据库中所有属性的约束。(与嵌入式约束相反。)
就文章中给出的示例(两个多值依赖项course -> book和每个.course -> lecturer book(course, book, lecturer)course -> lecturerlecturer
course -> book
course -> lecturer
book
(course, book, lecturer)
lecturer